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ELEMENTS OF CHEMISTRY
AND
DENTAL MATERIA MEDICA
BY
J. S. CASSIDY, D.D.S., M.D
Pkofessok of Chemistry and Materia Medica in Ohio College of
Dental Surgery
CINCINNATI
ROBERT CLARKE & CO
1893
COPYKIGHT, 1892,
By JAMES S. CASSIDY.
TO
ELIZA GUYTOE",
IN LOVINO APPRECIATION OF HER
CHRISTIAN FORTITUDE
AND
EXCEEDING PATIENCE
UNDER MANY TRYINO CIRCUMSTANCES,
Stbis ^ook is ^ffettionattlg ^nstribtb,
BY HER HUSBAND,
THE AUTHOR.
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C I I I
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PREFACE.
The labor involved in the preparation of the fol-
lowing pages, was assumed at the solicitation of
members of my classes; and also for the purpose
of testing the comparative value, to Dental Stu-
dents, of the two approved didactic methods of
teaching Chemistry and Materia Medica, i, e., by
Lectures and quiz, and by Recitation from approved
Text-books, in connection with suggestive experi-
ments.
The author lays no claim to originality of style,
or system, in presenting the subjects. The sub-
jects themselves, with few exceptions, are not elas-
tic, and admit of only slight variations from the
usual accepted phraseology.
Division of the volume into Three Parts was
made, with a view to the convenience of the three
graded classes, which now obtain, as required by
the Association of Dental Faculties.
The space given to the consideration of Chemi-
cal Philosophy, and Compound Radicals, as well as
that occupied by the few simple rules to be observed
in Prescription writing, Hud the approximate re-
vi Preface.
lations between the Metric, and Apothecaries sys-
tems, of weights and measures, will, not, I trust,
he regarded as superfluous; for dental students, as
well as those of medicine, are often sadly deficient
in a clear knowledge of those important accom-
plishments.
It may appear on first sight, that our Materia
Medica is too limited, and overshadowed by the
governing science of Chemistry; but the combina-
tion of these two branches of our curriculum, as
herein presented — which I believe is unique, and
to the advantage of the student — necessarily pre-
vents the complete exposition of at least those
drugs which are unessential in dental practice.
Description of the work performed by the class,
in our Chemical Laboratory, on Qualitative Analy-
sis, lias been omitted, inasmuch as a monograph on
that subject, will probably soon be forthcoming.
I have, of necessity, borrowed freely from the
authorities consulted, to all of whom it would be
impossible to give individual credit. Of these^
however, we must not forget the collective credit
due to various dental, medical, and scientific jour-
nals, and in especial manner to Fowne's, Atfield's,
Clark's, Appleton's, Mitchell's Dental, Roscoe's,
Crooke's, ai'Ui/:Barket!^;/<vhen:dstry ; Miller's Mi-
crobes, and Biddre^s, Polter^^, (jforgas.'. Dental, Bar-
Preface. vii
tholow's, Farquharson's, and Waring's Materia
Medica. To tliem, and many other friends, who
have assisted to render my task a labor of love, I
hereby extend my grateful acknowledgments.
J. S. CASSIDY,
1555 Madison Avenue, Covington, Ky., December 15, 1892.
Note. — By kindly referring to the Index, the reader will
observe a slight departure from the usual orthography of cer-
tain words. Thus will be found Chlori>2, lodni, Glycerin,
Cocam, Oxid, SuJfur, etc.
This innovation is in accord with the recent official report of
a Committee of the Chemical Section of the American Associ-
ation for the Ads^ancement of Science, and will probably be
generally adopted in the very near future. J, S. C.
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INORGANIC CHEMISTRY.
PAR^T FIRST.
CHAPTER I.
PHYSICS.
Matter and Force are involved in the consider-
ation of all natural phenomena.
Matter, substance, of which the physical uni-
verse is composed.
Force, modes of motion by which are manifested
heat, light, magnetism, and electricity; also motor,
or mechanical motion. All of these are inter-con-
vertible.
Specific gravity. Special kinds of matter, as
water, chloroform, gold, etc., differ from each other
in Aveight; or equal bulks of them are not affected
equally by the attraction of gravitation. They
differ therefore in specific gravity, or in the force
with which they fall to the earth.
The specific gravity of any substance is its loeight
compared with the weight of an equal bulk of the stand-
dard substance reckoned as unity.
In the case of all solids and liquids, distilled
water at a temperature of 4°C. (39°F.), is the stand-
(1)
2 ^ Inorganic Chemistiy.
ard of unity. A given temperature is necessary,
inasmuch as change, in this respect, either in-
creases or decreases the volume. The specific
gravity of any liquid is ascerfained by dividing its
weight, at the standard temperature, by the weight
of an equal bulk of water. The quotient will be
greater or less than unity, according as the weight
of the liquid in question, is greater or less than
that of the standard.
The specific gravity of a solid is obtained by the
same rule, viz., divide the weight of the solid by
the weight of the same bulk of the standard
(water). If the solid be heavier than water, it is
first weighed in air, then in water; it thus weighs
less in water than in air, and the loss in weight
expresses the weight of its own bulk of the liquid.
Its weight in air is divided by the amount it loses
by immersion in water; the quotient will be the
specific gravity of the solid.
When the solid body is soluble in water, then
some non-solvent liquid, the specific gravity of
which is known, is taken as a substitute.
In determining the specific gravity of a solid
lighter than water, various methods are employed.
A piece of metal, for instance, may be attached
to overcome the buoyancy of the light body, and
mathematical results thus obtained.
Physics. S
A sufficiently exact key to the general doctrine .
of the e([uilibrium of floating bodies is afl:brded by
the theorem of Archimedes.
A solid of less specific gravity than the liquid in
which it is placed will float. It displaces, at the
same time, a quantity of liquid exactly equal to its
own weight. Thus, a solid possessing one-half the
specific gravity of water, if placed in that liquid,
will sink one-half its bulk, the weight of the water
displaced, l)eing equal to the weight in air of the
floating body.
It is on this principle that instruments known
as hydrometers, urinometers, etc., are constructed,
by which a graduated stem, made of glass or
metal, floats in the liquid to be tested. If the
liquid be heavier than unity, the stem will be
raised accordingly, and vice versa, with liquids
lighter than water. The specific gravity of the
rKpiid will he indicated by the coincidence of
its surface with the figures on the graduated
scale.
The specific weights of gases are obtained by
dividing their weight by an equal volume of air.
In many cases hydrogen is taken as the standard
of unity for gases. The term dejisitij, when ap-
jdiod to a gas, implies that hydroiren is reckoned
as unity, and when the term specific gravity is em-
4 Inorganic Chemistry.
ployed with reference to the same, or some other
gas, it is understood that air is the standard of
unity.
PROPERTIES OF GASES.
G-ases or vapors, whether simple or compound,
are obviously affected by the attraction of gravita-
tion, in common with other forms of matter.
The atmosphere is the familiar prototype of
gases in general, and serves to exhibit certain phe-
nomena pertaining to all of them ; one of which
is the property of elasticity.
Air contained in a cylinder, in which works an
air-tight piston suffers condensation, if the piston
be pressed down ; whereas, if the pressure be less-
ened by raising the piston, the air will expand and
completely fill the enlarged space in the cylinder.
The volume of a given weight of gas depends
on the pressure : the relation being expressed by
the law of Mariotte, " The volume of a gas is in-
versely as the pressure ; the density and elastic
force are directly as the pressure and inversely as
the volume." Thus, 100 cubic inches of gas at the
ordinary pressure, will expand to 200 cubic inches,
if the pressure be reduced one-half, and shrink to
a volume of 50 cubic inches if the pressure be
doubled.
The atmosphere is the ocean of gaseous matter
surrounding the earth and held to the latter by the
Physics. 5
attraction of gravitation. Its weight, or density,
is therefore greater at the sea level, than at high
elevations; the density decreasing uniformly as
we ascend.
Instruments to indicate changes in the weight,
or pressure of the atmosphere at different eleva-
tions, or temporary changes in the pressure at a
given elevation, are called barometers.
The mercurial barometer is constructed by filling
completely, a glass tube about 35 inches long with
clean, dry mercury, and the open end of the tube
inverted in a reservoir of mercury. It will then
be seen that the mercurial column will descend in
the tube — leaving an empty space above — until it
reaches a position about 30 inches above the sur-
face of the mercury in the reservoir, at which point
it remains balanced by the pressure of the atmos-
phere. Now, if such a column of mercury, having
an area of 1 inch, be weighed, it will be found to
weigh between 14 and 15 lbs., proving that the
pressure of the atmosphere is nearly 15 lbs. on
every inch of the earth's surface.
The diffusive poicer of gases, depends on their rel-
ative densities; the rule being that " the diffusive
power of a gas is inversely as the square root of its
density." If a vessel be divided in two equal com-
partments by a thin, dry partition of plaster of
6 Inorganic Chemistry.
paris, and the two compartments filled with differ-
ent gases, incapable of acting chemically on each
other at ordinary temperatures, it will be found that
diffusion into each other will take place according
to the above rule.
If one compartment be filled with H, and the
other with 0, 4 cubic inches of H will pass
through the porous plaster of paris diaphragm, to
the oxygen side, while 1 cubic inch of 0 will pass
to the 11 side. The densities of these two gases
are as 1 to 16; their relative rates of dift'usion, are
inversely as the square roots of these numbers, or
as 4 to 1.
The inherent diffusive power of gases, whereby
the atmosphere absorbs them, prevents the accu-
mulation of poisonous vapors in confined localities,
their wide dissemination permitting the atmospheric
ozone to destroy them easily ; or they become so at-
tenuated in the air, as is the case with carbon-diox-
ide, ammonia, etc., that they exert no appreciable
influence on the health of the animal kingdom.
Certain gases, though comparatively dense, diffuse
most readily through wet membranes on account of
■ their great solubility ; as in the process of animal
respiration, the CO2, which is freely soluble in
water, escapes easily thus dissolved, through the
wet membranes of the lungs.
Effects of Heat.
CHAPTER II.
EFFECTS OF HEAT.
One of the most general eiFects produced on
matter, by increasing temperature, is expansion.
If a metallic bar be fitted accurately to a guage
when cold, and then slightly heated, it will be
found too long to enter the gauge. This is due to
the heat overcoming to that extent the attraction
of cohesion existing between the molecules of the
bar. If the heat be continued, the molecules may
be driven so far apart, that the metal will assume
the liquid state; and, finally, the metal may be
made to volatilize, or become gaseous, in which
condition, the molecules are widely separated. By
abstracting the heat, or allowing the mass to cool,
contraction takes place ; the space between the mol-
ecules is lessened, the metallic vapor changes again
to a liquid, and this back to the original solid con-
dition. The expansibility of most solids varies
with the increment of heat, zinc, lead, silver, cop-
per, gold, soft iron, tempered steel, untempered
steel, common white glass, platinum and flint glass,
expand in the order named.
8 Inorganic Chemistry.
It is seen that glass and platinum expand and
contract, nearly alike, and porcelain, whose nature
and expansive power approximates the former ma-
terial, permits fusion with platinum in the manu-
facture of artificial teeth, Logan crowns, etc., with-
out the danger of fracture, by excessive changes in
temperature.
Liquids not only differ in dilation by equal
amounts of heat, but they differ greatly in their
rate of expansion, by increasing temperature.
Mercury expands more uniformly between 0°C,
and 100°C, than other liquids, and for this reason
it is employed in the construction of thermome-
ters, instruments for measuring changes in tem-
perature. A glass tube closed at one end and
blown to a bulb, the other end left open and drawn
to a point, is partially filled \vith mercury. The
bulb is carefully heated, by which the air is driven
out, the tube being completely filled with the ex-
panded mercury ; the open end is then hermetically
sealed, and on cooling, the mercury contracts,
leaving an empty space above. The height of the
mercurial column is marked on the glass, at two
fixed points. These two points are found at the
boiling temperature of water, the barometric pres-
sure being noted, and at the freezing of water,
which is constant. Between these two marks, the
Effects of Heat. 9
tube is divided into an arbitrary number of degrees,
the scale continuing above and below each mark
respectively, to indicate temperatures above and
below the boiling and freezing points of water.
The Raumer scale is divided into 80 degrees; the
boiling point at 80°, the freezing point at 0°. Fah-
renheit's scale contains 180 degrees, but he placed
his 0°, 32 degrees below the freezing point; conse-
quently the boiling point is expressed by Fahren-
heit at 212°. According to the centegrade ther-
mometer, the freezing of water is* indicated by 0°,
and the boiling point by 100°. The graduation of
the latter instrument is considered the most ra-
tional. It is adopted by nearly all scientific bodies.
Fresh water when subjected to the freezing pro-
cess continues to contract in volume until it reaches
a temperature of 4°C, (-SO^F) — its point of maxi-
mum density. On further cooling it expands, until
the freezing temperature is reached, 0°C, (32°F.)
In the immediate act of solidifying, great enlarge-
ment takes place : ice is therefore formed on the
surface, being lighter than the liquid water beneath.
On melting, the reverse takes place; the volume
contracting until the temperature of 4°C is reached,
after which expansion proceeds with increasing
heat. In regard to the expansion of gases by heat,
the following statement will suffice :
10 Inorganic Chemistry.
I. All gases or vapors when remote from their
condensing points, expand nearly alike for equal
increments of heat.
II. The rate of expansion is uniform for all de-
grees of heat.
III. The rate of expansion is not altered by a
change in the state of compression or elastic force
of the gas itself.
IV. The actual amount of expansion is equal to
1 1
3QQQ of the volume of the gas at 0°C, for each
degree of that scale : 3,000 volumes of gas at 0°C
become 3,011 at 1°C, 3,022 volumes at 2°C, etc.
CONDUCTION OF HEAT.
The power of conducting heat varies greatly with
different bodies. If rods of the same size of differ-
ent solids have each one extremity heated equally,
the other extremities will become heated in the
ratio of the conducting power of the material.
The metals as a class are the best conductors of
heat (and electricity), silver being first. Rating
the conducting power for silver at 1,000 that of
Copper is 736
Gold is 532
Tin is 145
Iron is 119
Effects of Heat. 11
Lead is 85
Platinum is 84
Normal Moist Dentine is 15
Gold, and mercurial alloys of copper, and of silver
and tin — known as amalgams — are much better con-
ductors of heat than tooth structure, and to that
extent, at least, are objectionable materials for fill-
ing cavities in teeth. Tn sudden thermal changes
in the mouth, heat is conducted by them so rapidly
to or from the dental pulp, as to endanger the com-
fort and life of that organ.
Various other solids, mainly non-metallic, such
as glass, wood, vulcanite, gutta-percha, zinc ox-
ide cements, etc., are poor conductors. The last
two substances are frequently employed singly and
sometimes in union, as a protecting covering to
the pulp, before applying the metallic tilling.
Liquids and gases are classed as non-conductors
of heat; their increase in temperature is due to
convection, or the circulation of their particles
within the mass. Those particles nearest to the
source of artificial heat move away, giving place
to others of lower temperature, until all the par-
ticles acted upon are involved in the heating
process.
12 Inorganic Chemistry.
CHAPTEK III.
SPECIFIC HEAT.
Equal weights of different substances require
different amounts of beat to raise tbem a given
temperature. If 1 lb. of water at 40°C., and 1 lb.
of water at 10°C., be mixed, the mixture will pos-
sess the mean temperature of both, or 25°C. If 1
lb. of mercury at 40°C. be mixed with 1 lb. of mer-
cury at 10°C., the mixture will also possess a tem-
perature the mean of 40 and 10, or 25°C. IsTow, if
1 lb. of water, at 40°C., be mixed with 1 lb. of mer-
cury at 10°C., the temperature will not be 25°C., but
will be 39°C. The lb. of water at 40°C. loses but
1° in cooling from 40° to 39°, while it raises its own
weight of mercury 29°, from 10° to 39° ; the specific
heat, i. e., calorific capacity of water is, therefore,
29 times greater than mercury. The amount of
heat sufficient to raise a given weight of water
through a given range of temperature, referred
relatively to the amount of heat required to raise
equal weights of the different substances through
the same range of temperature, implies tlie spe-
cific heats — capacities for heat — of the various
Specific Heat. 13
substances. The specific beat of water is greater
tlian that of any other substance, excepting hy-
drogen. Taking water as unity — 1,000 — the ca-
pacity for heat, of an equal weight of hydrogen,
is expressed by 3.490, and gold by 0.324.
But if, instead of equal weights, quantities pro-
portional to the atomic weights of elements be
taken, there will be found a remarkable relation,
viz : " The atomic weights of the various elements
are inversely proportional to the specific heats, so
that the product of the specific heats into the
atomic weights is approximately a constant num-
ber. The same quantity of heat will produce a
given change of temperature in 7 grains of Li., 56
of Fe, 108 of Ag, 197 of Au, etc. These numbers
represent the atomic weights of the elements
named. In other words, the atoms of the several
elements have equal capacities for heat.
Latent Heat. — Whenever a solid melts or fuses
a certain amount of sensible heat disappears and
remains latent in the liquid.
One lb. of powdered ice or snow, at 0°C., placed
in 1 11). of water at 70C. will melt; the tempera-
ture, however, will not be 35°C. — the mean of 70°
and 0° — but will be reduced to 0°C. by the melting
of the ice, showing that 70°C. of heat have been
14 Inorganic Chemistry.
absorbed in the chanofe of state from solid to
liquid.
1 lb. of water at 70°C.
1 lb. of ice at 0°C.
This heat of fluidity is set free, when the water
again freezes; for, although the temperature of the
surrounding medium may be much lower than the
freezing point of water, so much latent heat is set
free by the change of state from liquid to solid, as
to keep the temperature up to 0°C.
This law of sensible heat becoming latent, when-
ever any solid becomes a liquid, also applies to
solids and liquids becoming gases, a certain amount
of heat disappears and remains latent in the gas;
and heat, to an exactly corresponding amount is
set free, when the gas again assumes the liquid
state.
A pound of water at lOO^C. mixed with a pound
of w^ater at 0°C., will occasion a temperature in the
mixture of 50°C., but a pound of steam at 100°C.,
if condensed to a liquid in water at 0°C., will,
by giving up its latent heat, confer a temper-
ature equal to its own of 100°C. on 5.4 pounds of
water at 0°C. It follows, that temperature is less-
ened by change of state from solid to liquid, and
from liquid to vapor. Fahrenheit mixed powdered
ice and salt : the mixture became liquid and re-
Specific Heat. 15
duced the temperature 32°F. (by his scale) below
the freezing point of water. He supposed this to
be the greatest absence of heat that could be arti-
ficially produced, and named the point zero (0°F.)
Ordinary chemical action always occasions a rise
in temperature ; but mere solutions generally lower
the temperature because of the amount of heat ab-
sorbed overcoming the heat developed by weak
chemical affinities. This is the principle of frigo-
rilic mixtures, such as powered calcium chloride
and snow; ammonium nitrate and water, etc.
The great reduction of temperature occasioned
by the rapid evaporation of highly volatile liquids,
such as ethyl chloride, ethyl oxide, etc., is due to
the heat absorbed and which remains latent in the
escaping vapor. In minor surgical operations,
some of these highly volatile liquids are applied
to the part, in the form of a spray, to obtund
sensibility.
Water evaporates at all temperatures, and, as
with other liquids, its evaporation is increased by
increase of heat. 'When the boiling point is
reached there is visible formation in the body of
the liquid of bubbles of gas, which ascend to the
surface and escape into the atmosphere as vapor,
carrying the latent heat with them, thus prevent-
ing the liquid from assuming a higher tempera-
16
Inorganic Chemistry.
tare. Water (or otlier liquid) boils, when the
elasticity of its vapor is able to overcome the pres-
sure upon it.
At the sea level water boils at 100°G., (212°F.),
but, at higher elevations, as on mountain tops, ebul-
lition takes place at a lower temperature, because
of the lessened pressure, or weight of the atmos-
phere. If water be made to boil in a partially
filled flask, the vessel then tightly corked and re-
moved from the source of heat, the boiling of the
water will soon cease by the pressure of its own
inclosed vapor. By applying to the surface of the
vessel a wet sponge, which condenses the vapor
and thus diminishes the pressure, ebullition again
takes place; and this repeatedly, until the water in
the flask is reduced to a common temperature.
Distillation, 17
CHAPTER IV.
DISTILLATION.
The object of distillation is either to separate
different substances which rise in vapor, at differ-
ent temperatures, from a composite liquid, or to
part volatile liquids from substances that do not
volatilize. When the process applies to solid
bodies passing directly to the gaseous state and
back again to the solid form, it is called sublimation.
Liquids evaporate at temperatures below the boil-
ing points, and the vapors thus escaping, as in the
case of water from the ocean and from the general
surface of the earth, are virtually distilled.
Vapor of water exists in the atmosphere at all
times and in all situations. If the aqueous vapor
he in condition of greatest possible density for the
temperature, or as is often but incorrectly ex-
pressed, the air be saturated with vapor of water,
the slightest reduction of temperature will cause
the deposition of a portion in the liquid form. If,
however, the vapor of water be below the point of
maximum density, that is, in an expanded condi:
tion, which is generally the case, a considerable
18 Inorganic Chemistry.
fall of temperature may occur before the dew. point,
or liquefaction commences. The resemblance be-
tween vapors, and what are ordinarily known as
gases suggested means by which all of the latter
class have been converted into liquids, by the influ-
ence of cold combined with pressure. Thus, chlo-
rine gas at a pressure of 4 atmospheres and a tem-
perature of 15.5°C., and nitrous oxide gas at a
pressure of 50 atmospheres and a temperature of
7.2°C., are condensed to the liquid state.
Nature of Heat. — Although the sources of heat
are numerous, such as the sun itself, the interior
of the earth, mechanical motion (the latter includ-
ing percussion, friction and condensation), electric
excitation and chemical action, a rise in tempera-
ture is caused in all cases by increased motions in-
duced in the particles of matter involved in its
development. It is probable that absolute zero or
perfect absence of molecular motion, does not ex-
ist. That matter changing from the gaseous to
the liquid, and on to the solid state, is owing to a
lessening in the molecular and atomic motion, con-
sequent on the withdrawal of a corresponding
equivalent of heat, and vice versa.
Light.— Rays of light, the effect of undulating
motion, projected from a luminous body, either ce-
lestial or terrestrial, while passing through homo-
Distillation.
19
geneous diaphanous media, travel in straight lines,
and with great velocity. If, however, the media
through which the light passes, should vary in
density, the ray of light will be changed in direc-
iion, will he bent from a continuous straight line ;
in short, refracted. The rale of simple refractio.n
of light is stated thus: lohen a ray of light loasses
from a rare through a denser medium, it is bent toward,
a line draivn perpendicular to the surface of the lat-
ter, and when passing from a dense to a rarer me-
dium it is bent from the perpendicular line, and
takes a direction parallel with a continuation of its
former course, provided the medium be the same
before and after refraction.
f
I
/A
//
//
/ /
/ /
B/ /
/C
Tf the incident ray of light, /, fall upon the plate
ghiss, A, at the angle shown, then instead of pass-
ing straight through tlu; glass to J3, it will be bent
toward the perpendicular line P to C, and on
20
Inorganic Chemistry.
emerging again into the air at C, it will be bent
from the perpendicular line, assuming a direction
parallel to its former course. It is upon this prin-
ciple that prisms and lenses depend. Convex sur-
faces converging the refracted rays, and concave
separating them more widely. In case the refract-
ing substances should be prismatic in form instead
of possessing parallel sides like plate glass, the ray
of light will be refracted as described, and also de-
composed into colors of different refrangibility.
(See spectrum analysis.)
If a ray of sunlight A be admitted into a dark
room and allowed to pass through a glass prism
at jB, the light is refracted; and if thrown on a
white screen (7, it will be seen to consist of several
colors, which form what is known as the solar
spectrum, and also as the primary colors. These
colors and their various shades are dependent on
I
Dislillation. 21
mathematical perception. The red color is dis-
tingiiished as such, because the vibrations of light,
producing it are received by the retina of the eye,
at the rate, in round numbers, of about 450 mil-
lion million times a second, and the violet at about
785 million million times a second. The interme-
diate colors and the infinite number of tints ac-
companying them are due to the variations in the
number of vibrations received by the normal hu-
man retina. Hence, color-blindness is owing to
the inability of the retina to receive a given num-
ber of vibrations within a given time. The solar
spectrum is often divided into three different parts ;
the most refrangible colors are known as the blue
rays, the richest in chemical influence; the least re-
frangible, or red, the heat rays, and the intermedi-
ate colors, the light rays. An invisible ray, more
refrangible than the violet, is richer in actinic
power than the latter, and a ray, also invisible, less
refrangible than any, possesses greater heating
power than the red.
Reflection of Light. — When a ray of light falls
upon surfaces, it is either absorbed and thus it
more or less disappears; or, it suffers reflection and
thus assumes a new direction. The law of the re-
flection of light is simply stated.
22
Inorganic Chemistry.
When a ray of light, J, falls upon a polished
surface, A, at a certain angle, it is reflected in the
direction of R, which makes an angle with the per-
pendicular line, P, equal to the angle of incidence.
In other words, the angles of incidence and reflec-
tion are equal.
R P I
Almost all things upon the general surface of
the earth, incline toward each other at promiscu-
ous angles, and so reflect the liglit diffused. It is
by means of this diffused reflected ligiit that we
are enabled to perceive objects distinctly. The
color of an object is due to its ability to reflect the
special rays or combination of them, by which it
is distinguished. A white object reflects all the
rays of light that fall upon it, while black absorbs
all, and reflects none.
Radiant Heat. — A few salient features of ra-
diant heat may be properly considered as an ac-
companiment to our studies of the nature of light.
When a hot body has its source of heat with-
drawn, it begins to cool immediately. It loses
heat in three ways.
Distillation. 28
1st. By conduction ; by means of the support
upon which it rests.
2nd. By convection ; the particles of air sur-
rounding the heated body, move away, carrying
their modicum of heat with them, and giving place
to other, colder, particles of air, which also become
heated and move away, and so on, all in accordance
with the law of hydrostatics.
3rd. By radiation ; a portion of heat escapes by
vibration in all directions from the heated body.
It meets with no interference from the air, and suf-
fers absorption and reflection, by surrounding bod-
ies, like rays of light.
In fixct, radiant heat resembles light in many re-
spects ; it travels with great velocity ; it is reflected
from surfaces ; it enters and traverses certain
media, undergoing at the same time refraction, ab-
sorption, and polarization, obeying in these re-
spects the same laws which regulate the corres-
ponding phenomena of light. Polished concave
surfaces will therefore reflect and concentrate the
heat rays to a focus, while convex surfaces will
cause them to diverge. Smooth, bright surfaces
reflect nearly all the heat that falls upon them, and
thus reniain cool; dark, rough surfaces, on the
contrary, soon become heated, by absorbing the ra-
diant heat, and reflecting scarcely any. Good re-
24 Inorganic Chemistry.
flectors are poor absorbers of heat, and vice versa.
The power of absorbing and of radiating heat, is
in direct proportion. The surface \^ihich absorbs
heat most perfectly, will when heated, also radiate
most perfectly. If two vessels of equal size and
material, one having a polished w^hite surface, the
other a dark, rough surface, be filled with hot
water, the rate of cooling by radiation will be un-
equal ; the water in the latter vessel will lose its
heat more rapidly than that in the one wdth the
polished surface. Hence, the dental pulp when
protected by a highly polished filling is not so
much affected by thermal changes, as it would be in
case the surface of the filling is roughly finished.
On this principle also, investments of artificial teeth
should be smoothly finished in order to prevent un-
due radiation of heat from the surface during the
process of soldering. At the same time, much heat
will be economized, if the blow-pipe flame be
thrown in such direction as to compel the reflected
heat to strike only some part of the investment.
Constitution of Matter. 26
CHAPTER Y.
CONSTITUTION OP MATTEK.
All kinds of matter may be divided into single or
elementary and compound forms. A compound con-
sists of two or more elements united together in
certain proportions. An acquaintance therefore
with the names of the several elements symbolized
by certain letters, and their atomic weights, or pro-
portions in which they unite to form compounds, is
necessary^ to the beginning of chemical studies.
The following table is presented for this purpose :
CONSTITUTION OF MATTER.
NAME. SYMBOL. - ATOMIC WEIGHT.
Aluminum Al 27
Arsenic .*.... As 75
Antimony Sb. (Stibium) 120
Boron B 11
Bromine Br 80
Barium Ba 137
Bismuth Bi 208
Carbon C 12
Chlorine CI 35-5
Calcium Ca 40
3
26 Inorganic Chemistry.
NAME. SYMBOL. ATOMIC WEIGHT.
Chromium Cr 52
Cobalt Co 59
Copper Cu. (Cuprum) 63-3
Colurabium Cb 94
Cadmium Cd 112
Caesium Cs 133
Cerium , Ce 141
Didymium Di 142-3
Decipium Dp
Erbium Er 166
Flourine F 19
Glucinum Gl 9
Gallium Ga 69
Gold Au. (Aurum) 196-5
Hydrogen H. = 1
Iron Fe. (Ferrum) 56
Indium In 113-6
Iodine 1 127
Iridium Ir 193
Lithi u m Li 7
Lanthanum La 138-2
Lead Pb. (Plumbum) 207
Magnesium Mg 24
Manganese Mn 55
Molybdenum Mo 96
Mercury Hg. (Hydrargyrum).. 200
Nitrogen N 14
Constitution of Matter. 27
NAME. SYMBOL. ATOMIC WEIGHT.
Nickel Ni 58
Oxygen O 16
Osmium Os 198
Phosphorus P 31
Potassium K. (Kalium) 39
Platinum Pt 195
Kubidium Rb 85-5
Ruthenium. Ru 104
Rhodium Rh 104
Sodium Na. (Natrium) 23
Silicon Si 28
Sulphur S 32
Scandium Sc 44
Selenium Se 79
Strontium Sr 87-5
Silver Ag. (Argeutum) 108
Titanium Ti 48
Tin Sn. (Stannum) 118
Tellurium Te 126
Terbium Tb
Tantalum Ta 182-6
Tungsten W. (Wolfram) 184
Thulium Tm
Thallium Tl 204
Thorium Th 232
Uranium U 239
Vanadium V 51-5
28 Inorganic Chemistry,
NAME. SYMBOL. ATOMIC WEIGHT.
Yttrium Yt 89
Ytterbium Yb 173
Zinc Zn 65
Zirconium Zr 90
For convenience of description, matter is divided
into three physical conditions ; namely, Solids, Li-
quids and Gases.
Gold and marble are examples of solids ; ordinary
water and the oils, of liquids; and the atmosphere
and nitrous oxide, of gases.
Each of these physical conditions is sub-divided
into masses y molecules and atoms.
A mass of matter is any quantity of matter ap-
preciable to the senses. A molecule is the smallest
particle of matter that can exist without losing
its identity. An atom is the still smaller particle
of matter obtained by division of a molecule. The
earth and a grain of sand are equally masses of
matter. The molecules of marble, consisting of
the metal calcium, and the non-metal carbon, and
the gas oxygen ; and the molecule of nitrous oxide,
composed of the two gasses, nitrogen and oxygen,
may be split up by chemical means into their con-
stituent atoms. From the molecule of marble the
individual atoms of calcium, carbon, and oxygen;
Constitution of Matter. 29
and from the molecule of nitrous oxide, nitrogen
and oxygen can be obtained.
The atoms of calcium, carbon, and oxygen, in
marble ; and of nitrogen, and oxygen, in nitrous
oxide, can not be further separated into simpler
forms. An atom itself is indivisible.
Chemical action involves the play of selective
affinities at given temperatures, between the con-
stituent atoms only, of the acting substances.
The force of attraction exerted on the above three
divisions of matter is threefold.
The attraction of gravitation between masses of
matter. The earth and other planets are held to
the sun, and the grain of sand to the earth, by
the attraction of gravitation. The attraction be-
tween homogeneous molecules, as those of marble,
gold, etc., is called cohesion, while that which holds
the atoms together to form the molecule is called
chemism, chemical attraction or chemical affinity.
The latter form of attraction is considered as
closely allied to the electric condition. As a class,
the atoms of the non-metallic elements, as oxygen,
sulphur, iodine, etc., are electro-negative, those of
the metallic elements, like silver, calcium and po-
tassium, are electro-positive. These two classes
are strongly attractive toward each other, while
the atoms of those elements intermediate between
30 Inorganic Chemistry.
the non-metallic and metallic elements, such as
arsenic, antimony, etc., will combine readily with
the atoms of either the negative or positive kind.
A molecule may he defined as consisting of a
definite number of atoms. A simple molecule
being made up of atoms of the same kind, as, for
example, a molecule of hydrogen, H-H; or of
oxygen, 0=0 ; or of ozone, ^^ A compound
molecule contains two or more atoms of different
kinds, as water H,0, or marble CaCO,. These
facts are ascertained by analysis and synthesis.
Analysis, which separates the constituent ele-
ments in compounds, and synthesis, which recom-
bines the elements to form compounds. From a
mass oi simple molecules only simple matter comes,
but from a mass of compound molecules, simple
matter is obtained.
From a mass of gold nothing but gold can be
obtained. Gold is, therefore, a simple form of
matter, or is an element. Water H,0, on the
contrary, is a compound, because by analysis it
gives np two diflierent substances, hydrogen and
oxygen ; but all efforts to divide either hydrogen or
oxygen into simpler forms fail ; they still remain
hydrogen and oxygen. They are, therefore, each
elementary.
Notation and Nomenclature. 31
CHAPTER YL
CHEMICAL NOTATION AND NOMENCLATUEE.
The letters, symbols — H, 0, or IN", etc., in the
table, on p. 26, 27, not only indicate the presence
of hydrogen, oxygen, nitrogen, etc., respectively,
but also certain quantities by weight of each, pro-
portional to their atomic weight.
Thus, the letter H symbolizes hydrogen, and at
the same time indicates 1 part by weight of hy-
drogen. Hydrogen being the lightest substance
known, the weight of its atom is taken as unity.
The letter 0, one atom, or 16 parts by weight of
oxygen. The letter N, one atom, or 14 parts by
weight of nitrogen, etc.
Combination between elements to form com-
pound molecules — which latter suggest a propor-
tional weight of a mass of the given compound —
is represented by placing the symbols in immediate
juxtaposition. Thus, HCl is a compound-mole-
cule— consisting of one atom, or 1 part by weight
of hydrogen, united to one atom, or 35 — 5 parts
by weight of chlorine. When there are more than
one atom of a certain element forming the mole-
32 Inorganic Chemistry.
cule, the appropriate figure is placed to the right
and a little below the symbol. The molecule of
water contains two atoms of hydrogen and one of
oxygen ; the formula for water is, therefore, II2O.
The formula of peroxide of hydrogen, which con-
tains two atoms of hydrogen and two atoms of
oxygen is written H2O2. When it is necessary to
multiply the molecule itself, the figure is placed to
the left, and on a line with the first symbol. The
formula 2H2O, means two molecules of water.
Sometimes when the molecule is somewhat com-
plicated, it is inclosed in brackets, and if multi-
plied, the figure is placed either to the left and on
a line, or to the right and a little below. Thus,
3(ISrH4Cl) or (NH4C1)3 represents three molecules
of a certain compound, each molecule containing
4 atoms of hydrogen, 1 atom of nitrogen, and 1
atom of chlorine. These few examples will suffice
for similar explanation of all other formulae.
In chemical changes every atom of each element
involved, must be accounted for. This is done by
placing the formulae of the reacting bodies first,
with a plus mark between them, followed by a sign
of equality and then the formulae of the bodies
produced by the change, with a plus mark be-
tween them. All of which constitutes a chemical
equation :
Notation and Nomenclature. 33
2IIC1 + Na2C03 = 2:N'aCl + ll^O + CO2
Hydroj^en Sodium Sodium Hydrogeu Carbon
Chloride. Carbonate. • Chloride. Monoxide. Dioxide.
The above equation is also an illustration of
wliat is termed double decomposition and recom-
position. Two molecules of hydrogen chloride, and
one molecule of sodium carbonate react upon each
other by means of the mutual affinities between
their atoms. The 2 atoms of hydrogen take one
atom from the 3 atoms of oxygen, forming a mole-
cule of water, (H2O.) The 2 atoms of chlorine set
free, unite with the 2 atoms of Xa forming 2 mole-
cules of common salt, (2 NaCl,) and the remaining
group, CO2 escapes as a molecule of carbonic acid
gas. Heat alone is oftentimes a most important
factor in causing chemical decomposition and re-
composition. If a salt known as ammonium ni-
trate be placed in a flask and heated sufficiently,
an interchange of the atoms of the constituent ele-
ments will take place, according to the following
equation :
NII4XO3 + Heat = 2H2O + :N'20
Ammonium Hydrogen Nitrous
Nitrate. Monoxide. Oxide.
It will be noticed by referring to the compounds
in the preceding equations, that their names sug-
gest their composition. When a compound mole-
cule is composed of only two elements its chemical
name always ends in ide^ as, hydrogen chloridCy
84 Inorganic Chemistry.
meaning, evidently, a combination of H and CI,
(IICl ;) hydrogen monoxide, of H and 0, (HgO;)
sodium c\\\oYide, of ^a and CI, (NaCl ;) Yiiirous
oxide, of ]^ and 0, (Ng^O The most highly elec-
tro-positive element in the formulae (a question to
be studied later), is generally placed first, a rule,
however, sometimes departed from, in order to
better explain the relations between the elements
in the group. In ammonium nitrate, the H, al-
though electro-positive, follows negative ^, thus,
NH4NO3, because we can better realize the relation
that really exists between the two radicals NH^
and isTOg, which form the molecule in question.
By referring to the few preceding formulae we
preceive the rule is observed, H is electro-positive
to CI ; Na to C and 0 ; ISTa to CI ; H to 0 ; and
C to 0.
In naming the compounds of inorganic chemis-
try, we shall employ the full name of the positive
element, preferring the noun to the adjective, as
more euphonious. Where the compound is made
up of elements which unite with each other in only
one proportion, that is, form but one compound, the
final syllables in the names of the electro-negative
elements are changed into ide. H and CI unite with
each other only in this proportion, H^Cl^^"^;
hence the name of such compound is hydrogen chlo-
Notation and Nomenclature. 35
ride. K and I form but one compound, KI, its
name is evidently potassium, iodide, etc. When two
elements unite with each other in iiiore than one
proportion, the distinctions are made by employ-
ing the Greek numerals, mon, di, iri, etc., to indi-
cate the number of atoms or radicles in the mole-
cule. H and 0 form two compounds, H2O and
II2O2 ; the first formula ma}' be called hydrogen
monoxide, the second hydrogen dioxide, signifying
one atom of oxygen and two atoms of oxygen re-
spectively. The binary compounds of IS' and O
furnish perhaps the best . example of these disr
tinctions;
N^O N2O2 N2O3 N^O, N2O5
Nitrogen Nitrogen Nitrogen Nitrogen Nitrogen
Monoxide. Dioxide. Trioxide. Tetroxide. Pentoxide.
The name alone, therefore, indicates the number of
O atoms in each molecule ; and they are all equally
(imitrogen oxides.
There are also different terminations in the
name of the positive element, to indicate the least
or greatest relative proportion of the negative ele-
ment in the series. In these nitrogen oxides, for
instance, the lowest or mon (one) oxide is most fre-
quently called wiivous oxide, and the highest, or
pent (five) oxide is known as wiiric oxide. The
prefix hyper (reduced sometimes to per) meaning
above, is found coiivea(eiil':tc/^pivly to the name of
• • •
• • •
• • •
3^ Inorganic Cheynistry,
a compound containing more of tlie negative ele-
ment than exists in a previously named compound
of the same elements. Thus nitrogen dioxide
might be named as hypermtrous oxide. The prefix
hjpoy meaning under, might, on tlie same principle,
be applied to nitrogen tetroxide, and the latter
named hypomtric oxide. These rules apply to any
series of compounds made up of the same two
elements.
etc '•t *- c C { c c
Notation and Nomenclature. 37
CHAPTER VII.
NOMENCLATURE.
The names of compounds more complicated in
the number of their elements than those men-
tioned in the preceding chapter, are, in inorganic
chemistry, derived mainly, from their composition.
Let it be understood that all acids contain H.
Nitric acid, as its name implies, contains IST. If
there be at least three elements in the molecules of
acids, a fact which usually obtains, we are safe in
assuming that 0 is the other element, unless the
name of the acid is otherwise distinguished. We
have, therefore, in the above acid, H and IST and O.
It remains only to correctly formulate the number
of atoms of each, to the molecule, and we accept
the proof of analysis and the process known as
equivalent substitution for this fact. The formula
of nitnc acid is thus ascertained to be HNO3.
Then, there is another oxy-acid of nitrogen ; it
is named mtvoiis acid — IINO2 — because it contains
less negative 0 than nitric acid.
The names of the other acids are derived in the
same way. Sulph,unV.P;Cid, is formulated II2SO4;
sulphuroi^s acid, :|J.jS0;]V. /^^'^.If^^^v acid, HCIO3 ;
38 Inorganic Chemistry.
chloro?^5 acid, HCIO2 ; and A]/j90-chlorous acid,
HCIO, etc.
Acids are classed as electro-negative, in contra-
distinction to a class of compounds called bases.
The latter are electro-positive, and many of them
are also known as alkalies ; they are the opposite of
acids.
These two classes have a strong love for each
other, and combine to form another class of com-
pounds, which have received the general name of
salts.
Our conception of chemical salts, may be confined
for the present, to the simple statement that they
are, usually solid, neutral substances, produced by
the union of acids with alkalies (or bases), and
named accordingly.
If nitric acid be brought in contact with the al-
kali— or base — sodium oxide, neutral bodies will
result, as will be seen by the following equation :
I^aO + HXO3 = H2O -f :N'a^"03
Sodium Nitric Water. Sodium
Oxide. Acid. Nitrate.
The origin of the names of the first three com-
pounds has already been explained ; the last sub-
stance, it will be noticed, receives its name by
applying the full name of the basic sodium, and
changing the final ic in the name of the acid to ate.
The name derived t'^^sy. ,is; sodium mivate. All
Notation and Nomenclature. 39
salts of nitric acid are nitrates. Salts of nitro?<5
acid are named nitrites. In the same way, all salts
produced by the union of sulphuric acid with a base
are named sulphates. Sulphurous acid produces
salts called sulphi7c5, etc. The names of all salts
whose acids contain more than two elements to the
molecule, such as H^Og, terminate in either ate or
ite; w^hile the names of salts derived from acids
whose molecules contain only two elements, end in
ide. For instance, hydrochloric acid — HCl — bi-
nary, because made up of only two elements, acting
on the basic metal sodium, IN'a, produces a binary
salt whose name should end in ide^ as will be seen
by the following reaction :
:N'a + HCl == H + KaCl
Sodium. Hydro-chloric Hydrogen. Sodium
Acid. Chloride.
In brief, inorganic salts, whose molecules contain
three or more elements, have names which end in
either ate or ite, and salts containing but two elements
have names ending in ide. The reaction between
an acid and a metallic base, usually consists in the
metal taking the place of the H in the molecule of
acid, thus :
f 2H
Hydrogen.
Zn
+
II^SO, =
= ZnSO^
Zinc.
Sulphuric
Zinc.
Acid.
Sulphate
When the oxide of the metal is employed, then, in-
• • •
40
Inorganic Chemistry.
stead of the II escaping free as a gas, it will unite
with the 0 of the base to form water.
ZnO + H2SO4 = ZnSO^ + H^O
Zinc Sulphuric Zinc Water,
Oxide. Acid, Sulphate.
Chemical compounds are definite in their nature,
constant in the ratio of their elements. They fur-
nish no evidence, in physical or chemical proper-
ties, of their composition, except by analysis. I^ot
so with mere mixtures, water and alcohol may be
mixed in any proportion, the mixture exhibiting
properties intermediate between those of its con-
stituents, showing regular gradation according to
the relative amount of water and alcohol that may
be mixed together. A mass of pure water is a
chemical compound, it is rendered appreciable by
our senses, by the union of a great number of
molecules of like construction ; that is, they are
formed by the same kind and number of atoms ;
two atoms of H, and one atom of 0,=Il20; and
inasmuch as the individual atom has its own fixed
and unchangeable weight, it follows that the mass
of matter, made up of homogeneous molecules,
each having the same kind and number of atoms,
must be definite in its nature and constant in the
ratio of its elements.
When two or more compounds are made up of the
same elements then. ^? ^'^^ Ucn4 imperceptibly into each
Notation and Nomenclature. 41
other ^ as in the case of mixtures. Even though
their molecules may differ in constitution, by only
one atom of the same element, their chemical
nature is divided by a sharp line of demarcation;
they are separated, as it were, by an impassable
gulf; and the compounds themselves show no
properties that would leave us to suspect the
presence of their constituent elements. Their
composition is ascertained by analysis, and proven
by synthesis. Carbon-monoxide, CO, and car-
bon-dioxide, CO2, differ only by one atom of O,
and yet they are not at all alike, chemically. The
first is lighter than air, it is highly combustible,
and is not absorbed by a solution of potash. The
second is heavier than air, it is not a combustible,
and is readily absorbed by a solution of potash,
and neither indicates, in the slightest degree, that
it is really a compound of C and 0. One more ex-
ample of, perhaps, more familiar substances, may
better explain the foregoing statement. Mercury
and chlorine form two compounds; mercuric chlo-
ride (HgCl2), is soluble in water; it is a strong
corrosive poison, one centigram (1-6 grain) might
prove a dangerous dose to an adult. Mercurous
chloride (IIg2Cl2) is not soluble in water; it is a
comparatively mild medicine, one hundred centi-
grams (15 grains) Jiii^K^^ fl^b t'a,k^'>l'"\yithout danger.
?•.
• ••••••••«. » ».' ' > '•,
••• ••• ••••• * .» ' ' ' ' > , , , • I
'.* ''• ;.. '...',,/'>' ' .
• .•- ••. ,•, • .
• ••»
• • , •» »
• • *
• • *
42 Inorganic Chemistry.
They are commonly named, corrosive sublimate
and calomel, respectively. Their molecules differ,
as you perceive, by only one atom of Hg, and they
exhibit no properties by which we could suppose
that mercury and chlorine are the elements in their
composition.
We shall consider other important facts in chemi-
cal philosophy after we become acquainted with
t'he principal non-metallic or electro-negative ele-
ments. These, as a class, are more important, from
a chemical standpoint, than are the metallic ele-
ments, inasumuch as one at least, of the former, is
a necessary constituent of all chemical compounds.
Theirintroduction, together with the leading com-
pounds which they form with each other, will be
in the order best adapted, we think, to promote an
intimate and pleasant acquaintance with them.
Oxygen. 43
CHAPTER VIII.
OXYGEN.
Symbol, 0. At. wt. IB. Sp. gr. 1.1056.
Oxygen is a colorless, tasteless, and odorless gas.
It is the most abundant of the elements. It exists
free in the atmosphere, of which it forms about
one-fifth part, and of which it. is the active ele-
ment. Combined with other elements, it consti-
tutes about one-half the weight of the solid crust
of the earth, and eight- ninths of the weight of
water. It is also found as an important element
of animal and vegetable tissues.
Oxygen was discovered by Priestly and Scheele
in 1774, independently of each other. It can be
obtained from any of its compounds, but only those
which can give it up cheaply and in large volume
are the ones employed for such purposes.
The favorite method is to heat the salt, potas-
sium chlorate, in a retort, and collect the escaping
gas over water. We do not regard a detailed de-
scription of experiments necessary here, inasmuch
as they are fully explained by the teacher.
KCIO3 + Heat = KCl -f 30
Potassium Potassium Oxygen.
Chlorate. Chloride.
44 Inorganic Chemistry.
All the 0 in the salt is thus driven off by the
heat, leaving a residue in the retort composed of
K and CI. If three-fourths, by weight, of potas-
sium chlorate be mixed with one-fourth of an
oxide, such as ferric oxide, cupric oxide, -or better,
manganese dioxide (MnOg), decomposition will re-
sult at a lower temperature, although either of the
latter substances does not itself suffer decomposi-
tion. Its influence is said to be due to catalytic
action (?); a question not fully understood.
Oxygen combines, either directly or indirectly,
with all the other elements, except fluorine, to form
binary compounds; (i. e., H2O, CaO, AU2O3, etc.).
When a stngle element unites with O, it is said
to be oxidized, and the process is called oxidation.
Oxidation, like other chemical action, always de-
velops heat. When heat and light are both devel-
oped by the process, the body is said to burn. The
process of combustion will be sufiiciently described
in connection with the element carbon. Ordina-
rily, when a body burns, its elements are simply
uniting rapidly with the O of the air. Bodies
which burn in the air do so with much greater
energy in oxygen alone. If pieces of burning
charcoal or sulphur, or phosphorus, be placed in a
jar of oxygen, the immediate rapid increase in the
amount of heat and light is remarkable. If a
Oxygen. 45
candle with a glowing wick be plunged into a ves-
sel full of oxygen, the candle will at once burst into
a flame. Certain substances, which do not ordina-
rily burn in the air, will do so readily in oxygen.
A thin piece of iron or steel, such as the rubber
saw of the dental labratory or a broken watch-
spring, its surface previously brightened by sand
paper, and having attached to the lower end a bit
of burning match, or spunk, or sulphur, placed
thus in a jar of pure oxygen^ will become ignited,
and evolve exceedingly brilliant corruscations of
heat and light.
The oxygen of the air, although weakened by its
mixture with nitrogen and other gases, is the sup-
porter of ordinary combustion. It is also the sup-
porter of animal respiration; we inhale it with
every breath, and alternately exhale the products
which are formed by it in the body and which are
carried, by the venous circulation, to the lungs, to
be expelled.
The name oxygen, from tw^o Greek words,
meaning a generator of acids, was given it by La-
voisier, in 1778, who was the first to describe the
important part which oxygen plays in the field of
natural phenomena.
It is a necessary element in the formation of
nearly all acids. If we examine with litmus test
46 Inorganic Chemistry.
paper, the jars in which were burned the sulphur
or phosphorus, we will detect an acid reaction :
not sa the contents of the jar in which the iron
burned; the latter fact indicating that all oxides
are not of an acid nature. It is only some of the
oxides of the non-metallic elements, or those of
the metallic elements bordering on the non-metal-
lic, which are classed as acid.
These oxides of the more highly electro-positive
of the metals, such as barium, potassium, etc., are
always basic or the opposite of acid. Barium oxide
and sulphuric oxide will combine directly under
the influence of heat, and thus form the salt
known as barium sulphate.
BaO + SO3 = BaSO^
Barium Sulphuric Barium
Oxide. Oxide. Sulphate.
The acid oxides unite with water to form acids,
as:
SO3 + H2O = H2SO4
Sulphuric Water. Sulphuric
Oxide. Acid.
Basic oxides react with acids to form correspond-
ing salts, as :
CaO + H2SO4 == CaSO^ + H2O
Calcium Sulphuric Calcium Water.
Oxide. Acid. Sulphate.
There is a third class of oxides called neutral^ of
which water is a good example. They are neither
acid nor basic, but some of them may act in either
Oxygen. 47
capacity, according to circumstances. When cal-
cium oxide, which is strongly basic, is mixed with
water, the latter acts as an acid oxide, resulting in
the production of the salt caled calcium hydrate,
or hydroxide.
CaO + H2O = Ca(H0)2
Calcium Water. Calcium Hydrate,
Oxide.
It will be seen, on the contrary, by referring to
the proper equation preceding, that water acting
on SO 3 takes the part of a basic oxide, in forming
the molecule of sulphuric acid, or hydrogen-sul-
phate (H2SO4).
Ozone. — When an element is capable of existing
in more than one state it is called allotropic. Oxy-
gen is an allotropic element. It exists in a passive
and in an active state. Passive oxygen is the kind
we have been studying. Active oxygen is named
ozone. The latter substance is far more energetic
as an oxidizing agent than ordinary oxygen. It is
the great natural disinfectant, destroying by oxi-
dation the infectious matter that appertains to the
metamorphosis of animal and vegetable tissues.
Ozone is developed in a variety of ways :
Ist. By heat; as when platinum wire is merely
heated in the air.
2nd. By light; as when CO2 is decomposed by
living plants, by the aid of sunlight ; and when
48 Inorganic Chemistry.
essential oils are exposed to sunlight and summer
temperature.
3d. By electricity; as when the silent electric
discharge takes place in the air, or in oxygen gas,
and by electrolysis of water.
4th. By slow oxidation ; as when a clean stick of
phosphorus is partially exposed to the air, or
when a strongly heated glass rod is placed in va-
por of common ether.
5th. By rapid combustion; as when a vigorous
blast of air forces the top of a Bunsen flame into
a large beaker, the contents of the beaker will give
the ozone reaction.
A good test for the presence of ozone is paper
moistened with dilute solution of potassium iodide
(KI) and starch. The ozone, by uniting with the
potassium, sets the iodine free, which turns the
starch to a deep blue color.
Ozone is an irritating poison to animal tissues,
if inhaled in quantity. Unlike ordinary oxygen,
ozone has a decided odor, hence its name, which
means to smell. It is one-half as heavy again as
oxygen ; its density being 24, and that of the lat-
ter 16. In fine, ozone is oxygen modified into a
condition of intense activity. All its combina-
tions with other individual elements produce only
oxides.
Hydrogen. 49
CHAPTER IX.
HYDROGEN.
Symbol H. At. wt. 1. Sp. gr. 0.0693.
Hydrogen is a colorless gas, without taste or
smell. It is the lightest body known, being about
foui'teen and a half times lighter than air. The
spectroscope shows that hydrogen is a constituent
of the sun, the fixed stars and, largely of the celes-
tial nebulae. It is found occluded in meteoric iron.
Hydrogen is found free in volcanic gases. Com-
bined with oxygen, it forms the compound water ;
hence its name, given it by Lavoisier, signifying
'^ generator of water." It is an important element
of animal and vegetable tissues, and of mineral
oils.
Hydrogen was known in the sixteenth century,
but was first accurately described by Cavendish in
1766. It can be obtained from its compounds by
various methods, but is usually prepared by action
of zinc, on dilute sulphuric acid, or hydro-chloric
acid.
Zn -t- 2IIC1 = ZnCl2 -h 2H
Zinc. ir.Vflrochloric Zinc; Hydrogen.
Acid. Chloride.
The gas may be collected over water or by dis-
5
50 Inorganic Chemistry,
placement of air. Although hydrogen is the
lightest substance known, it is undoubtedly the
vapor of a highly volatile metal. We describe it
thus early, in connection with the non-metals, be-
cause of the wonderfully important place it holds
in the family of elements. On account of the high
diffusive power and combustibility of hydrogen,
great precaution should be observed in experi-
menting with the gas, in order to avoid the danger
of explosion. Heated to a temperature of about
500°C. (982°F.), it unites with oxygen : the union
of these gases developing the highest temperature
produced by chemical action. One gram of hydro-
gen in oxidizing, or burning, will raise the tempe-
rature of 34,462 grams of water from 0° to 1° ; that
is equal to 34,472 heat units. The compound which
it forms by direct union with oxygen is water
(H2O), the molecule of which contains two parts
by weight, or two atoms of hydrogen, and sixteen
parts by weight, or one atom of oxygen. The mol-
ecular weight of any substance is the sum of the
atomic weights^ and inasmuch as the two atoms of
hydrogen weigh two, and the one atom of oxygen
weighs sixteen, the molecular weight of water
must be 2 + 16 = 18.
Water is the most abundant of chemical com-
pounds. Notwithstanding its neutral nature, being
Hydrogen. 51
neither acid nor alkali, it is a very active substance,
clieniically. It leads all other liquids as a solvent.
With but few exceptions, solids will dissolve more
easily in warm than in cold water, while certain
gases, as 0, N2O, CO2, etc., are more soluble in
cold water than in warm.
Pure water is tasteless, ordorless, and, when in
small quantity, colorless. It exists in certain com-
pounds as w^ater of crystallization, enabling them to
assume a definite crystalline form, as, natural gyp-
sum, blue-stone, etc. When sufficiently heated,
this water is driven out, and the substance loses its
crystalline form, but will take up water again most
readily, as in the case of plaster of parfs.
Oxygen and hydrogen may be induced to unite
in the proportion of two atoms of each, to form
hydrogen dioxide (H2O2), commonly called perox-
ide of hydrogen. It may be prepared by acting
on barium dioxide, held in suspension in water, by
either of several acids, as :
Ba02
+
Ha CO J =
=: BaCOg
+
H.O^
Bftrium
Carbonic
Barium
Hydrf)gen
Dioxide.
Acid,
Carbonate.
Dioxide.
Approximately pure, peroxide of hydrogen is
colorless; it possesses, however, an ozone-like odor
and a peculiar metallic taste. It is never used in
medicine, or the arts, in the undiluted form, but is
usually held in solution in glycerine or water. A
52 Inorganic Chemistry.
"ten volume " preparation of it will give off ten
times its o^yn volume of free oxygen. The tem-
perature of summer heat will cause the molecule
(H2O2) to decompose, one of the O atoms escap-
ing. The solution should, therefore, be kept in a
cool place, except when in use.
It is an excellent germicide and disinfectant, de-
stroying the infectious matter by the activity of
the nascent oxygen which it supplies.
An element is nascent at the time it is set free
from combination, and is then more anxious to
unite with other bodies than when it is in its ordi-
nary state.
A trace of acid (sulphuric or phosphoric) is us-
ually found with the peroxide of hydrogen solu-
tion, to render the preparation more stable ; and-
the results of experiments with the peroxide on
pus, bone, etc., are often misjudged on account of
the acid present.
Chlorine. 53
CHAPTER X.
CHLORINE.
Symbol, CI. At. wt. 35.5. Sp. gr. 2.46.
Chlorine was discovered by Scheele, in 1774. Its
elementary character was proven by Dav}^ in 1810,
who gave it the name it bears, w^hich signifies its
color, ^' greenish yellow^
Chlorine is not found free in nature. It exists
abundantly, however, in combination with Na., Ca.,
K., and Mg., in sea water, and saline springs. Vast
deposits of solid sodium chloride, or common salt,
are found and mined; it being a necessary article
of every day use.
Chlorine is usually obtained in quantity by gently
heating together certain proportions, indicated by
their molecular weights, of the two first following
compounds :
iMn02 I 4IIC1 =^ 2II2O + MnCl2 + 2CI2
Manganese Hydrochloric Water Manganese Chlorine
Dioxide. Acid. Chloride.
It may also be obtained, sufficiently pure for
ordinary experiment, by acting on common bleach-
ing powder with dilute sulphuric acid. The re-
action of these substances, being rather complica-
ted, will not be considered at this time.
54 Inorganic Chemistry.
Chlorine is a greenish-yellow gas, of an intoler-
able suffocating odor and astringent taste. When
subjected to a cold of 40°, or at a common temper-
ature, to a pressure of four atmospheres — 60 pounds
to the square inch, it condenses to a yellow liquid
of sp. gr. 1.38.
Water will dissolve nearly three times its own
bulk of chlorine, the solution acquiring the color
and odor of the gas; it is known as aqua Mori,
and is employed to advantage in practice, as a dis-
infectant, and to bleach discolored teeth. Aqua
chlori, exposed to the influence of light, decom-
poses according to the following equation :
H2O, 2C1 = 2HC1 f O
Water. Chlorine. Hydrochloric Oxygen.
Acid.
It must, therefore, be preserved in a dark place.
Chlorine acts indirectly as a bleaching agent and
disinfectant through its love for the hydrogen of
water, letting the 0 go free, vide the above equa-
tion, which latter element, in its nascent state, at-
tacks the coloring matter, or infectious matter, as
the case may be, forming with either, new com-
pounds that are destitute of color, or free from the
germs of disease. Mineral colors, as a rule, are
not affected by chlorine.
The affinities of chlorine are exerted mainly
toward hydrogen and the metals. If a lighted
Chlorine. 55
candle, the combustible elements of which are C
and H^ be placed in a jar tilled with chlorine,
dense volumes of smoke will be evolved, owing to
the chlorine taking up with the H of the candle,
resulting in HCl, and the rejection of the C, which
escapes as smoke. A piece of tissue paper moist-
ened with warm oil of turpentine, and thrust into
a jar of chlorine, shows the same phenomenon.
Finely divided arsenic, or antimony, or thin leaves
of copper or bronze, or a bit of phosphorus, at
ordinary temperatures, and sodium, at a higher
temperature, will burn in chlorine, forming a chlo-
ride in each case. A mixture of hydrogen and
chlorine, exposed to the sunlight, will unite with
explosive violence. In tine, chlorine unites, either
directly or indirectly, with all the elements, form-
ing a chloride with each, some of which, however,
are very unstable compounds.
Hydrogen Chloride. — Chlorine and hydrogen
unite with each other in but one proportion. The
compound is generally called hydrochloric acid.
It is a colorless gas, of a pungent odor, is irrespi-
rable, though not so irritating as chlorine, and is
noncombustiblc. Its specific gravity is 1.264, its
density (II as unity) is 18.25. Subjected to cold
and pressure, it condenses to a colorless liquid, of
specific gravity 1.27.
56 Inorganic Chemistry.
Hydrochloric acid is manufactured on a large
scale by heating togetlier quantities of common salt
(;N"aCl) and strong sulphuric acid, as indicated by
the following equation :
2:N'aCl + H2SO4 = :^a2S04 + 21101
Sodium Sulphuric Sodium Hydrochloric
Chloride. Acid. Sulphate. Acid.
The gas (HCl) is very soluble in water. A given
volume of wat'er will dissolve 450 volumes of the
gas, and a more or less saturated aqueous solution
becomes the hydrochloric or muriatic acid of com-
merce, possessing the same acrid and acid proper-
ties of the gas itself. The presence of the w^ater,
however, is not expressed in the reactions of the
acid, so that the formula HCl means either the gas
alone, or its solution in water.
Hydrochloric acid is an important substance. It
dissolves many of the metals, such as aluminum,
tin, iron, zinc, etc., the reaction consisting in the
metal supplanting the H of the acid, resulting in
free hydrogen and metallic chlorides. As before
alluded to, as a rule, wnth some exceptions, when-
ever any acid attacks a metal, a quantity of H
equivalent to the metal escapes free, the metal
uniting with the residue of the acid to form a salt
of the metal in question, as :
2HC1 + Fe = 2H + FeCl2
Hydrochloric Iron. Ferrous
Acid. Chloride.
Chlorine. 57
Hydrochloric acid is therefore the type of all
chlorides.
It is one of the solvents in the gastric juice, and
is probably developed there by the influence of a
special ferment^ which, in some way not yet under-
stood, induces the CI of the sodium chloride, one
of the proximate principles of the body, to unite
with the H of the water present, or some other
hydrogen compound, or vice versa. The child of
the union would, of course, be HCl.
Dr. George Watt, of Ohio, the recognized origi-
nator of the chemical (per se) theory of dental de-
cay, proposes hydrochloric acid as the active cause
of the brown, or common variety of decay of teeth.
The structure of a tooth is generally divided into
animal (matrix) and mineral portions ; the latter
consisting mainly of calcium phosphate and cal-
cium carbonate.
If hydrochloric acid is formed in the mouth, in
accordance with the afflnities by which it is devel-
oped in the gastric juice, a chemical analogy by
no means improbable, the nascent individual mole-
cules of the acid would simultaneously decompose
the calcium carbonate, and dissolve the calcium
phosphate.
CaC03
+
2IIC1 —
CaCL,
Calcium
Carbonate.
Hydrogen
Chloride.
Calcium
Chloride
58 Inorganic Chemistry.
The calcium phosphate of the tooth, although
riot entering into the equation, loses its structural
integrity by solution, and the animal portion more
or less remains in situ.
There are compounds of chlorine, hydrogen, and
oxygen, the elements we have especially introduced
thus far, which are worthy of some consideration
at this time. They are all acid in their nature,
and may be regarded as oxides of HCl :
HCIO4, Perchloric acid.
HCIO3, Chloric acid.
HCIO2, Chlorous acid.
HCIO, Hypochlorous acid.
The salts of these acids are known, seriatim, as
perchlorates, chlorates, chlorites, and hypochlo-
rites. The first and third class are of no special
interest, but the chlorates and hypochlorites are
used largely as important agents in chemistry and
materia medica ; they will be considered later on
in connection with certain metals. There are three
oxides of chlorine, CI2O, CI2O2, CI2O4, which are
highly explosive, but possess no other interrst.
Chlorine is the principal member of a group of
elements which contains also iodine, bromine, flu-
orine. They are all called halogen elements, because
the sea is the principal source of chlorine, iodine,
Chlorine. 59
and bromine ; so great is the resemblance to each
other, in their chemical nature, that a description
of one, as, for instance, chlorine, will serve in a
measure for that of the others.
60 Inorganic Chemistry.
CHAPTER XI.
IODINE.
Symbol, I. At. wt. 127. Sp. gr. 4.95.
Iodine is obtained from the ash of sea weeds.
It is a dark bluish solid, consisting of rhombic
scales, of a metallic luster. It melts at 107° (225°
F.), and boils at 180° (356°F.), evolving a magnifi-
cent violet vapor, of specific gravity 8.72.
Iodine requires 7,000 parts of water to dissolve
it. It is freely soluble in -an aqueous solution of
its most important compound, potassium iodide,
and in alcohol, ether, chloroform, and carbon di-
sulphide. It is not as active, chemically, as chlor-
ine, though it combines directly with most of the
metals forming iodides. It strikes, with a solution
of starch, a deep blue color, so intense that one
part of iodine in 300,000 of water can be detected
by the starch test.
Iodine, both free and in combination, is a valu-
able therapeutic agent,* as a resolvent and anti-
septic; it is also largely used in photography.
*Brief allusion to medicinal qualities, while considering the
non-metallic elements, is excusable, as we hope to deal justly
by their compounds in materia medica.
Bromine. 61
BROMINE.
Symbol, Br. At. wt. 80. Sp. gr. 3.187.
Bromine is prepared from sea water and saline
springs. It is a red-brown liquid of disagreeable
odor, hence its name. Heated to a temperature
of 63° (145°F.), it boils, yielding a deep red vapor,
of specific gravity 5.5. Cooled to —22° (— 8°F.), it
becomes a crystalline lead-gray solid. One part of
bromine requires 33 parts of water to dissolve it.
It is a corrosive poison ; exerts a strong bleaching
power. It is, chemically, less active than chlorine,
but more so than iodine. Some of the metals will
burn in its vapor, producing bromides. It is used
extensively in photography, and some of its com-
pounds are of therapeutic value.
FLUORINE.
Symbol, F. At. wt. 19. Sp. gr. .
Fluorine is a constituent of a substance known
as fluor spar, meaning, I flow, because this com-
pound— CaF2 — is used as a flux in the reduction
of some metals.
Free fluorine (but recently isolated) is a colorless
gas, of pungent odor, and exceedingly corrosive.
62 Inorganic Chemistry.
It is especially distinguished as the only element
which refuses to unite with oxygen ; and although
in its free, and therefore inactive state, it shows
only slight affinity toward silicon, the latter ele-
ment is violently attacked by nascent fluorine,
which is developed by bringing together hydro-
fluoric acid and a silicon compound, such as glass.
Hydrofluoric acid, HF, is usually prepared by re-
action of calcium fluoride and sulphuric acid, in a
vessel of platinum or lead.
CaF2 4- H2SO4 = CaSo4 + 2HF
Calcium Sulphuric Calcium Hydrofluoric
Fluoride. Acid. Sulphate. Acid.
This acid, when pure, is a colorless gas, but in
its ordinary condition it is dissolved in water. It
is of peculiar interest, because it is the only sub-
stance that freely attacks such compounds of sili-
con as glass, and porcelain teeth. It is useful in
the arts, for etching on glass.
HALOGEN ACIDS.
The analogy between the halogen elements,
chlorine, iodine, bromine, and fluorine, is best ex-
emplified by their binary hydrogen compounds :
Hydrochloric acid HCl
Hydriodic acid HI
Hydrobromic acid HBr
Hydrofluoric acid HF
Halogen, 63
The first and last of these acids have already
been sufficiently described. The second (HI) and
third (HBr) are also pungent, colorless gases, yqyj
soluble in water, and are used in practice in aque-
ous solution. They are the prototypes of all
iodides and bromides, as hydrochloric and hydro-
fluoric acids are the types respectively of chlorides
and fluorides. There are also oxy acids of iodine
and bromine analogous to those of CI. The prin-
cipal ones have the formula of HIO3 and HBrOg,
corresponding to chloric acid HCIO3. Their salts
are called iodates and bromates.
64 Liorganic Chemistry.
CHAPTER Xir.
NITROGEN.
Symbol, K At. wt. 14. Sp. gr. 0.971.
Nitrogen is a colorless, odorless, and tasteless
gas. It was discovered by Rutherford in 1772,
and received its name because it was found to be a
necessary constituent of niter.
Nitrogen and oxygen are the principal compo-
nents of the atmosphere; four-iifths of nitrogen,
and one-fifth of oxygen. Although not chemically
combined, their intimate mixture in the above
proportions obtains throughout, the nitrogen serv-
ing to retard within reasonable bounds the energy
of oxygen.
If a piece of phosphorus be. burned in a given
volume of air, confined over water, the phosphorus
takes up all the oxygen, the water rapidly absorbs
the compound so formed, and the nitrogen remains
alone, comparatively pure.
Nitrogen is not a supporter of combustion, nor
of respiration; it is, in fine, remarkably inert,
showing little disposition to unite directly with
other elements, although its compounds are nu-
merous, and some of them of exceeding energy.
Nitrogen. 6^5
Besides its existence in the atmosphere, it is found
\\\ nature in the compounds known as nitrates, and
in ammonia, and is also an essential element of
certain animal and vegetable substances.
Ammonia. — Ammonia is a gaseous compound of
nitrogen and hydrogen (NHg). It is formed slowly
at common temperatures, by putrefactive decom-
position of animal and vegetable substances con-
taining nitrogen; more rapidly when clippings of
horns, hoofs, or hides, or other animal tissue, are
subjected to heat — hence the name sometimes
given it of "spirits of hartshorn." Many of its
compounds are now obtained by the destructive
distillation of coal, in the manufacture of illumin-
ating gas. Ammonia itself is prepared by gently
heating together a salt known as " sal ammoniac,"
or ammonium chloride, and calcium oxide (quick-
lime).
(NH4CM)2 + CaO = CaCl^ 'H2O + 2NH3
Am. chloride. Calcium Calcium Water. Ammonia.
Oxide. Chloride.
Ammonia is a colorless gas, of specific gravity
0.59. It is possessed of a peculiar pungent odor,
by which its presence may be detected. Subjected
to a pressure of a hundred pounds to the square
inch, at 10° (50°F.), it condenses to a clear liquid,
of specific gravity 0.76. The liquid ammonia is
highly volatile, and in passing into the gaseous
6
66
Inorganic Chemistry.
state, by removal of pressure, it absorbs a large
amount of heat. It is for this reason, as well as
its cheapness, that ammonia is employed in the
artificial production of ice.
Ammonia gas is exceedingly soluble in water ;
one volume of water at 15° (59°F.) will dissolve
783 volumes of the gas. This solution, further di-
luted, is the well known '' aqua ammonia" of com-
merce. It evolves the gas again upon iieating, or
on exposure to the air. It is a stimulant when
slightly inhaled, and is often so employed in non-
complicated syncope.
Ammonia, whether in the gaseous form or in
the aqueous solution, is strongly alkaline; it unites
with and neutralizes the strongest acids, forming
with them compounds, called salts of ammonia.
The hydrogen of the acid, in such combination, is
not driven out, but seems to take up intimately
with the ammonia itself, apparently producing, in
the reaction, an unsatisfied group (I^H4), which
has received the name of ammomum., because it
acts in many cases like an atom of some of the
metals. Thus:
OTI3 + IICl = (:N'H4)C1,
Ammonia. Hydrochloric Ammonium
Acid, Chloride.
analogous to sodium chloride, IRaCl. Ammonium
chloride was first prepared by the Arabs of the
Nitrogen, 67
Libyan deserts, as a substitute for common salt, by
heating camel's dung. They named it '' sal am-
moniac"— salt of Ammon — in honor of Jupiter
Ammon, whom they worshiped, and from w^hich
the name ammonia is derived. Ammonium iodide
and ammonium bromide are analogous salts.
Nitrogen and oxygen unite wnth each other in five
proportions. Their compounds have the following
names iind formulas:
Nitrogen pentoxide (or miric oxide) ^2^5
Nitrogen tetroxide ^2^4
Nitrogen trioxide ^2^3
Nitrogen dioxide ^2^2
Nitrogen monoxide (or mXvous oxide).... N2O
The first and third are acid oxides; they will
combine with water to form acids. Nitric oxide,
sometimes called nitric anhydride, may be prepared
by action of chlorine on solution of silver nitrate:
2AgN03 + 2C1 = 2AgCl + 0 + l^^O,
ArKeutura Chlorine. Argentum Oxygen. Nitric
Nitrate. Chloride. Oxide.
Nitric oxide is a colorless crystalline solid, of
unstable, explosive qualities. It reacts energetic-
ally with water, producing nitric acid :
N2O5 + [1,0 = 2IINO3
Nitric oxide. .V>»ter. Nitric acid.
Nitric acid was known to Geber in the eighth
century, and described by Raymond Lully in 1225.
Cavendish, in 1785, first determined its true compo-
68 Inorganic Chemistry.
sition. It is formed in nature in various ways ; by
strong electric currents passing through air; by
ozone acting upon the nitrogen, or the ammonia in
the air, or on nitrogen dioxide, trioxide, and tetrox-
ide, in the presence of water.
When animal or vegetable matters containing
nitrogen decompose, ammonia is produced, and
this compound, in presence of weak alkaline bases,
is decomposed by nascent oxygen, or by ^ ozone,
into water and nitric acid :
NH3 + 04 = H2O + HNO3
Ammonia. Water. Nitric acid.
A process of manufacture, following these lines,
will result in the development of artificial beds of
niter.
In the arts, however, nitric acid is always pro-
duced by "heating sulphuric acid with either potas-
sium nitrate or sodium nitrate.
An equation will best explain the reaction :
KN03
+
H,SO, =
= HKSO4 +
HNO3
Potassium
Sulphuric
Hydropotassium
Nitric
Nitrate.
Acid.
Sulphate.
Acid.
Nitric acid, commercially known as aqua fortis,
when pure, is a fuming, colorless, corrosive liquid,
having a specific gravity of 1.52 ; chemically, it is
an exceedingly energetic body, attacking most of
the metals, and forming with them salts called
nitrates, nearly all of which are soluble in water.
Nitrogen. 69
xTitrogenous animal substances, as wool, silk,
and parchment, are colored a deep yellow by it.
And many non-nitrogenous substances, as cotton,
sugar, and glycerine, are converted into explosive
bodies by- nitric acid.
By virtue of its oxidizing power, many remark-
able reactions are induced to take place. Gold is
not affected by any single acid, except slightly by
selenic acid, but if the two acids, hydrochloric and
nitric, be mixed and gently heated, the nitric acid
will give up enough oxygen to oxidize all the
hydrogen of both acids, setting the chlorine free,
which latter element, in its nascent state, readily
unites with the gold present, forming the soluble
AUCI3.
9HC1 + 3HXO3 = 6H2O + 3N0C1 + 2CI3.
2Au ^ 2CI3 = 2AUCI3.
The XOCl is of no importance, some authorities
claiming that the residue of nitrogen and oxygen
remain together as 3N0, letting all the -chlorine
escape to the gold.
Nitric acid is believed by many experimenters to
be the cause of the rapid, or white, variety of decay
of teeth. This idea does not conflict in the least with
the so called "germ theory" of decay, inasmuch as
the ferment of nitric acid has been discovered re-
cently. The manner of its formation in the re-
70 Inorganic Chemistry.
cesses of the teeth, as described by Dr. Watt, is
owing to the decomposition of nitrogenous sub-
stances (putrefaction), developing simultaneously
ammonia and nascent oxygen, which immediately
react on each other, resulting in the oxidation of
the hydrogen and nitrogen into nitric acid. The
action of any acid on the tooth, in forming caries,
must occur at the place, and at the instant, of its
development ; that is, molecularly. It is not con-
ceived that caries are formed only by a general
acid nature of the oral fluid ; on the contrary, the
latter may remain neutral, or be even decidedl}^
alkaline. The favorite trysting place of the fer-
ments, in dental caries, is usually a quiet nook,
unfrequented by the brush, wdiere the cultures
consisting of organized debris, are changed into
simpler bodies, and many of these, ultimately, into
poisonous ptomaines and acids.
Little need be said of the dioxide, trioxide, and
tetroxide of nitrogen. The dioxide (N2O2) is able
to take up oxygen from the air and is thereby con-
verted into the tetroxide, ^^2^4 5 ^^^^ latter sub-
stance is a good oxidizing agent, as we shall learn
by and by. The trioxide (IS'gOg) is the anhydrous
oxide of nitrous acid, as the pentoxide (^2^5) ^^^ of
7iitric acid ; the salts of nitrous acid are called ni-
trites, as those of nitric acid are called nitrates.
Nitrogen. 71
Nitrous Oxide. — Or nitrogen monoxide. Mole-
cular formula, XgO. Sp. gr. 1.527.
Nitrous oxide was discovered by Priestly in 1776.
Sir Humphry Davy, in 1807, described its exhilar-
ating properties, and in 1845 Dr. Horace Wells, aii
American dentist, of Hartford, Conn., employed it
as an anaesthetic, and in so doing, became the orig-
inal, genuine discover of ancesthesia.
Nitrous oxide is prepared by carefully heating
in a retort the salt known as ammonium-nitrate.
The retort is connected by means of glass and rub-
ber tubing with a series of wash bottles, the tube
ending in a receiver placed over water :
NH4NO3 -f Heat =z 2H2O + N2O
Am Nitrate Water. Nitrous
Oxide.
The wash bottles usually contain water, potas-
sium hydrate, and ferrous sulphate; these sub-
stances neutralize any traces of the higher oxides
of nitrogen that may be evolved, and which other-
wise would pass through with the nitrous oxide into
the receiver.
Nitrous oxide is a colorless, odorless gas, with a
slightly sweetish taste. Subjected to a pressure of
45 atmospheres at 0° (32°F.), it condenses to a
clear, mobile liquid of specific gravity 0.9; this
liquid freezes into a snowlike mass, by the effect of
its own evaporation, when allowed to escape freely
72 Inorganic Chemistry.
into the air. Its boiling point is — 88°(— 126°F.) ;
its freezing point is — 101°(— 150°F.).
The gas is quite soluble in alkaline solutions ; it
is also soluble in water; more so in cold water than
in warm ; 100 volumes at IS*' (60°F.) will dissolve 78
volumes of the gas. It possesses decided disin-
fectant and antiseptic properties. Impure water,
containing much organic matter, becomes pure and
sweet, and remains so indefinitely, after dissolving
even a small quantity of the gas.
Kitrous oxide is readil}^ decomposed by the heat
of burning bodies, letting its oxygen go to support
the combustion. In this way combustible bodies
will burn in it, much like we saw them do in oxygen,
with greater energy than in the air. In this way,
also, it supports animal respiration to a certain
point. One of the products it develops in the
body (CO 2) can not escape, as in ordinary breath-
ing; the unavoidable retention, therefore, of this
product, in the central and other capillaries, in-
duces more or less asphyxia, according to the
quantity and rapidity of the inhalation of the un-
mixed gas.*
Nitrous oxide is now largely supplied to the pro-
fession, condensed to the liquid state in metallic
cylinders.
* The possible chemico-physiological action of nitrous oxide
will be considered with the compounds of iron.
Sulphur. 73
CHAPTER XIII.
SULPHUR.
Symbol, S. At. Wt. 32. Sp, gr. 2.04.
Sulpliur (brimstone) has been known from the
earliest historic ages. It is found free in certain
volcanic regions. It is found also in nature in
combination with other elements, as iron, copper,
mercury, zinc, lead, arsenic, antimony, and hydro-
gen. The sulphides are important natural com-
pounds, and with oxygen and certain metals, such
as calcium, magnesium, barium, strontium, and
sodium, it is found in the class of salts known as
sulphates. Sulphur is an essential element of ani-
mal bodies, and of many vegetables.
It is a yellow, brittle solid, freely soluble in car-
bon disulphide, but not in water; it melts at
114°(237°F.), and boils at 448°(824°F.) ; it is taste-
less and odorless, and is not a conductor of heat or
electricity.
Sulphur is capable of crystallizing in two distinct
forms; it is, therefore, said to be dimorphous. The
natural crystals, and those deposited from solu-
tion of the element in carbon disulphide, are rhom-
bic octohedra, while melted sulpliur, if allowed to
7
74 Inorganic Chemistry,
cool slowly, will assume a prismatic form. An
amorphous (non-crystalline) variety is obtained by
pouring melted sulphur into cold water.
When heated in the air to 260°(500°F.), sulphur
takes fire, and burns with a pale, lambent flame,
forming SOg ; and certain metals, if heated in
its vapor, will burn readily, forming sulphides. It,
therefore, shows an aflinity for oxygen and various
metals; it also unites directly with carbon.
Dental rubbers contain from 15 to 20 per cent of
" flowers of sulphur," which enables the caoutchouc
to become vulcanized into a hard material. Sul-
phur has been suggested as a filling for root
canals, being fused therein by heated instruments,
and for setting crowns.
Sulphur unites with oxygen in two proportions.
When sulphur is burned in the air, or in oxygen,
the dioxide (SO2) is formed; this substance is a
good disinfecting and bleaching agent, being a de-
oxidizer, able to take away oxygen from certain
deoxidizable bodies, which destroys their identity.
Sulphur dioxide is an acid oxide; united with
water, sulphurous acid is the result :
SO2 + H2O = H2SO3
■ Sulphurous acid.
The salts of this acid are named sulphites.
The other oxide of sulphur is the trioxide (SO^)
Sulphur. 75
or sulphuric oxide. It is usually prepared by oxi-
dizing sulphurous oxide — the dioxide SO2. Sul-
phur trioxide is a white wax-like solid, of a silky,
librous appearance, somewhat resembling asbestus.
It unites with water, giving rise to great heat, pro-
ducing sulphuric acid:
SO3 + H2O = H2SO4
Sulphuric Acid.
Sulphuric acid, hydrogen sulphate, next to water
itself, is perhaps the most generally useful sub-
stance in chemistry: it occurs free in the waters of
certain springs and rivers, and in the saliva of cer-
tain mollusks, and is the type of all sulphates.
The preparation of sulphuric acid — also known
as oil of vitriol — involves several simple chemical
reactions :
1st. The burning of sulphur in the air to obtain
sulphurous oxide SOg.
2d. The presence of nitric acid (2H]Sr03) which
supplies nitrogen tetroxide ^2^4-
3d. The latter compound gives oxygen to the
SO2, changing it into SO3, and is itself reduced to
nitrogen dioxide N2O2.
4th. Water, heated by the burning sulphur,
unites with the SO3, producing sul[)liuric acid.
5th. The taking up of oxygen from the air by
76 Inorganic Chemistry.
the uitrogen dioxide, which thus serves as a carrier
of oxygen.
The whole process may be more easily under-
stood by referring to the following equations :
S H- 20 = SO2.
2SO2 + N2O4 r=r 2SO3 -h ^202-
SO3 + H2O = H2SO4.
K2O2 -f 20 = N2O,.
Inasmuch as the process is continuous and si-
multaneous, from the burning of the sulphur to the
deposition of the acid on the floor of the leaden
chamber, it is probable that other and complicated
reactions take place. The above explanation, how-
ever, is the one generally accepted as the simplest
view that can be taken in the premises and is, at
least approximately, correct.
Sulphuric acid is a colorless, oily liquid, of spe-
citic gravity about 1.85. Freezes at — 26° (— 15°F.)
and boils at 328° (622°F.). It has a strong aflanity
for many of the metals. It is always thirsty for
water, their union evolving great heat. It absorbs
moisture from the air and from other gases, and is
therefore often used as a drying agent. Its general
action on organic matters is to dehydrate them,
that is, to take from their substance the elements
oxygen and hydrogen, and induce them to combine
to form water, that its thirst may be satisfied.
Sulphur, 77
Sulphuric acid is more than likely involved in
the condition known as " black decay " of teeth.
Its production in situ is probably due to the energy
of nascent oxygen on hydrogen sulphide (H2S),
these being evolved from the organized debris in
contact with the tooth, Orud which is said to un-
dergo decomposition by the influence of some not
yet detected special form of bacteria.
The phenomena of " black decay " really seem to
be an arrest of the destructive proceedings of some
active solvent, previously at work. Any well-
marked specimen of this form of caries represents
the surface of the cavity of a dark brown or black
appearance, hard, and sometimes polished, and
which is comparatively immune from further decay.
The limiting action of sulphuric acid on tooth
structure explains the above physical characteris-
tics. Its molecules, at their birth, attack the
earthy portion, forming insoluble calcium sulphate
(CaSO^), and at the same time dehydrating the
animal or gelatinous portion, which is mainly made
up of carbon, hydrogen, and oxygen ; these two
latter elements are withdrawn, as already alluded
to, leaving the indestructible carbon as a residue,
to be incorporated with the insoluble sulphate,
producing thus a protecting covering to the unaf-
78 Inorganic Chemistry.
fected parts beneath against fnrther inroads both
of the causing agent and other solvents.
A gaseous compound of sulphur and hydrogen
(sulphuretted hydrogen, dihydrogen sulphide, sul-
phydric acid, etc., U2S), is found in nature, and
also largely employed in the labratory as an im-
portant re-agent in classifying the metals, according
as their sulphides are either soluble or insoluble in
acid and alkaline solutions.
Quite a number of oxygen acids of sulphur are
known as thionic acids; their molecules contain 2
atoms of H and 6 of 0, and 2, 3, 4, and 5 atoms of
S, respectively. They are, however, of no general
or special interest to us.
SELENIUM.
Symbol, Se. At. wt. 79. Sp. gr. 4.5.
Selenium, named in honor of the moon, belongs
to the less abundant elements. It is occasionally
found free, but generally in company with sulplwir,
and in the selenides of silver, mercury, lead, and
copper. It unites with hydrogen to form a gaseous
compound (H2Se), analogous to sulphuretted hy-
drogen, of an extremely nauseous odor. It forms
acids corresponding to those of sulphur: selenious
acid (HgSeOg), and selenic acid (H2Se04), the lat-
ter being the only single acid that will even spar-
ingly attack gold.
Tellurium. 79
TELLURIUM.
Symbol, Te. At. wt. 128. Sp. gr. 6.2.
Tellurium, named from tellus, the earth, is a
rarer element than selenium. It occurs free in
small quantities, and in the tellurides of mercury,
silver, lead, bismuth, and gold. In Colorado, the
tellurides of silver and gold are important ores.
Physically, it resembles the metals, but in its chem-
ical nature, it is closely related to sulphur and
selenium.
The three elements form similar compounds —
with hydrogen (Il2Te), and with oxygen (Te02Te
O3), and corresponding acids (H2Te03, Il2Te04).
80 Inorganic Chemistry,
CHAPTER XIY.
PHOSPHORUS.
Symbol, P. At. wt. 31. Sp. gr. 183—214.
Phosphorus was discovered by Brandt in 1669.
It does not occur free in nature, but exists in com-
bination, generally as phosphates. It is a constit-
uent of teeth, bones, and other tissues, and is
obtained in our food, mainly from the seeds of
plants.
Phosphorus is prepared from the ash of bones
by treatment with sulphuric acid and charcoal. It
is a yellow, waxy, translucent solid, easily cut with
a knife, is luminous in the dark, by slow oxida-
tion. At 50° (122°F.) it takes fire, and burns with
great brilliancy. Its field of energy is very wide,
as it combines with nearly all the elements, C and
^N" being exceptions. It is soluble in carbon disul-
phide, but not soluble in water, in which it must
be preserved. As phosphorus is an active, insidi-
ous poison, workmen in match factories, by neg-
lecting their teeth, are often afilicted with dental
caries and necrosis of the lower jaw. Oil of tur-
pentine and alkaline mouth washes are the best
antidotes.
Phosphorus. 81
Phosphorus, heated to 250° (482°F.), is converted
into a red powder of sp. gr. 214. The red variety
is not soluble in carbon disulphide, is not poison-
ous, has no odor, and does not oxidize in the
air, and will not take lire until heated to 260°
(500°F.).
There are two oxides of phosphorus : that pro-
duced by oxidation, phosphorous oxide (P2O3),
and that produced when phosphorus is burned in
the air or in oxygen, phosphoric oxide (P2O5).
Phosphoric oxide, united with water, forms phos-
phoric acid :
P2O5 + 3H2O =: 2H3PO4
There are several kinds of phosphorus acids,
but two or three only need be mentioned.
Ordinary phosphoric acid (H3PO4), often called
orthophosphoric, is a syrupy liquid, of strong acid
properties; its salts are called orthophosphates (as
bone phosphate). It forms, with calcined zinc oxide
(and also with cupric oxide), a coherent, hard ce-
ment, used as a temporary tilling, or for strength-
ening frail walls in cavities of teeth.
As phosphoric acid is formulated from 3 mole-
cules of water, pyrophosphoric acid is formulated
from 2 molecules, and m(?^aphosphoric acid from 1
molecule of water, thus :
P2O5 -( 3II2O = 2II3PO4, phosphoric acid;
82 Inorganic Chemistry.
P2O5 -f 2H2O = H4P2O7, pyrophosphoric
acid;
P2O5 + H2O = 2HPO3, metaphosphoric acid.
The salts of the two latter are called pyrophos-
phates and metaphosphates, respectively. The
meta acid is also known as glacial phosphoric acid.
It is a vitreous solid, readily soluble in water; will
coagulate albumen, while the or^Ao variety will not.
By the addition of water and a gentle heat, the
glacial is converted into the ordinary so-called
ortho-phosphoric acid.
Phosphorus and hydrogen unite indirectly, pro-
ducing a compound phosphine (PH3), correspond-
ing with ammonia (I^Hg), a colorless gas of garlic-
like odor. It precipitates several metals from
solutions, as phosphides.
Phosphine is usually prepared by filling a flask
nearly full of an aqueous solution of caustic pot-
ash, to which are added a few bits of phosphorus.
The air above the solution in the flask should be
driven out by drops of ether or a current of illu-
minating gas.
4P + 3H2O + 3KH0 = 3KPH2O2 + PH3
Pot. Hydrate. Pot. Hypophosphite.
The PH3 is adulterated with traces of P2H4,
which, on escaping from the tube in the water pan
into the air, causes each bubble of the phosphine
Phosphorus. 83
to ignite with a brilliant flash, to form beautiful
ascending rings of smoke, consisting of the oxid-
ized phosphorus (P2O5).
There are two chlorides of phosphorus, the tri-
chloride (PCI 3) and pentachloride (PCI5). The
pentachloride is a solid substance, and is formed in
the experiment showing the spontaneous ignition
of phosphorus in chlorine gas.
84 Inorganic Chemistry.
CHAPTER XV.
CARBON.
Symbol, C. At. wt. 12. Sp. gr. 3-5, 2.15, 1-9.
Carbon is remarkable as existing in nature in
three distinct allotropic forms, which have no
physical properties in common, but whose chem-
ical nature is the same. These three forms are
known as the diamond, graphite^ and charcoal.
Twelve (12) parts, by weight, of either of these
varieties, united with oxygen, give us forty-foiu^
parts, by weight of the same compound (CO2).
Carbon also occurs extensively in nature, as in
the carbonates, of which limestone, marble, chalk,
and dolomite are examples. It is the characteristic
element of animal and vegetable life — all organized
tissues contain it — hence organic chemistry treats
only of carbon in its relations to other elements.
The DIAMOND occurs in nature in crystals, more
or less perfect, derived from the regular octa-
hedron. It is the hardest substance known, and
when cut and polished possesses high refractive
and dispersive power hence its use as a costly
gem. When diamond is heated in a gas incapable
Carbon. 85
of acting chemically upon it, it swells into a black
porous mass resembling coke.
Graphite, or plumbago, also known as black
lead, occurs in hexagonal plates, found as an ir-
regular vein traversing ancient slate beds. It is
also obtained in brilliant scales from melted cast-
iron, on cooling. Graphite has a semi-metallic
appearance, an unctuous feel, leaves a mark when
drawn on paper, is a fairly good conductor of heat
and electricity (which the diamond is not), and is
used in the making of lead-pencils (therefore
graphite), stove polish, crucibles, in electrotyping,
and as a varnish for grains of gunpowder.
An impure, quasi graphite, gas carbon, formed
in the retorts in manufacturing coal gas, is used in
galvanic batteries, and for the carbon points of the
arc electric light.
Charcoal includes all those varieties of coal
found in nature, ordinary charcoal (of either ani-
mal or vegetable origin), coke, and lampblack.
Coal consists of the remains of vegetable matter
that once flourished on the earth's surface, and
was subjected to a process of partial combustion,
much like that by which common charcoal is pre-
pared ; but much of the volatile principles yet re-
main, made up largely of hydrogen. Cannel and
soft coal contain the most hydrogen, and anthracite
86 Inorganic Chemistry.
the least. The elements, oxygen, sulphur, and
nitrogen, are also found in coal, in varying pro-
portions; and likewise earthy substances, which
form the ash.
The varieties recognized merely as charcoal are
produced by imperfect combustion of wood, bones,
etc. Nearly all the volatile principles of the orig-
inal substance are driven out, leaving a porous
matrix. The ability of charcoal to absorb certain
gases is due to this porosity. ^N'oxious gases, such
as ammonia and sulphuretted hydrogen, are ab-
sorbed in large quantity by freshly prepared char-
coal, which are condensed within its pores and
oxidized into harmless compounds by the oxygen
which it also absorbs at the same time. In this
way charcoal acts as a disinfectant.
Coke is the residue left in the retorts of the gas-
works from the destructive distillation of coal.
Lampblack^ considered as the purest variety of
amorphous carbon, is prepared by burning resin,
tar, petroleum, or turpentine, in a limited supply
of air, and collecting the smoke in suitable cham-
bers, by which the soot, carbon, is deposited.
Printer's ink, India ink, and black paint, are made
from lampblack.
Combustion. — In the wide sense of the term,
combustion means any chemical action that devel-
Carbon. 87
opes heat and light. Ordinarily, however, the
meaning is restricted to the burning of substances
in the air or in oxygen, and still further restricted
by the understanding that the elements of the
burning body are mainly carbon and hydrogen.
This fact obtains in the burning of coal, or wood,
or candle, or coal oil, or illuminating gas; and the
chemical action, briefly stated, consists in the
union of these elements, C and H, with the 0 of
the air. Sufficient heat must be applied to start
the process, which then continues, under favorable
conditions, until the materials involved are com-
pletely oxidized. An equation will enable us to
understand fully, the general reaction :
C -f H2 + 30 = H2O 4- CO2
Water. Carbon Dioxide.
Common combustion may therefore be defined
as " consisting of the union of the elements of the
burning body with the oxygen of the air, resulting
in the formation of water and carbonic acid gas."
The earthy constituents of the wood or coal, such
as potassium, are also oxidized at the same time,
forming the " ash."
Illuminating gas, manufactured by destructive
distillation of bituminous coal, is a mixture of free
h^^drogen, methane, ethene, ethine, and traces of
CO, CO2, N, and II2S.
Methane, marsh gas, or light carburetted hydro-
88 Inorganic Chemistry,
gen, CH4, is the lightest body known next to hydro-
gen, its specific gravity being 0.5576. It occurs free
in nature, being produced by decomposition of veg-
etable matter confined under water, and may be col-
lected by filling a wide-mouthed bottle with water
and holding it over the bubbles which rise on stir-
ring with a stick the mud at the bottom of marshy
ponds — hence its name, " marsh gas." It is also
the " fire damp " of the miners.
It is usually prepared in the laboratory by heat-
ing sodium acetate and sodium hydrate.
1^2iQ^11^0^ + :N'aHO = 1^2i^C0^ + CH4
Sodium Sodium Sodium Methane.
Acetate. Hydrate. Carbonate.
Methane is a colorless, odorless and tasteless gas,
and burns in the air with a faintly luminous flame.
Ethene, ethylene, heavy carburetted hydrogen
(^2^4); produced in the decomposition of many
organic bodies, is prepared by heating alcohol with
strong sulphuric acid, which abstracts the ele-
ments of water, thus :
CJI.O - H,0 = C,H,
Alcohol. Ethene.
Ethene is a colorless gas, much heavier than me-
thane, its specific gravity being 0.978; it burns
with a splendid white flame, and will unite with
chlorine (C2H3CI) forming an oily liquid of ethereal
odor, whence the name sometimes applied, '' oli-
fiant gas."
Carbon.
89
The reader will kindly appreciate the fact, that
these two gases, CH^ and C2 H^, are fair examples
of the hydrocarbons that take active part with the
oxygen of the air, in the process of ordinary com-
bustion ; and that the products are, necessarily,
water, (H2O), and carbonic acid gas, or carbon -
dioxide (CO2).
The light from burning oil, or candle, or illumin-
ating gas, or at the cheerful fireside, or the open
grate, holding either wood or coal, or natural or
artificial gas, consists substantially of the same
chemical reaction, i. e., the union of hydrogen and
carbon with atniospheric oxygen.
A jlame^ therefore, will vary in physical and
chemical properties, according to the relative quan-
tities of either the less or more dense hydrocarbon
compounds, and the oxygen involved in the pro-
cess. When the more dense or heavy gases burn
in the air, the light evolved is superior to that
given ofl[* by the less dense hydrocarbons, owing to
the difierence, in afiinity, between the carbon and
hydrogen of the burning gases, and oxygen.
Burning gases, containing relatively much hy-
drogen, give oflT greater heat, while those that are
relatively rich in carbon are deficient in heating, but
correspondingly rich in lighting power.
The common, everyday hydrocarbon flame, is
8
90 Inorganic Chemistry.
divided, for convenience of description, into three
parts :
1st. That which surrounds the wick of oil, or
candle, or jet of gas burner, the zone of noncom-
bustion.
2d. The zone of incomplete combustion, where hy-
drogen mainly oxidizes, and where the particles of
free Carbon are brought to a high state of incan-
descence, by the heat developed by the burning hy-
drogen, radiate their light — the luminous portion
of ;the flame — and
3d. The area of so-called complete combustion,
where carbon, with any remaining hydrogen, is also
oxidized.
Active chemical union between the burning
gases and the supporting oxygen of the air, takes
place mainly on the surface of the resulting flame,
the interior being hollow; such physical condition
is due to the fact that the oxygen of the air is ex-
hausted at the immediate surface, and is tlierefore
unable to penetrate the interior of the flame ; but
if the air (oxygen) be admitted to, and mixed with,
the combustible gases, before ignition, as in the
Bunsen burner, the extra oxygen, thus supplied,
supports the simultaneous combustion throughout
the flame, of both the carbon and hydrogen. Such
Carbon. 91
a flame is lacking in brilliancy, but possesses great
lieating power.
The same principles apply to the mouth blow-
pipe flame. Air (oxygen), is blown by the cheeks,
into the interior of the flame, wdiich resolves the
latter into two chief parts : a bluish inner cone and
an outer cone. The outer cone is named the oxi-
dizing area, because certain metals, when heated in
it, become oxidized. The apex of the inner cone
is possessed of great heating power, and is called
the reducing portion of the flame, because certain
metallic oxides, when heated at that point, are re-
duced to free metal and free oxygen. A little
practice with the blow-pipe, under proper instruc-
tions, will enable the dental student to easily solder
pieces of brass or copper, these metals being good
substitutes for silver and gold in experimental
practice.
The heat of combustion, ordinary or special,
is measured in heat units ; one unit being the quan-
tity of heat needed to raise one gram of water
from 0° to 1°. Hydrogen burning in oxygen,
furnishes 34,462 heat units, and carbon oxidizing,
8,080 units; that is to say, 1 grain of hydrogen, or
of carbon respectively, in burning in oxygen, would
raise the temperature of 34,462, or 8,080 grams of
water from 0° to 1°.
92 Inorganic Chemistry.
CHAPTER XVI.,
CARBON— Continued.
Cakbon DioxiDE.-Carbon and oxygen form two
compounds, the monoxide (CO), and the dioxide
(CO ) The latter compound is also known as car-
bonic acid gas. It is a substance of frequent oc-
currence and wide distribution, being a product ot
ordinary combustion, and fermentation, and putn-
cation of vegetable and animal tissues. From the
bodies of living animals it is exhaled by means ot
the lungs, in respiration. It is usually set free,
when carbonates are decomposed, and is the im-
portant constituent of the atmosphere, which sup-
plies carbon to the vegetable kingdom.
Carbon dioxide is prepared for experimental
purposes, or for producing, under pressure, the
effervescence in soda roatcr, by reaction between a
carbonate and a dilute acid, usually hydrochloric
or sulphuric, as the following equation will show :
n po + H SO, = CaSO^ + H^O + CO,
CaCO, + ^iXavtc calcium* Water. Carbm,
SSte. iclS""™ Su.p.ate. B.ox .
Carbon dioxide is a colorless, odorless gas, and
possesses a slightly acid taste. It is one-and-a-
half times as heavy as air, and twenty-two times
Carbon. 93
as heavy as hydrogen. It dissolves somewhat in
water at the ordinary pressure and temperature of
the air, but as the volume of a gas is inversely
as the pressure, great quantities of COg can he
confined in w^ater under pressure, as is seen iu
soda water, certain mineral waters, sparkling
wnnes, and beer, which, on exposure to the air,
rapidly lose their excess of CO2, and thereby soon
become flat and insipid.
Carbon dioxide interferes with combustion by
superseding the supporting oxygen, as is noticed
in the action of the '' Babcock Extinguisher."
Animal respiration is also affected by the pres-
ence of an abnormal quantity of carbon dioxide,
although it is not of itself a poison; it simply
acts like w^ater, or nitrogen, by preventing the due
aeration of the blood; it often accumulates at
the bottom of old wells, brewery vats, etc., and in
such places its presence may be detected by lower-
ing a lighted candle, which, if extinguished, will
indicate an atmosphere dangerous to animal life.
It is the choke-damp of the miners.
Carbonic acid is formed by the union of water
and carbon dioxide under pressure.
H2O -f- CO2 = II2CO3
Carbonic Acid.
This acid does not exist as a commercial sub-
stance, like nitric, or other acids, because on re-
94 Inorganic Chemistry.
moval of pressure, it decomposes into water and
carbon dioxide.
H2CO3 = H,0 + CO,
Carbonic Acid.
The salts of this acid, known as carbonates, are
easily disrupted by heat, as well as by even, weak
acids. Calcium carbonate, in the form of lime-
stone, marble, chalk, oyster shells, etc., when
heated, yield lime and carbon dioxide.
CaCOg + Heat = CaO + CO2
Calcium Lime
Carbonate.
Carbon monoxide (CO), known also as carbonyl,
and too frequently as carbonic oxide, is a combus-
tible gas, odorless, colorless, and tasteless, and
actively poisonous ; one per cent in the atmosphere
is considered dangerous. It may be prepared by
various methods, but it is probably never produced
synthetically. Some of the carbon dioxide formed
during combustion, when arriving at the surface of
the heated coal, suffers reduction (CO2 + C = 2C0),
at which point the resulting CO, meeting with at-
mospheric oxygen, unites with the latter, burning
with ablue flame, andproducingC02. CO-j-O^COg.
Where the combustion is confined, as in certain
anthracite stoves and furnaces, a portion of the
CO may escape oxidation, and pass through the
heated cast-iron to the surrounding air, causing
serious annoyance to the occupants of the room.
Carbon. 95
Cigarette smokers are probably injured more by
inhaling carbon monoxide (CO) than by any other
cause connected with the habit. This gas is
formed at the heated end of the burning cigarette,
and which, when inhaled, enters the circulation
and induces destructive chemical changes in the
blood.
Carbon disulphide (CS2) is formed synthetically
by passing a stream of sulphur vapor over red-hot
charcoal. The commercial carbon disulphide has
an exceedingly nauseous odor, but, if pure, the
odor is rather pleasant, suggestive of ether. It is
a clear liquid, of specific gravity, 1.29. Its vapor
Hiixed with air is explosive, and the compound
itself is very combustible, yielding carbon dioxide
and sulphur dioxide, CS2 + 60 = CO2 + 2SO2.
Carbon disulphide owes its importance to its
solvent properties. It easily dissolves such sub-
stances as caoutchouc, phosphorus, sulphur, oils, and
fats, and is used largely for extracting oils from
seeds and fats from animal refuse, and in the vul-
canization of rubber.
With N, carbon forms one compound named cy-
anogen (CX), to be described under "Organic
Chemistry."
96 Inorganic Chemistry,
CHAPTER XVII.
BORON.
Symbol, B. Sp. gr. 2.68.
Boron is a constituent of many minerals. It
may be obtained in two modifications. The first
is a soft, dark brown powder, analogous to
amorphous carbon, slightly soluble in water, and
fusible in the oxy-hydrogen flame. The second
variety is obtained in quadratic octahedral crystals,
varying in color from yellow to garnet red; in-
fusible, and nearly as hard and as highly refractive
as the diamond.
Boric oxide, B2O3, is formed whenever boron
is burned in the air or oxygen. United with
3 molecules of water, it forms boric (ortho-boric)
acid,
B2O3 + 3H2O =: 2H3BO3.
Boric Acid.
Boric Acid. — Boric acid is usually obtained from
solution of borax, in boiling water, by sulphuric
acid. Occurs in white crystalline scales, soluble in
water and alcohol, and possesses antiseptic prop-
erties.
Boron unites with H to form a o^aseous com-
Silicon. 97
pound, BII3, resembling NH3 and PH3. With F
it forms a colorless gas, and with CI a volatile
liquid ; but by far the most important compound
of boron is borax (Xa2 0 (6203)2, which will be
considered in connection with sodium.
SILICON.
Symbol, At. Wt. Sp. Gr.
Si. 28. 2.49.
Inasmuch as we began the study of the non-
metallic elements with oxygen, it is meet that we
conclude the subject with the next most abundant
ingredient of the earth's surface, namely, silicon,
sometimes called silicium. It is obtained by heat-
ing together metallic potassium and potassium sili-
cofluoride, 4K + l^^^'^"^^ = 6KF + Si.
Like carbon, silicon may be obtained in three
different modifications. One is an amorphous
dark brown powder. The second consists of hex-
agonal plates resembling graphite, and the third
variety crystallizes in octohedrons of exceeding
hardness. It fuses only at very high temperatures,
and is insoluble in all acids, except hydrofluoric.
The isolated element has no practical importance.
Silicon combined with oxygen, and also with
potassium, aluminum, and other metals, enters
largely into the structure of the solid crust of the
earth.
9
98 Inorganic Chemistry.
The oxide of silicon (SO 2), known as silica, and
when in powder, as silex, is the principal earthy
material of our planet, occurring more or less pure
in sandstone, quartz, or rock crystal, amythyst,
agate, cornelian, chalcedony, and the beautiful opal.
In combination with certain metallic oxides, it
forms a class of salts called silicates, of which by
far the largest variety of minerals consist. Sili-
con oxide is found in animal tissues ; it stiffens the
stems of the various grasses and growing grains,
and is also found dissolved in the waters of many
thermal springs. It has a specific gravity of 2.6.
The natural crystal is sufficiently hard to scratch
glass ; it is but slightly soluble in water, and is un-
affected by acids, except hydrofluoric.
Si02 is an acid oxide. When sand is fused with
sodium or potassium carbonate, a reaction ensues
by which a silicate of these metals is formed.
Si02 + Na2C03 = Na2Si02 + CO2.
Sodium Silicate.
The silicates of sodium and potassium are known
as ID ater glass. They are soluble in water, but the
silicates of the other metals are in general, insolu-
ble. Porcelain and glass are artificial mixtures of
silicates. Porcelain (artificial) teeth, consist of
aluminum silicate and the double silicate of alum-
inum and potassium. Window glass is a silicate
of calcium and sodium. Bohemian glass. is a sili-
Silicon. 99
cate of calcium and potassium. Crystal or flint
glass, is a silicate of potassium and lead.
Silicon unites with hydrogen to form a colorless
gas, SiH^, analogous to CH^. It unites with
chlorine, bromine, and iodine, SiCl^, SiBr4, 81X4,
corresponding to carbon chloride, bromide, and io-
dide It also forms a chloroform, SiHClg, similar
in some respects to ordinary chloroform, CHCI3.
Indeed, although silicon and carbon are appar-
ently widely separated in nature, being the char-
acteristic elements of the mineral and organic
kingdoms respectively, they are very near akin
in their chemical naturCi.
If a strong solution of sodium or potassium sili-
cate be acted on by hydrochloric acid, a jelly-like
substance will separate out. This substance is
known as or^Ao-silicic acid, H^SiO^. By losing a
molecule of water it becomes meta-sWicic acid,
1128103. If the mixture of hydrochloric acid and
water glass be sufficiently dilute, no separation of
the silicic acid will take place. A separation, how-
ever, can be beautifully and instructively accom-
plished by dialysis. The dializcr, consisting of a
taut membrane of bladder or skin parchment,
placed in the solution, whereby the sodium or po-
tassium chloride will diffuse through the membrane,
leaving a clear, tasteless solution of silicic acid.
100 Inorganic Chemistry.
which in time solidifies to a jellj. Crystallizable
bodies like salt, sugar, etc., diffuse readily through
the dializer, while non-crystallizable bodies, like
jellies, glue, albumen, etc., do not pass at all.
These two classes are termed respectively crystal-
loids and colloids.
PAR.T SECOND.
INORGANIC CHEMISTRY.
CHAPTER I.
CHEMICAL PHILOSOPHY— i^e'SMw^d.
Now that we are acquainted with some of the
chemical and physical properties belonging to a
few of the elementary forms of matter, we will be
better enabled to understand more clearly the fol-
lowing additional facts in chemical philosophy.
The atomic theory of Dalton, which assumes
that matter is made up of ultimate particles, called
atoms, clearly explains the known laws of chemical
reactions. As atoms are individually indivisible,
whole atoms, or multiples of them, must be in-
volved in chemical union. A chemical compound
is definite in its nature, i. e., each of its molecules,
of which the mass is composed, must contain the
same kind and number of atoms, similarly ar-
ranged.
We do not know the real weight of atoms, but
as hydrogen is the lightest body, and therefore
taken as unity, the comparative weights of the
atoms of the several elements can be ascertained.
(101)
102 Inorganic Chemistry.
The real weights of the atoms of the several ele-
ments are fixed and unchangeable for each; it fol-
lows that molecules, each containing the same
kind and number of atoms, producing a given
compound, must be alike in weight. Equal
weights of water, under equal conditions, will con-
tain the same number of molecules; hence the
116
molecular formula, H2O, not only truly represents
the relative quantities of H and 0, but also the
comparative weight of a given quantity of water.
The molecular weight is the sum of the atomic
weights. The molecular weight of water is there-
32 16
fore 18; that of SO3 is 80; these two substances
combine with each other in the above proportions
to form a molecule of H2SO4, whose weight is the
sum of 18 + 80 r= 98.
Aside from the known relative weights, or mul-
tiples of them, in which the elements unite with
or displace each other, there are other relations
between the accepted atomic weights, and certain
physical phenomena, which prove the correctness
of the former.
The remarkable relation between the atomic
weights of the elements, and their capacity for
heat, called specific heat, or atomic heat, is ex-
pressed by the statement that the products of the
specific heats of the elements into their atomic weights,
Chemical Philosophy. 103
give a nearly constant quantity, the mean value being
6.4. The slight variations noticed are no doubt
due to unavoidable errors in experiment. In other
words, all atoms have equal capacities for heat; the
same amount of heat that will raise 1 part by
weight of hydrogen one degree, will raise 7 parts
by weight of lithium, 16 of oxygen, 23 of sodium,
56 of iron, 108 of silver, 197 of gold, etc., one
deo^ree.
In many cases, the molecules of compounds
which crystallize in like form, called isomorphous,
are supposed to contain an equal number of atoms ;
thus, certain sulphates are isomorphous with cor-
responding selenates ; sesquioxide of iron, Fe203,
is isomorphous with sesquioxide of aluminum,
AI2O3 ; and in case of doubt as to the correct
atomic weight of an element, as for instance of
aluminum, this relation is appealed to.
All molecules, according to the law of Ampere,
have the same size; that is, all molecules, when in
the gaseous state, under equal conditions of heat
and pressure, occupy the same volume, or same
amount of space. The composition of gaseous
elementary molecules can therefore be expressed
in volumes, as well as in atoms. The molecule of
hydrogen is assumed to contain 2 volumes, or 2
atoms, of hydrogen, IIII ; the molecular weight of
104 Inorganic Cheynistry.
hydrogen is therefore 2, twice that of a single atom
of hydrogen ; and as this element is taken as
unity, its density is one-half its molecular weio-ht
or its molecular volume is equal to 2 atoynic vol-
umes. Those elementary gases or vapors whose
molecules are supposed to contain 2 volumes, or 2
atoms, have a density, referred to hydroo-en as
unity, equal to one-half their molecular weights,
or identical with their atomic weights.
DENSITY. DENSITY.
Hydrogen 1 Sulphur 32
Oxygen 16 Bromine 80
Chlorine 35.5 Iodine 127
Since the molecular weight represents the
weight of two volumes, as II— H, 0=iO, and
density represents the weight of one volume, the
density of any homogeneous vapor, either element-
ary or compound, is one-half its molecular weight.
Ordinary oxygen, whose molecular formula is
0=0, has a molecular weight of 16 -f 16 =r 32 ;
its density is one-half of 32, or 16. Ozone /^\
' O 0
has a molecular weight of 48; its density is 24.
Carbon dioxide, whose formula is CO2, has a
molecular weight of 12 -f 32, or 41; its density is
44 -f- 2, or 22. Conversely by knowing the dens-
ity, the molecular weight can be obtained by mul-
tiplying by 2.
Chemical Philosophy. 105
It is also noticed that the gaseous product of the
union of two elementary gases, when combining in
equal volumes, retains tlie original volume of its
constituents; as 1 vol of H and 1 vol. of CI form
2 vols, of HCl. When 3 or more vols, of combin-
ing gases, elementary or compound, enter into
combination, condensation takes place to 2 vol-
umes, as
2 vols, of H and 1 vol. of 0 form 2 vols. H2O ;
1 vol. of ethyl CH5 and 1 vol. of CI form 2 vols.
CH5CI;
2 vols, of ethyl (CH5)2 and 1 vol. of 0 form 2
vols. (CIl5)20.
Hence the law of Avogadro: The molecules of all
gases, simple or compound, occupy equal volumes ; or
equal volumes of all gases contain equal numbers of
molecules. The molecular formula of compound
gases (or vapors), and the atomic weights of the
elements contained in them, can, by noting the
vapor density, be determined by this law.
Equivalency. — Certain elements unite with each
other in only one proportion ; they form, with each
other, but one compound. Their atoms have only
one point of attraction ; their atomicity or valency
IS one. These elements are called monogenic or
monads, signifying one. The other elements are
called polygenic. The atoms of the monad ele-
106 Inorganic Chemistry.
merits are equivalent to each other; the atoms of
the polygenic elements are equal in combining, or
substituting power, to two or more atoms of the
monads. One atom or volume of H, and one atom
or volume of CI unite; they form but one com-
pound, HCl ; they are both monads. One atom of
Na will displace H and take up with the CI :
HCl + Na =r NaCl + H.
The valency of ^N'a is, therefore, the same as H
and CI ; it is monogenic. The atom of 0, how-
ever, is equal in combining power to two atoms of
H, Na, or any other monad; oxygen, therefore, is
a dyad element. One atom of 0 and two atoms of
H unite (H2O). One atom of Na will drive out
one atom of the hydrogen and take its place; the
one atom of oxygen being able to attract and hold
together the two unlike atoms in a homogeneous
molecule :
H2O + Na =: H^aO 4- H.
One atom of Zn (65 parts by weight) requires
two molecules (73 parts by weight) of HCl to sat-
isfy its combining power:
Zn -f 2HC1 = ZnCl2 + 2H.
Zinc, accordingly, is a dyad. When zinc is oxid-
ized, the molecule produced contains one atom
each of dyad zinc and dyad oxygen:
Zn + 0 = ZnO.
I
Chemical Philosophy. 107
This difference in the number of points of at-
traction or saturating power belonging to each
atom of the various elements is often denoted by
placing Roman numerals, or dashes above or to the
right of the symbols, as —
Univalent elements, or monads, as H'
Bivalent elements, or dyads, as.. ,0"
Trivalent elements, or triads, as Au'"
Quadrivalent elements, or tetrads, as...C'^
Quinquivalent elements, or pentads, as..P^
Sexvalent elements, or hexads, as Cv"^
Elements of even equivalency, namely, the dyads,
tetrads, and hexads, are classed under the general
term artiads^ signifying even; and those of uneven
equivalency, the monads, triads, and pentads, are
called perissadsy which means uneven.
108 Inorganic Chemist?^,
CHAPTER 11.
GRAPHIC FORMULA.
Formulae are sometimes written graphically, that
is, a number of lines or bonds, connecting the sym-
bols, indicating the equivalency of each; thus:
Hydrochloric acid, HCl H CI
Water, H2O H— 0— H
Carbon dioxide, CO2 0— C— 0
CI
Am. Chloride, NH.Cl "^^iIt-^"^
' H^ \H
0
Nitric Acid, HNO3 N 0— H
II
0
0 0
Zinc Nitrate, Zn(N03)2 N— 0— Zn— 0— N
A II
0 0
These graphic formulae are often abridged by the
use of dots only, tlius :
H.Cl H.O.H 0..C..0
By observing the above diagrams, it will be no-
ticed that the units of attraction belonging to each
atom are satisfied by union with those of other
Chemical Philosophy. 109
atoms. And, accordingly, it is found that in all
saturated molecules, the sum of the perissad atoms is
always even. A molecule may contain 2, 4, or 6,
etc., monad atoms, as in PICl, H2O, CH^, C2Hg,
etc.; or 1 triad atom, as Au'", and 3 monads, as in
AuClg ; or 1 pentad and 5 monads, as in l^H^Cl;
but never an uneven number of perissad atoms.
This is the law of even numbers.
For the same reason the molecules of the peris-
sad elements consist of an even number of atoms.
The molecule of hydrogen contains two atoms
H — 11. So also the molecule 'of chlorine CI — CI;
the molecule of phosphorus contains four atoms,
P^P As=As
II II So also the molecule of arsenic, 11 11
r=P. As=As
The molecules of dyad elements, however, may
contain either an even or an uneven number of
atoms, as will be observed on again submitting the
following :
.A,
Ordinary oxygen. Ozone.
The true equivalency of an element may be ex-
pressed as that which represents the maxim,um number
of monads atoms, with which one atom of it can com-
bine. The molecule, ammonium chloride, NH4CI,
shows one atom of IST saturated by five monad
110 Inorganic Chemistry.
atoms; no other atom or atoms can unite with the
above group. Accordingly nitrogen is a pentad,
i, e., its atom is equal to five monad atoms. One
atom of dyad oxygen can take up with no more
than two atoms of monad hydrogen H2O''.
When variation in the valency of any element
occurs, it always takes place by 2 units. So that
an element may appear as a monad in one com-
pound, a triad in another, and a pentad in still an-
other; or an element may act as a dyad in one case,
or a tetrad in another, and a hexad in another. For
instance, nitrogen appears to be a monad in nitrous
oxide ^2^? ^ triad in ammonia NH3, and a pentad
in ammonium chloride NH^Cl; sulphur is a dyad
in dihydrogen sulphide HgS, a tetrad in sulphurous
oxide SO2, and a hexad in sulphuric oxide SO3.
In compounds where the full valency of the ele-
ment is not exhibited, as in NH3, ammonia, the
two units belonging to I^ uncombined, probably
unite with each other, for the time being; but the
molecule of ammonia is willing to unite directly
with HCl, forming NH4CI, wherein the full va-
lency of K" is satisfied. Tetrad sulphur in SOg can
be oxidized into SO3, becoming thereby a hexad.
A perissad element is alwa3^s a perissad; an
artiad element, always an artiad, inasmuch as vari-
Chemical Philosophy, 111
ation in valency of either class, when it does occur,
is always by 2 units.
The statement that the true valency of an ele-
ment is determined by the composition of its hy-
drides, chlorides, etc., rather than by its oxides,
etc., will be appreciated if we consider the part
dyad atoms play in combination. For example,
dyad 0" can enter the saturated molecule of water
II — 0 II without disturbing the existing atomic
value of hydrogen, thus H — 0 — 0 — H, because any
dyad atom (or radical), introduces one unit of
equivalency into the compound which it enters,
and neutralizes another, leaving the valencies the
same as before. Potassium is a monad, because
one atom of it unites with only one atom of chlo-
rine, K — CI, and in no other proportion ; but in ad-
dition to its corresponding oxide, K — 0 — K, there
is a tetroxide of potassium K — 0 — 0 — 0 — 0 — K,
wherein the valency of the K' is seen to be the
same as in its normal oxide. Any other dyad atom
(or radical) can act in the same way.
When two or more atoms of a polygenic element
are present in the same molecule, the element in
question may seem to possess less than its normal
valency. Carbon is a tetrad inasmuch as four
atoms of hydrogen or other monad, are as many as
one atom of carbon can saturate, (CH^); there are,
112 Inorganic Chemistry.
however, a great many other compounds of C and
H alone, whose molecules contain more than one
atom of carbon, and where the C appears to pos-
sess an atomicity of less than four. This is owing
to the units of valency, belonging to the carbon
atoms, not saturated by the hydrogen (or in other
cases by atoms of other elements), uniting with,
and so satisfying each other. One or two examples
will suffice :
In methane, CH^, carbon is a tetrad ; in ethane,
CgHg, carbon appears to be triad; in ethene,
C2H4, it appears to be a dyad, and in ethine,
C2H2, a monad. The following diagrams will
readily explain the apparent discrepancy:
H H
I I
H— C— H H— C— H H— C— H C— H
I I II III
H H— C— H H— C— H C— H
k
Methane, Ethane, Ethene, Ethine.
The same faculty, ot mutual combination of
otherwise free units, is possessed by the atoms of
other polygenic elements, but not in as high a de-
gree as with those of carbon.
Radicals. — Radicals may be defined as residues,
obtained by removal of one atom or more from a
saturated molecule. There are elementary and
Chemical Philosophy. ■ 113
also compound radicals. A perissad atom, as an
atom of hydrogen, H, is an elementary radical, and
probably never exists free ; such atoms, when set
free from combination, unite either with each other
or with atoms of another kind to form again satu-
rated molecules. A mass of hydrogen, for instance,
does not consist of an aggregation of uncombined
atoms, H, H, H, H, H, but of a great number of
molecules, each containing two atoms, chemically
united, H — H. Suppose a molecule of hydrogen,
H — H, be acted on by a molecule of chlorine,
CI — CI, the reaction would be as follows :
H— H + CI— CI = 2HC1
The two atoms (radicals) of the hydrogen mole-
cule, and the two atoms (radicals) of the chlorine
molecule, would become separated by the influence
of the superior chemical attraction between the
unlike atoms (radicals), and recombination take
place, resulting in the production of two mole-
cules of hydrogen chloride, as seen in the equation.
Again suppose, these latter two molecules, 2HC1,
be brought under the influence of a molecule of
sodium (l!^a — Na), another change would occur,
2IIC1 -f Na— Na = 2XaCl -f H— II. The 2C1 rad-
icals would leave the hydrogen and take up with
the 2 Na atoms (radicals), forming 2 molecules of
sodium chloride, letting the 211 atoms go free,
10
11-4 Organic Chemistry.
which, in the absence of more attractive radicals
of some other kind of matter, would be satisfied
to unite with each other, and give birth again to
a molecule of hydrogen.
Compound radicals are unsatisfied groups of two
or more unlike atoms, and have a valency corre-
sponding to the number of equivalent units removed
from a saturated molecule. H — 0 — H (water),
is a saturated molecule; if one of the hydrogen
atoms be removed, the resulting group, — 0 — H
(hydroxyl), will evidently have the same combin-
ing power as the divorced atom of hydrogen (H — ).
Hydroxyl is, therefore, a univalent (monad) com-
pound radical, having one free bond. It exists in
all the hydrates and in many other compounds.
Sodium thrown on water removes an equivalent
quantity of hydrogen, and takes its place, in union
with the resulting hydroxyl :
[N-a— N"a + 2H-0— H = H— H + 2]^a— 0— H
Sodium Hydrate.
The names of compound radicals of uneven
valency (monads, triads, etc.) end in yl; they do
not exist free, but the instant of their development,
if unaffected by radicals of another kind, they
tend, like perissad atoms, to combine among them-
selves. Free hydroxyl is not known, but a com-
pound whose molecules are made up of 2 hydroxyl
groups, H — 0 — 0 — H, is a well known substance.
Chemical Philosophy. 115
Compouuds in general are often formulated so as
to show their molecular constitution by radicals.
Thus, nitric acid, HNO3, may be considered as con-
O
II
sisting of the 2 radicals, H— 0— and IST = HO.NO2.
II
O
Water is analogous in formula to sodium hydrate,
H.OH Xa.OII. The graphic formula of phosphoric
Water. Sodium hydrate.
0— H
acid is 0 = P— 0— H
^0-H, etc.
An understanding of the part played by radicals
in the carbon compounds included in organic
chemistry, is most important, and their relations
may be somewhat studied in this connection to
advantage.
The atom of carbon has four points of attraction ;
it can not, therefore, take up more than four atoms
of hydrogen, or other monad radical. Methane,
C'^'H^, is the typical saturated hydro-carbon. If
one of the four atoms of hydrogen be removed,
the residue will, of course, be O^'H'g, named methyl^
which has the same valency as the atom of hydro-
gen, or one unit, capable of uniting with one atom
of chlorine, for instance, to form methyl chloride,
CH'3C1. Two atoms of hydrogen removed from
116 Inorganic Chemistry.
methane, CH^, leaves the dyad radical methene,
CW ^^ able to take up two atoms of chlorine to
form methene chloride, CH''2^^2- I'h^ee atoms of
hydrogen removed from methane, results in the
trivalent radical methenyl, CH'^', which in union
with three atoms of chlorine, produces methenyl
chloride, CHCI3 (chloroform), and if all four of the
hydrogen atoms in methane be driven out, the tet-
rad carbon atom remains to be saturated by four
atoms of chlorine, CCI4, or other monad element,
or by two dyad radicals, or by one triad and one
monad radical, — C — .
I
Allusion has been made to the non-interference
of dyad atoms, or radicals, with the equivalent
values of the atoms or radicals, in those saturated
molecules which they may enter.
H
I
The dyad compound radical, methene, — C —
J,
like an atom of oxygen — O — , can evidently join
itself to an already satisfied molecule, because it
is able to neutralize one unit of valency in the
compound it enters, and introduce another, as may
be understood by the following diagram :
Chemical Philosophy. ^ 117
H
H H-C— H
CH4 or H-C— H -f H— C— H= H— C— H or Q^B.^
I I I
H H
Methane. Methene. Ethane.
Ethane, CgHg, is methane CH4, plus the dyad
radical CHg. If we presume to abstract one atom
of hydrogen from ethane, we will have the univa-
lent radical ethyl Q^W ^, capable of joining itself
to an atom of chlorine, as in ethyl chloride
C2H'5^C1, or to hydroxyl, as in alcohol, C2H'5'OH,
or two such groups, to — 0 — , as in common ether
(CH,),0.
Hydrogen is not the only element involved in
removal from saturated molecules, to form radicals.
Indeed it is only necessary to assume a number of
units of valency abstracted from any saturated
molecule, in order to obtain a radical of corre-
sponding combining power; and it is evident, from
their mode of derivation, that the number of com-
pound radicals which are capable of existence is
without limit. A great many of them are known
to individually enter into the formation of special
classes of compounds, like the salts of the same
metal, enabling us to comprehend clearly the rela-
tions that exist between vast numbers of organic
compounds, which otherwise would be impossible.
118 Inorganic Chemistry.
CHAPTER III.
MATERIA MEDICA.
Materia Medica is that part of therapeutics which
includes the study of the origin, physical and chemi-
cal nature, therapeutic and toxic effects, local and
general, of materials employed for the cure, allevia-
tion, or prevention of disease.
Although it is not often incumbent on the den-
tist to prescribe medicines for internal administra-
tion, it is proper that he should know the general
effects, dosage, incompatihles and antidotes, when
so exhibited, of those drugs he uses in his practice
as local agents, inasmuch as a large majority of
them are active poisons.
By knowing these facts he can make judicious
selection and combination of materials for any pre-
scription that, in his judgment, will best suit the
case in hand. He would not, for instance, order
a combination of any soluble chloride with silver
nitrate, or any vegetable astringent, with persalts
of iron; or use, even topically, excessive quantities
of arsenic, or tincture of aconite root, etc.
The art of writing decent prescriptions is a seri-
ous labor to the average student. If we could pre-
Materia 31edica. 119
vail upon him to discard in toto the signs and
symbols of the old system of weights and measures
and adopt the metric system exclusively, he would
find the task much easier; and if, as occasionally
happens, he be deficient in a knowledge of the
Latin language, he should take courage, and realize
tliat very few Latin phrases, or abbreviations, are
needed in prescribing, as the following sufficient
presentment of them will prove :
A; aa. Ana; of each.
Ad. add., Addendus ; to be added.
Ad lib.. Ad libitum ; at pleasure.
Alb., Albus ; white.
Aq., Aqua; water.
Aq. dest.. Aqua destillata; distilled water.
Chart., Charta; paper.
Dil., Dilutus; diluted.
F., Ft., Fiat; let a — be made.
Fl., Fluidus; liquid.
Fol., Folium; a leaf. Folia; leaves.
Gr., Granum; a grain. Grana; grains.
Gtt., Gutta; a drop : Guttse ; drops.
Ilyd., Hydro ; water.
Ilydr., Hydrargyrum; mercury.
Inf., Infnsum ; infusion.
M., Misce ; mix.
Mist., Mistura; a mixture.
120 Inorganic Chemistry.
No., Numero ; in number.
01., Oleum ; oil.
P., Pulvis; powder.
Ph., Pharmacopoeia.
Pil., Pilula; a pill ; pilulse, pills.'
Q. S., Quantum Sufficiat ; as much as is sufficient.
15^., Recipe; take.
Rad., Radix ; root.
Rect., Rectificatus ; rectified.
S., or Sig., Signa ; write.
Ss., Semis; half.
Solv., Solve ; dissolved.
Spr., Spiritus; spirit.
Tr., or Tinct., Tinctura; tincture.
U. S. P., United States Pharmacopoeia.
In writing a prescription containing a number
of substances, it is proper to place the most impor-
tant article in the combination, first, as the basis;
the adjuvans or assistant to the base, next; the cor-
rective^ if the two first have certain objectionable
properties, as taste or smell, comes next; and
finally the vehicle, to give form and elegance to the
whole. The following will serve as an example :
R. Acidi salicylici. Basi^.
Sodii bi boras, aa 1.00 Gm. (gr. xv), Assistant.
Spts. rect., 4.00 CC. (f^i), Corrective.
Aq. rosse q. s. ad 125.00 CC (f^iv), Vehicle,
M. S. Use as a general mouth wash.
Materia Medica. 121
Apothecaries' weights and measures.
Pound. Ounces. Drachms. Grains.
Lb. 1 = 12 = 96 5760
§i = 8 = 480
3i = 60
Fluid measure.
Pint
(Octarius).
F, Ounces.
F, Drachms.
Minims,
01
= 16
=
128
=
7680
ill
=
8
=
480
f3l
:;:z:
n 60
Metric System.
The meter is the basis of the metric system, and
is the standard unit of linear measurement of that
system.
The meter is the 10 millionth part of the distance
from the equator to the pole (the earth's quadrant) ;
it is about 10 per cent longer than the yard.
The unit of fluid measure is the liter — the cube
of y^^ meter (one decimeter), or 1,000 cubic centi-
meters; it is equal to about 32 fluid ounces.
The cubic centimeter (C.C.) is equal to about 15
minims.*
* Exactly 16.231 minims. Approximative comparison is suf-
ficient for our purpose.
11
122 Inorganic Chemistry.
The Gram is the metric unit of weighty and repre-
sents the weight of 1 cubic centimeter of water at
its maximum density (4° C— 39° F). The gram is
equal to about 15 grains. Fractions over 15 grains
and 15 minims, with reference to the gram, and to
the cubic centimeter, may be ignored.
We accordingly have :
1 Gram equal to 15 grains.
4 Grams equal to 1 drachm.
1 Drachm equal to 4 Grams.
1 Cubic centimeter equal to 15 minims.
4 Cubic centimeters equal to 1 fluidrachm.
1 Fluidrachm equal to 4 cubic centimeters.*
The term flaigram has been suggested as more
euphonious than cubic centimeter, but has not been
generally accepted. Inasmuch, however, as the
gram expresses the weight of 1 cubic centimeter
of water, the term fluigram is not inappropriate,
and will be used by us hereafter instead of cubic
centimeter : fluigram abbreviated f. Gm, and Cubic
centimeter CC, mean, therefore, the same measure
of any liquid.
Gram should be written with a capital " G," ab-
breviated Gm ; and in order to avoid mistaking
this sign for gr, which latter is always written
with a small " g," it is proper to place the Arabic
* Slightly changed from Oldberg.
Materia Medica. 123
numerals before the sign ; thus, 10.00 Gm (ten
Grams). Apothecaries' weights and measures (old
system) have their signs followed by Roman nu-
merals, thus, gr X (ten grains).
in writing prescriptions according to the metric
system, the only signs needed are the Gm and
fGm; and fractions of them are stated decimally,
in the same way we write our divisions of federal
money, thus:
10.00 Gm (ten grams), analogous to $10.00
(ten dollars) ; 0.05 Gm (five centigrams), analogous
to $0.05 (five cents).
If we regard the Gm or fGm, as corresponding
in this respect to our dollar, wq can appreciate the
relation most easily by the following comparison :
Gm $
1 .00— One Gram . 1 .00— One dollar.
.50 — Fifty centigrams. .50— Fifty cents.
.02— Two " .02— Two "
.001— One milligram. .001— One mill.
In speaking of the divisions of the gram, the
same terms may be employed that are used in
speaking of money matters. For instance, 0.10 Gm
= one dime; or 0.10 fGm = one fiuidime. The
fluidime may be considered the minimum quantity
for liquids, equal to IJ minims, and the mill, the
124 Inorganic Chemistry.
smallest representative of weight, equal to g^^ of a
grain. -^
The prefixes used in the metric system are
sometimes convenient in speaking of weights and
measures, but in prescribing the}^ need not be
written, the Arabic numerals being sufficiently ex-
plicit. As, for instance, with reference to any unit
in the metric system.
Myria means 10.000
Kilo '' 1.000
Hecto " 100
Deka " 10
Deci " 0.1
Centi " 0.01
Milli " 0.001
The following approximate equivalents are
mainly taken from Oldberg, and are sufficiently
accurate to answer all purposes of mere com-
parison :
Troy Grains (or Minims), Grams (or Fluigrams).
^5 0.001 (1 mill)
i 0.03 (3 cents)
1 0.06 (6 cents)
U 0.10 (10 cents)
10 0.65 (65 cents)
15 1.00 (1 Gram), (or fGm)
30 2.00 (2 Grams), (or fGm)
60(1 Drachm) (Fl drachm)) . .4.00 (4 Grams), (or fGm)
Materia Medica. 125
Troy Ounces (or Fluid Ounces). Grams (or Fluigrams).
1 30.00 (30 Gm or fGm)
4 120.00 (120 Gm or fGm)
With the foregoing preliminaries in materia
medica, more or less mastered, our hope is now to
study carefully the medicinal properties, in con-
nection with the chemical history of the various
metallic salts, and organic compounds, that may be
deemed worthy of notice.
We shall endeavor to systematize the study, by
tirst presenting their physiological and therapeutic
effects, if any, when applied locally ; then, when
taken internally, their influence on the brain and
nervous system generally; on the circulation,
respiration, temperature, and on the secretions ;
naming the principal diseased conditions in which
they are indicated; and, finally, their antidotes
and dosage, with an occasional prescription.
126 Inorganic Chemistry.
CHAPTER IV.
METALLIC ELEMENTS.
All those elements, studied in Part First, with
the exception of hydrogen, are classed as non-
metallic; those elements yet to be considered, with
the exception of arsenic, are classed as metallic.
Arsenic seems to be the connecting link between
the two classes.
A few of the metals, as gold and platinum, are
found in nature, in the metallic state ; the large
majority, however, are found united with non-
metallic elements, forming oxides, chlorides, car-
bonates, etc., wherein the metallic i)roperties are
masked, and which constitute the ores from which
the metals involved, are obtained.
Some of these elements, as gold, iron, copper,
etc., are most useful when in the metallic state ;
and others, as potassium, calcium, barium, etc.,
are most important when in combination with non-
metallic elements.
When metals unite with non-metals, true chem-
ical compounds are formed. When metals unite
among themselves (except with arsenic, and those
closely allied to it), the combination does not
Metallic Elements. 127
produce a true chemical compound, but an alloy^
wherein the metallic nature is preserved. Many
alloys are extremely useful, and exhibit desirable
properties not possessed by their individual con-
stituents ; gold is too soft for ordinary use, but if
alloyed with copper, or silver, or platinum, etc.,
becomes qualified for certain practical purposes.
Copper is too soft and tough to work in a lathe,
but if fused with one-half its weight of zinc, it
forms the hard, tenacious alloy, known as brass.
Copper and tin in different relative proportions
give us the useful alloys, bronze, bell metal, specu-
ulum metal, etc. German silver consists of 100
parts copper, 40 of nickel, and 16 of zinc. Type
metal is an alloy of antimony and lead. Alloys
of mercury with other metals are named am.algams.
The melting point of an alloy is generally lower
than the mean melting [)oint of its constituents.
For instance, tin melts at 235° (455 F.) ; bismuth,
melts at 2(34° (507 F.) ; lead melts at 320° (608 F.).
An alloy of 1 part of* tin, 2 of lead, and 2 of bis-
muth will melt as low as 93° C (200 F.). Such an
alloy is useful in attaching teeth, by dovetail, to
old celluloid and rubber plates, and maybe packed
in with a warm burnisher.
The metals differ greatly in specific gravity, rang-
ing from potassium, sodium and lithium, which are
128 Inorganic Chemistry.
lighter than water, to platinum, iridium and os-
mium, which are more than 21 times heavier than
water.
They differ also in tenacity^ or the power of re-
sisting tension. The order of tenacity among those
metals susce[)tible of being easily drawn into wire
is determined by observing the weights required to
break wires of the same size, and is as follows :
Iron, copper, platinum, silver, gold, zinc, tin, and
lead.
Malleability, or power of extension under the
hammer, or between the rollers of a flatting mill,
is possessed in a high degree by gold, silver, cop-
per, tin, platinum, lead, and iron.
The fusing points of metals vary greatly, ranging
from mercury, which melts at — 39°, to platinum,
which requires the heat of the oxy-hydrogen flame.
A certain uniformity of color is presented by the
metals, except copper, which is red, and gold, which
is yellow ; all the other metals (leaving out the
faintly pinkish tint of bismuth, and the yellowish
tinge of calcium and strontium), are included be-
tween the white of silver and the blui,sh gray of
lead.
The several metals are classified into groups, ac-
cording to certain chemical and physical proper-
ties possessed by them ; those of the same group
Metallic Elements. 129
generally, also, possess the same valency. Brief
allusion to some of the characteristics of two or
three groups will suffice. For example:
The metals of the alkalies., viz., K, IS'a, Hb, Cs,
and Li, are soft, easily melted, volatile at a higher
temperature, will decompose hot or cold water
through their love for oxygen. Their oxides are
strongly basic, and are very soluble in water, form-
ing exceedingly caustic and alkaline hydroxides
Their carbonates are soluble in water, and being
monads^ they each form only one chloride (K CI).
The metals of the alkaline earths^ Ca, Ba, and Sr,
form oxides less soluble in water than those of the
preceding group, but exhibiting, though in less de-
gree, similar basic, caustic and alkaline propor-
ties. Their carbonates are insoluble in water; they
each form but one chloride, which, as they are
dyads, is a dichloride (CaClg).
The metals of the earths, erbium, yttrium, didy-
mium, etc., form oxides that are not soluble in water.
The metals of this group occur only in a few rare
minerals.
All metals form binary compounds with chlo-
rine. The monochlorides and dichlorides of the
metals, excei)ting silver chloride (AgCl), and mer-
curous chloride (Hg2Cl2), are soluble in water.
Metallic chlorides unite with certain oxides, form-
130 Inorganic Chemistry.
ing oxyehloridfs, and with organic bases, also, such
as aniline and the ptomaines.
]!^early all metals unite with Br and I. Most
metallic bromides and iodides are soluble in water;
they closely resemble, in many instances, the cor-
responding chlorides.
Oxygen unites with all the metals, with many of
them in several proportions. Some metallic oxides,
as K2O and CaO, do not decompose by heat alone;
others, as AU2O3, Ag2 0, Pt02 and HgO, lose their
oxygen by a low red heat. Most of them suffer re-
duction by hydrogen, aided by a more or less high
temperature, while carbon, at a red or white heat,
completely reduces all to the metallic state.
Potassium. 131
CHAPTER Y.
POTASSIUM.
Symbol, At. Wt. Sp. Gr. Yal.ency,
K. (Approx.) 0.87.50. I.
39.
L^TASSIUM occurs abundantly in nature, always
however in combination. It is an essential constit-
uent of animal and laud vegetable bodies, and is
found largely in many minerals. The ashes of
land plants, are especially rich in potassium, hence
its name.
Potassium was discovered by Davy in 1807 by
electrolysis ; it is now obtained by heating the car-
bonate with charcoal, e, g.
KCO3 -f- 2C = 3C0 + 2K
The metal, being volatile, distills over, is passed
through naphtha, and condensed to proper form.
It melts at 62.5° (14'4.5F) ; it is soft at common tem-
peratures, and can be easily cut with a knife, pre-
senting a brilliant white surface, which soon
tarnishes, owing to the strong liking it has for
oxygen. For this reason, it soon loses its identity
when exposed to the air, and must be preserved in
some liquid, destitute of oxygen, such as naphtha.
132 Inorganic Chemistry.
Thrown on water, it floats; at the same time caus-
ing equivalent decomposition of that liquid.
H-O-II -f K = K-0— H + H
So great is the chemical energy of this reaction,
that the hydrogen as it escapes from the water, is
set on fire.
Potassium forms several oxides ; the normal oxide,
K2O, being obtained by direct oxidation, or by ac-
tion of potassium on the hydrate.
Potassium Hydrate (hydroxide) KOH, commonly
called caustic potash, is generally prepared by ac-
tion of calcium hydrate fmilk of lime) on potassium
carbonate.
Ca(H0)2 + K2CO3 = CaCOg + 2K0H
Calcium Potassium Calcium Potassium
Hydrate. Carbonate. Carbonate. Hydrate.
Potassium hydrate is a white, soluble, deliques-
cent solid ; strongly alkaline, caustic and poison-
ous.
Potassium carbonate, K2CO3, is the familiar sub-
stance, potash. It is prepared from wood ashes,
and by various other chemical processes ; when re-
fined it is known as pearlash ; it has a strong alka-
line reaction, is soluble in water, but insoluble in
alcohol ; is used in preparing other potassium com-
pounds, and for the making of glass and soft soap.
By treatment with carbonic acid it produces the
" bicarbonate."
Potassium.. 133
K.COs + H2CO3 = 2KHCO3
Carbonic Potassium
Acid. Bicarbonate.
The bicarbonate is also called the hydrogen car-
bonate, and acid carbonate, although it is mildly
alkaline.
Potassium chloride, KCl, obtained principally from
sea water, is a colorless solid, soluble in water, and
is found in the juices of animal bodies.
Potassium Iodide, KI, is prepared by the action
of iodine on potassium hydrate. It occurs in color-
less cubical crystals, of sp. gr. 3, soluble in water
and alcohol.
Potassium Bromide, KBr, is similar in appearance
to the iodide, and is obtained by an analogous
process.
Potassium Chlorate, KCIO3, is prepared by passing
chlorine through a solution of the carbonate; or
through a solution of the chloride, containing milk
of lime.
KCl-H3Ca(OH)2+6Cl=3CaCl2H-3H20+KC103
It is a colorless crystalline anhydrous solid, solu-
ble in 20 pju'ts of cold water. When heated it
gives up all of its oxygen, and when mixed with
combustible matter, like sulphur, tannin, etc., it
becomes explosive. With phosphorus it is largely
employed in the making of instantanoous-Jight
matches.
134 Inorganic Chemistry.
Potassium nitrate^ KlJ^Og, commonly known as
saltpeter and niter, occurs naturally in the soil,
from oxidation of ammonia in the presence of po-
tassium compounds.
Potassium nitrate crystallizes in anhydrous six-
sided prisms, soluble in 7 parts of water.
It is prepared in large quantity by reaction be-
tween Chili saltpeter and crude potassium chloride.
Na:^03 + KCl = NaCl + KNO3
When heated in the presence of combustibles, it
gives up its oxygen ; hence it is used in the manu-
facture of gunpowder and in nearly all pyrotech-
nic compositions, which accordingly burn inde-
pendently of atmospheric oxygen. Average gun-
powder is a mechanical mixture of niter, charcoal
and sulphur, in the following proportions:
KN03
75
0
15
s
10
100
The force of the explosion of gunpowuer is due
to sudden formation of gases and their immediate
expansion by the heat. All of the powder is at
once vaporized, and although the chemical reaction
is really complicated, it may be ap [proximately
represented by the following equation :
2KKO3 + 3C + S = K^S + 3002- + 21S"
Potassium. 135
Potassium Permanganate, K2Mn20g, is prepared
from mixed aqueous solutions of potassium chlo-
rate and manganese dioxide, by evaporating to
dryness, and gently heating. It occurs in dark
purple crystals, of a pleasant, astringent taste ; dis-
solves easily in water, conferring a deep lilac color,
which may be decolorized by Fowler's solution.
It is a powerful oxidizing agent, used in chem-
ical analysis, and for destroying putrid matter.
Potassium forms a great many other compounds,
such as the perchlorate, bromate, iodate, sulphide
and sulphate, phosphates, borates, silicates, etc.,
their consideration, however, in this connection is
unnecessary.
Materia Medica. — Some of the potassium salts
produce active local eifects. The hydroxide is
one of the most penetrating caustics, owing to its
removal of water from the tissues, and saponify-
ing the fats.
The disadvantage of its penetrating qualities, is
somewhat overcome by combination with lime ; its
use as a free caustic has been practically aban-
doned.
The permanganate, on account of its giving up
active oxygen to organic matter, is an excellent
disinfectant in fetid odors and as a gargle in gan-
136 Inorganic Chemistry.
grenous conditions of the mouth and throat.
Dose, 0.06 Gm. (gr.j).
The nitrate and chlorate are employed in solution,
or powder, on inflammatory mucous membrane of
the mouth and throat. The latter drug especially
is effective in mercurial stomatitis.
When taken internally the potassium salts, as a
rule, weaken the normal functions of the brain,
including the co-ordination of motion, reduce the
reflex sensibility of the spinal cord and nervous
system generally. They also cause a lowering
of the heart's action, of respiratory movement
and of temperature. The secretion of saliva is
lessened, and of the gastric juice increased. It may
be well to mention here that alkalies, in moderate
doses, decrease the secreting power of those glands
which normally secrete an alkaline fluid, like the
parotid glands, and increase the power of glands
which secrete an acid, like those of the stomach.
Acids have precisely the opposite eflect.
Most of the salts of potassium are diuretic and
slightly purgative.
The chlorate, in doses of 0.50 Gm. (gr.viii) is indi-
cated in mercurial salivation, aphtha, and ordinary
tonsillar inflammation, suggesting at the same time
a local exhibition of a strong solution as a wa&h or
gargle, or in the form of trochisci.
Potassium. 137
The Bromide is reputable as an antispasmodic
and nervine sedative, and is given in epilepsy, de-
lirium tremens, convulsive seizures of children due
to dentition, laryngismus stridulus, acute mania
and loss of sleep.
The Iodide, unlike the chlorate, increases the se-
cretion of saliva, sometimes to the point known as
iodism.
Doses: Pot. chlorate, 0.65 Gm. (gr.x).
Pot. nitrate, 0.65 Gra.
Pot. bromide, ] a r.?- onn r> r \
Pot. iodide. I 0-6O-200 Gm. (gr.x-xxx).
R. Potassii chloratis, 8 Gm. (^ii).
Aqua, 250.00 fGm. (f^viij).
M. S. A gargle in stomatitis.
12
138 Inorganic Chemistry,
CHAPTER VI.
SODIUM.
Symbol, At. Wt. Sp. Gr. Valency,
:N'a. 23. 0.97. I.
Sodium was discovered by Davy in 1807 by elec-
trolytic decomposition of soda. It is a very abun-
dant element, existing in enormous quantities as a
chloride; in sea water, as rock salt, in salt lakes
and mineral springs, in marine plants, and as a
necessary constituent of animal juices.
Large deposits of the nitrate. Chili saltpeter, car-
bonate, and borate, occur in nature, also sodium
and aluminum fluoride, and sodium silicates.
Sodium is a white soft metal; it melts at 95.5°
(204 F). It decomposes water, but not with as
much energy as does potassium; if the water, how-
ever, be warmed, or thickened with starch, the es-
caping hydrogen will ignite. The reaction corre-
sponds to that of potassium.
Sodium chloride, I^aCl, common salt, is obtained
by mining rock salt, and by evaporating salt water.
It is a transparent, colorless, crystalline, anhydrous
Sodium. 139
solid of sp. gr. 2.15, of an agreeable taste, slightly
deliquescent, and dissolves in 3 parts of water.
There are two oxides of sodium, !N'a2 0, and
Na^O.^, of no practical importance.
Sodium hydrate, or hydroxide, NaOH, caustic
soda, is formed and held in solution when sodium is
thrown into water; it is, however, practically pre-
pared from the carbonate, in the same way that
caustic potash is obtained. It is strongly- alkaline,
but not so active a caustic as the potassium salt.
Its use in commerce is for refining fats and oils,
and in making hard soaps.
Sodium Carbonate, ^2^,^00^, is manufactured
by several processes, but is mainly obtained from
the chloride, by the " Leblanc process," the de-
scription of which is unnecessary. It crystallizes
with 10 molecules of water, Na2CO3,10H2O, and is
the "sal soda" of the laundries. When devoid
of water, or dry carbonate, it is used in very larg^e
quantities in the making of glass and soap.
Sodium carbonate is strongly alkaline, owing to
the strong base and the weak acid, in its compo-
sition. If it be subjected to the direct action of
carbonic acid, the ''' bicarbonate,'^ N'a HCO3, a mild
alkali will be produced. This is the cooking soda
of the kitchen, is an ingredient of all baking
140 Inorganic Chemistry.
powders, and of many effervescent drinks, and is
also used in medicine.
Sodium Borate Na20,2B203, IOH2O borax, occurs
native, in colorless crystals, slightly effervescent,
and mildly alkaline ; soluble in water and glycer-
ine, bat not in alcohol. It is used in the arts as a
flux in melting, soldering, and welding certain
metals. When heated, it swells up, losing its
water of crystallization, and then subsides as a
vitreous mass (borax glass), which is removed from
the surface of the soldered metal, by dilute sul-
phuric acid. A solution of borax (or solutions of
sodium carbonate, or of alum) will render dried
plaster casts comparatively hard.
Other compounds of sodium are numerous, and
some of them important; they resemble for the
most part, the corresponding compounds of potas-
sium.
Materia Medica. Sodium Chloride is a flesh
preserver, and may be considered a good prototype
of antiseptics in general. .
Laharraques Solution, liquor sodse chloratse, solu-
tion of chlorinated soda, [N'aCl, NaClO, analogous
to common bleaching powder. Locally, it acts as
a disinfectant, destroying maladorous and infectious
matter, by reason of the free chlorine and free oxy-
gen it evolves, in the presence of acids (carbonic
Sodium. 141
acid of the air) ; for the same chemical reason it is
a good bleacliing agent, if combined with powdered
ahim.
The bicarbonate is used locally as an antacid, and
when mixed with water, as an application to burns
and scalds.
Borax is a mild antacid, antiseptic, refrigerent,
and detergent. It is a useful ingredient of mouth
washes, or gargles, in inflammation of mouth or
throat, combined with sweetening correctives, as
honey, glycerine, etc.
When internally administered the sodium salts
have not the depressing influence on the system
possessed by those of potassium.
Dose. Sodii Bicarbonas, ) i aa /^ /- n
bodn rJiboras, j \fe ^
B. Sodii Boras, 4.00 Gm. (^i).
Mellis.
Aqua aa, 30.00 fGm. (f^i).
M. S. Use as a detergent.
The other metals of the alkalies, viz., lithium,
rubidium, and caesium, are also monads, and are
comparatively rare. They are highly oxidizable ;
ciesium being the most highly electro-positive of
all elements; they decompose water, setting hy-
drogen free, and form alkaline caustic hydroxides.
Ammonium, ^H^, is a hypothetical, univalent,
142 Inorgnnic Chemistry,
electro-positive, compound radical. Although it
has not been isolated, it acts like metals in the
formation of various salts, being developed in re-
actions between ammonia, NHg, and other bodies
containing hydrogen. Thus, ammonia and nitric
acid, HNO3, unite with each other, without setting
any hydrogen free ; the hydrogen of the acid,
probably joins itself most intimately to thelTHg, to
form the radical KH4, which then, like an atom of
potassium, unites with the electro-negative radical,
NO3. ■
NH3 + HNO3 = FH^.NOj
Ammonia. Nitric Acid. Ammonium
Nitrate.
Ammonium salts are numerous, and resemble in
many respects the corresponding salts of the alkali
metals. The hydroxide, NH^ OH, is an alkaline
caustic, which, when dilute, gives up free ammonia,
and is employed by inhalation as a stimulant in
ordinary syncope, and in excessive anaesthetic
narcosis.
The Chloride, J^H^Cl, the ''sal ammoniac" of
commerce, is used as a flux in refining gold ; and
as a local stimulant to indolent ulcers. The car-
bonate, which has a rather complicated formula, is
known as " sal volatile," and is the principal sub-
stance in " smelling salts."
Inorganic Chemistry. 143
CHAPTER VII.
CALCIUM, ETC.
Symbol, At. Wt. Sp. Gr. Valency,
Ca. 40. 1.50. II.
Calcium is not found free in nature, but exists
abundantly in combination. As carbonate it occurs
in limestone, marble, chalk, coral, marl, oyster
shells, Iceland spar, the stalactites and stalagmites
of certain caves, and in bones and teeth; as a
fluoride, sulphate, phosphate, and in many silicates.
The metal itself is brilliant, slightly yellow, some-
what hard, very malleable and ductile, oxidizes
slowly in the air, decomposes water, and when
heated burns with an extremely bright light. It
may be obtained by heating the iodide with sodium,
but singly it is of no practical use.
Calcium forms but one chloride, CaCl2, which
occurs as a waste product in many processes.
Calcium oxide, CaO, lime, is always prepared
on a large scale by heating the carbonate, as lime-
stone, in a lime kiln. The carbonate being com-
posed of calcium oxide and carbon dioxide, the
latter is driven off by the heat, as will be easily un-
derstood by the equation.
144 Inorganic Chemistry.
CaO, CO2 + Heat = CaO + CO2
Calcium Calcium
Carbonate Oxide
(Lime)
Lime is a hard, infusible, white solid. When
slaked with water, which union develops great heat.
Calcium hydroxide, Ca(H0)2, is formed a white,
bulky powder, which, in an excess of water dis-
solves, resulting in a clear alkaline liquid, known
as lime water. Lime water readily absorbs CO^
from the air, as does also milk of lime (whitewash),
and the lime of mortars and cements. It is to this
fact that the hardening of cements, made largely
from lime is due; the absorption of the CO^,
forming a quasi limestone, a true carbonate.
When sand is present, calcium silicate is also
formed.
Calcium Carbonate exists in so many forms in
nature, as already noticed, that its description
seems superfluous. It is soluble in water contain-
ing carbonic acid, as nearly all natural waters do,
therefore such waters, in limestone regions, are
hard. They may be rendered soft by boiling,
which drives off the carbonic acid; or by an al-
kali, like ammonia, which takes up the acid,
whereby the lime salts are precipitated.
It is probably owing to similar reactions that
occasion the deposition of tartar on the teeth.
The fluids of the parotid, and submaxillary
Calcium, etc. 145
glands, holding lime salts in solution, by aid of
the carbonic acid present, upon their egress into
the moutli, meet with free alkalies, the results of
putrefaction change, which take up the carbonic
acid; the removal of the acid, thus, deprives the
saliva (water) of its ability to hold the lime salts in
solution, and they are precipitated.
Calcium sulphate occnrs in nature as alabaster and
selenite and en masse as gypsum, CaS04, 2H2O.
When heated sufficiently, gypsum loses its water
of crystallization, and becomes plaster of Paris;
this plaster readily takes up water again, and
''sets" to a hard solid. It is used in taking im-
pressions, and in forming models of the parts to
be supplied with artificial dentures; and also for
making molds and casts of various kinds.
Calcium Phosphate, Cag (P04)2, bone phosphate, is
found in natural deposits in certain portions of
South Carolina, Florida, and the islands of the
Carribean sea, sup{)Osed to be the remains of vast
numbers of marine animals that were gradually
imprisoned in the now extinct salt water lagoons,
by land appearing between them and the ocean. It
is the principal constituent of bones and teeth; it
is found also in the other tissues, and in calculi.
Prepared as precipitated calcium phosphate, it is a
white, tasteless and odorless powder, insoluble in
13
146 Inorganic Chemistry.
water and alcohol, but freely soluble in even weak
acids.
Calcium Fluoride^ CaF2, iluor spar, constitutes
about two per cent, of human bone and enamel.
Chlorinated Lime, CaCl2 0, bleaching powder,
sometimes improperly called, chloride of lime, is
formed by action of chlorine on slaked lime; oc-
curs as a gray white powder, or in lumps slightly
moist, emitting a faint chlorine odor, soluble in
water, and decomposed by the carbonic acid of the
air (likewise by other dilute acids) into free chlo-
rine, and other bodies. By the influence of the
nascent chlorine on the hydrogen present in the
moisture, active oxygen results. The preparation,
therefore, is an excellent disinfectant and bleaching
agent.
Oxygen is set free en masse, by acting on a so-
lution of the powder with a solution of nitrate of
cobalt.
For bleaching teeth, the dry powder may be in-
corporated with tartaric acid, introduced into the
cavity slightly moistened, and covered with gutta
percha.
Materia Medica. Some of the lime prepara-
tions used locally are sedative and soothing, as
linimentum calcis (lime water and linseed oil), ap-
plied to burns.
Caiciumy Etc. l47
Prepared chalk is probably the basis of all tooth
powders; it acts as an antacid and astringent.
When taken internally, lime and chalk act in the
same way.
The phosphate has been recommended, although
its efficacy is doubtful, as a food supply, whenever
the structural pabulum in growing bones of infancy
and chilehood is deficient.
Doses. Liquor Calcis, 8.00 f Gm. (fsij).
Creta Prseparata, 1.00 Gm. (gr.xv).
Calcii Phosphas. Prsecipitata, 1.50 Gm. (gr. xx).
B. Calcii phos. prsecipit, 4.00 Gm. (51).
Mistura Cretse, 125.00 fGm. (fgiv).
M. S. Give a teaspoonful to child at meals.
The two other elements of the calcium group,
strontium and barium, are comparatively rare and
unimportant, strontium nitrate Sr(N03)^ is used
in making "red fire," barium nitrate Ba(N03)2
in making "green fire." Barium salts are used as
a test for suli)huric acid, and vice versa. Barium
sulphate is known as " heavy spar," and when
ground is used as a pigment.
There are two oxides of barium, and these are
easily changed, the one into the other. BaO heated
in air, is converted into Ba02. This dioxide readily
gives up 0, as in the manufacture of hydrogen di-
oxide, already alluded to.
148 Inorganic Chemistry.
CHAPTER YIII.
METALS OF THE EARTHS, AND SILVER.
The metals of the earths — yttrium, erbium,
samarium cerium, etc. — are quite numerous, but
are found only in a few rare minerals, principally
as silicates. They, and nearly all their com-
pounds, are mere chemical curiosities, except
cerium oxalate, Ce^ (^2^4)3' which is used in
medicine.
SILVER.
Symbol, At. Wt. Sp. Gr. Valency,
Ag. 108. 10.5. i-in.
Silver has been known from the earliest times.
It is found in various countries, in the metallic
state, but principally in combination, as chloride,
iodide-, bromide, sulphide and telluride. The vari-
ous elaborate methods employed for extracting sil-
ver from its ores are interesting from a commercial
chemical point of view, but need not be considered
here.
It is a brilliant white metal, malleable, and duc-
tile, and is the best conductor of heat and electric-
Metals of the Earths , and Silver. 149
ity. It melts at about 1000° (1850 F), does not tar-
nish in pure iiir, although traces of 11.^ S affect it,
as it sulphidizes easily; it is also readily acted on
by CI and P; hydrochloric and sulphuric acids at-
tack it with difficulty, but nitric acid, even quite
dilute, rapidly dissolves it.
Ag. + HXO3 = Ag^O, + H.
Silver Nitrate AgNOg, lunar caustic, is obtained
according to the above equation; by evaporating
the solution, it appears in the form of colorless,
transparent, anhydrous crystals, soluble in water
and alcohol. When melted and cast into proper
shape, it is known as lunar caustic.
Silver nitrate is employed in photography, in the
making of hair dyes, inglelible ink, etc., on account
of its turning dark by the influence of light, when
in contact with organic matter, probably due to the
deposition of argentous oxide.
Silver Chloride, AgCl, is precipitated whenever
a soluble chloride (common salt, etc.), is added to a
solution of silver nitrate. It is a white curdy sub-
stance, insoluble in water and nitric acid, but dis-
solves easily in a([ue()us solutions of ammonia and
potassium cyanide. When heated, it fuses, and on
cooling, assumes a horny consistency, hence the
name of the mineral horn silver.
150 Inorganic Chemistry.
Silver chloride decomposes in the light, rapidly,
when in contact with organic matter; also when
heated with sodium carbonate, or placed in dilute
sulphuric acid with zinc or iron. In the latter pro-
cess, the nascent hydrogen removes the chlorine,
leaving the silver in the form of a spongy mass.
There is another chloride of silver of uncertain
constitution; and three oxides. The normal oxide,
Ag^O, a strong base, which yields salts isomor-
phous with those of the metals of the alkalies.
Materia Medica. The nitrate is the only silver
compound that need be noticed in this connection.
It is employed almost exclusively as a local agent,
and possesses decided caustic properties, by reason
of its coagulating action on albumen ; by this
means, a protecting pellicle is soon formed, which
prevents the caustic action from extending deeply.
It is used to induce healthy granulations in ulcers
and wounds, and when properly diluted, is one of
the most efficacious applications to every variety of
inflammation of the mucous membrane.
Applied in substance to sensitive abraided, or
denuded, or even decayed surfaces of teeth, it re-
lieves the tenderness and arrests the process of de-
cay. On account of the permanent darkening of
the tooth substance to which it is applied, especial
discretion should be observed in its use.
Silver. 151
Dose. Silver Nitrate, 0.01 Gra. (gr. -J).
Antidote, common salt.
B. Argenti Nitras, 0.10 Gm. (gr. jss).
Aqua Dest., 30.00 fGm. (f^i).
M. S. Injection in diseased antrum.
152 Inorganic Cheynistry.
CHAPTER IX.
COPPER, MERCURY.
Symbol, At. "Wt. Sp. Gr. Valency,
Cu. 63. 8.95. 11.
Copper is one of the ancient metals and is still
of great value in the arts. It is found in nature
both native and in combination, as oxide, carbon-
ate, and sulphide, and with iron sulphide as " cop-
per pyrites."
Copper has a familiar yellowish-red color ; is
malleable and ductile and tenacious; is one of the
best conductors of electricity and heat ; melts at
about 1090 (1994-F), is not acted on by dry air,
but in moist air it tarnishes with a green crust,
consisting principally of the carbonate. When
heated, scales of black cupric oxide form on its
surface. Chlorine, sulphur, and nitric acid attack
it readily; in the lalter case, setting free fumes ot
1^^2 02. It also forms salts wnth dilute acetic acid
and hot sulphuric acid, and slowly, with dilute
hydrochloric and sulphuric and carbonic acids, al-
kalies and saline solutions. All sol able salts of
copper are poisons.
Copper, 153
Certain alloys of copper have been mentioned.
Its compounds are numerous, but few of them
need be considered here.
Copper forms two series of salts, the eupric and
cuprous.
Cupric chloride^ CuClj, obtained by dissolving
eupric oxide in hydrochloric acid, and by direct ac-
tion of chlorine. It makes, with water, a green so-
lution which, on evaporation, deposits green crys-
tals containing water, CuClj, 2H2O3. When
heated it loses all its water of crystallization, and
half its chlorine, and is converted into cuprous
chloride, CU2CI2, a white fusible substance, slightly
soluble and prone to oxidation. Both chlorides
form double salts, with the chlorides of the alkali
metals.
Cupric oxide, CuO, or black oxide of copper, may
be prepared by heating copper in air, or by calcin-
ing the nitrate, carbonate, or hydrate. It unites
with most acids, forming cupric salts. With
[ihosphoric acid it forms a hard, tenacious, insol-
uble, black mass, which combination has been
introduced by Dr. W. B. Ames, as a tilling imate-
rial in posterior teeth, for setting crowns, etc. The
mineral libethenite is IlCu^POr.
Cuprous oxide CU2O, red oxide of copper, is like
154 Inorganic Chemistry.
the other cuprous compounds, important only as
conferring a beautiful ruby red color to glass.
Cupric sulphate, CuSo4,5H2 0, blue vitriol, prepared
by dissolving cupric oxide in sulphuric acid, oc-
curs in large blue crystals, and is extensively em-
ployed in electro-metallurgy, telegraph batteries,
calico printing, the making of Paris green, etc.
Materia Medica. — Copper sulphate in substance
is an excellent application to fungous conditions
of the gums, as it acts as an astringent and lessens
the local blood supply, and is a mild caustic.
Internally in large doses it acts as an emetic, in
small doses as a tonic.
Dose. (Emetic), 0.20 Gm. (gr.iij).
(Tonic), 0.02 Gm. (gr. J).
MERCURY.
Symbol, At. Wt. Sp. Gr. Valency,
Hg. 200. 13.59. 11.
Mercury, quicksilver, the argentum vivum, of the
ancients, is found native, but principally as a sul-
phide, cinnabar, extensively mined in California,
Mexico, and Peru, and portions of the old world.
The sulphide is reduced by roasting with lime, the
metal volatilizes and is condensed in suitable
chambers.
Mercury is a brilliant silver- white liquid. At
Mercury. 155
40°C (and F) it solidifies to a tin-like malleable mass
of specific gravity 14.19. It is slightly volatile at
15° (60-F) and boils at 357 (666-F) ; yields a vapor
of density of 100; the molecule of mercury, there-
fore, consists of one atom. Mercury is unaltered
hy the atmosphere, but near its boiling point it
slowly absorbs oxygen, passing into the red oxide,
IlgO. Chlorine and sulphur unite directly with
mercury. Boiling strong sulphuric, and even di-
lute nitric acid attack it easily, but it is unaffected
by hydrochloric and cold dilute sulphuric acids.
Mercury is used in the making of many physical
instruments, as thermometers, barometers, etc.,
and in extracting gold and silver from their ores.
Its alloys are called amalgams. Of these, only
those used for filling careous teeth are of special
interest to us. Copper amalgam is produced by
various processes, among the best, perhaps, being
by electrolysis of copper sulphate in the presence
of mercury. It is a hard amalgam when properly
made; does not change in bulk or shape in set-
ting, and acts as a germicide and antiseptic. It,
however, dissolves in weak acids, and the decidedly
black copper oxide and sulphide which, together,
form on the surface, are probably converted into
copper sulphate, which we know to be freely solu-
ble. Both of these facts combined, or either one
156 Inorganic Chemistry.
singly, can explain satisfactorily the wasting that
80 often takes place in copper amalgam fillings.
Mercury forms with many other metals, amal-
gams of either continued pasty, or hard consist-
ency, according to the metal used. An amalgam
of an alloy of about 50 parts silver and 40 parts tin,
containing also small additions of copper, gold, zinc,
platinum, palladium, antimony, and cadmium, sin-
gly or otherwise, seems to produce the best results in
dental practice. The blackening of amalgam fillings
is due to the formation of metallic sulphides, and
is considered a not unmixed evil ; the more em-
phatically blacky the better the preserving qualities.
Mercuric chloride, HgCl2, bichloride of mercury,
corrosive chloride, corrosive sublimate, etc., is usu-
ally prepared by subliming a mixture of sodium
chloride and mercuric sulphate.
2XaCl + HgSO^ = Na^SO^ + HgCl2
Sodium Mercuric Sodium Mercuric
Chloride. Sulphate. Sulphate. Chloride.
Mercuric chloride is a semi-transparent crystal-
line heavy solid, of an acid metallic taste, and acid
reaction. It is soluble in 16 parts of cold, and 2
parts of hot water, 3 of ether, and 2 of alcohol,
and is a strong corrosive poison.
Mercurous chloride, Hg2-Cl2, proto-chloride of
mercury, mild chloride of mercury, submuriate,
calomel, etc. Calomel occurs native, in tetragonal
Mercury. 157
crystals, but is commercially prepared by sublim-
ing a mixture of sodium chloride, mercuric sul-
phate and mercury.
2NaCl + HgSO^ + Hg == Na,S04 + Hg2Cl,
Mercurous
Chloride.
A heavy white, iine powder condenses, insoluble
in water, and alcohol, tasteless, and decomposes
slowly in sunlight into freeHg andHgCl^.
31ercuric oxide, HgO, occurs in red scales, when
mercury is heated in air, commonly as red precipi-
tate. It forms with acids, mercuric salts.
JflercuroiLS oxide, Hg^O, a black powder, produced
by action of alkali-hydrates on calomel. With
acids it forms mercurous salts. There are two
iodides of mercury analagous to the chlorides.
Mercuric sulphide, HgS, has already been alluded
to as the mineral cinnabar. When made synthet-
ically it is known as tlie brilliant red pigment,
vermilion.
Mercurous sulphide Hg.^S, is a black powder,
known as ethiopes mineral.
f CI
Mercuric chloramide, ITg -| ^^ is known as
white precipitate.
Materia Medica. — Mercurial preparations are
favorite local remedies in certain skin diseases and
syphilitic ulcerations, in virtue of their germicidal
and antiseptic properties. The practice of steril-
158 Inorganic Chemistry.
izing instruments in hot solutions of mercuric chlo-
ride is effective, although the efficacy of a cold
solution might be questioned. A cold aqueous so-
lution of this drug has been a favorite germicide
in sterilizing root canals of teeth, preparatory to
fining. It forms, with albuminous matter, a coag
ulum of only temporary existence, consequently,
the duration of asepsis, secured by it, is limited •
and unless the disease germs, held in the coagulum,
are immediately killed by it— a wished-for consum-
mation, the occurrence of which, many deny — its
virtues as a germicide and antiseptic woultT be
active only during the period of coagulation ; and
if more or less organized matter remain in the ca-
nals, at the time of filling, a condition that unfor-
tunately sometimes obtains, its coagulation by cor-
sosive sublimate, would therefore be of doubtful
permanent efficiency. The salts of mercury, nev-
ertheless, appear to possess especial destructive
power over the germs of syphilis at least, and a
wash of corrosive sublimate solution, used before
operating in the mouth of a syphilitic patient,
would sterilize the part for the time being.
Taken internally, the salts of mercury if pushed
to the limit, occasion nervous debility, and cause
anaemia by destroying the red corpuscles. They
increase the secretion of saliva, mercurial salivation
31ercury. 159
sometimes following their use. Antidote to mer-
curic chloride — emesis, albumen, white of ^gg,
milk, flour.
Dose. Mercuric Chloride, 0.004 Gm. (gv. yL).
Mercurous Chloride, 0.30 Gm. (gr. v).
R. Hydrarg Chlor. Corrosiv. 0.10 Gm. (gr.jss).
Acidi Hydrochlorici Dih, q. s. ad. solve.
Mellis Depurati, 15.00 fGm. (f^ss).
Aqua Dest., q. s. 150 fGm. (f 3 v).
M. S. To be used as a wash, or gargle, in syphiUtic
ulceration of mouth and throat.
160 Inorganic Chemistry.
CHAPTER X.
ZINC, ETC.
Symbol, At. Wt. Sp. Gr. Valency,
Zn. 65. 7. 11.
The chief ores of zinc are the sulphide, carbon-
*
ate. oxide, and silicate. These are calcined in air,
producing zinc oxide; the latter is then distilled
with charcoal (C), which takes up the oxygen, the
zinc vapor condensing in suitable vessels.
2ZnO + C := CO2 + 2Zn
Zinc is a bluish white metal. At ordinary temper-
atures it is hard and brittle ; at about 150° (300°F),
it becomes quite malleable ; at 200° (392° F), it again
becomes brittle, and may be broken up in a mor-
tar; at 412° (773°F), it melts, and at about 1000°
(1832°F), if air be present, it volatilizes and burns
with a splendid greenish light, forming its only
oxide, ZnO. Zinc is slowly oxidized in moist air,
and is acted on easily by dilute acids, by alkali-
hydrates, and by the halogens. It is used largely as
a protecting coat for sheet iron; it forms the posi-
tive element of galvanic batteries, in making dies
for swaging dental plates, as a constituent for some
Zinc. 161
amalgams, and of other highly valuable alloys, as
brass, etc.
Zinc chloride, ZnCl2, is made by direct action of
chlorine upon zinc, or by dissolving granulated zinc,
or zinc carbonate in hydrochloric acid, purifying
by solution of chlorine and zinc carbonate, and
evaporating the solution to dryness. It occurs as
11 grayish-white translucent, cr^^stalline mass, deli-
quescent, and very soluble in water, and in alcohol,
and ether. Liquor zinci chloridi, is the official prepa-
ration, and contains 14.00 Gm. (5 ijjss) of zinc chloride
to 30.00 f Gm. (fSi) of water. The solution for oxy-
chloride cement should have a sp. gr. of about 1.50.
Aside from its use in surgery, zinc chloride is em-
ployed as a chemical dehydrating agent; that is, it
will not only take away water, but the elements of
water from organic compounds (and from albumin-
ous organized structure, which probably explains
its action as a caustic). It is also used as a solder-
ing fluid.
Zinc oxide, ZnO, is the product of the combus-
tion of zinc in air; it is used extensively as a pig-
ment. The pharmaceutical preparation is obtained
by subjecting pure precipitated zinc carbonate to a
red heat, until all the water and CO.^ are driven ofl'.
It should appear as a white, smooth, impalpable
powder. It is tasteless, and insoluble in water, but
14
162 Inorganic Chemistry.
is acted upon by the common dilute acids. It is
the basis of the various zinc cement preparations,
mixed with variable quantities of silica, borax, pul-
verized glass, etc
The liquid for the oxychloride has already been
described; that for the oxyphosphate consists of
tri-basic phosphoric acid, II3PO4, prepared by dis-
solving pure glacial phosphoric acid, HPO3, in
warm water and evaporating to a syrupy consis-
tency.
In preparing the filling, the powder should be
added to the liquid slowly, and mixed thoroughly,
until the magma has a stiff, tenacious feel, then in-
serted in place, and kept dry for 20 or 30 minutes.
The result will be a hard coherent filling, of rea-
sonably lasting qualities, depending more than less,
on its position in the tooth. Chemical union be-
tween "the acid, and the zinc oxide of the powder,
undoubtedly takes place; the other ingredients
of the powder being held mechanically; but this
union can be overcome by either acids or alkalies.
It is known that these fillings give way rapidly at
the cervical wall, if under, or near the gum mar-
gin ; such positions are most favorable to develop-
ment of alkalies, by putrefaction (ammonia, and its
derivatives, the amines, a^iiides, ptomaines, etc.),
and also somewhat to acid fermentation. The alkali
Zinc. 163
will appropriate its equivalent of the phosphoric
acid, the cement losing its integrity to that extent;
while the acid stage of fermentation, if such should
occur, would tend to destroy the cement, by at-
tracting the oxide of zinc. In such a situation
the oxyphosphate fillings are, evidently, ^'between
the devil and the blue sea."
Zinc sulphatCy ZnS047Il20, white vitriol, obtained
by the action of sulphuric acid on granulated zinc,
occurs in small, colorless, efflorescent crystals, solu-
ble in water, insoluble in alcohol, and of a metallic
styptic taste.
Materia Medica. Zinc chloride is a powerful
caustic, owing to its dehydrating qualities. It is
employed in substance, or strong solution, for treat-
tnent of cancerous and other forms of ulceration.
As an obtunding agent to sensitive dentine, it is
affective, although superficial ; but on account of
the pain immediately following, and the danger to
the vitality of the pulp involved, the practice of
applying it as a dentinal obtundant, has been nearly
abandoned. In solution, it is successfully employed
as an injection in chronic alveolar abscess, in an-
trum disease, and in the gum pockets of alveolar
pyorrhoea.
The sulphate acts locally as an astringent and
stimulant.
164 Inorganic Chemistry.
Internally, the sulphate is tonic, antisposmodic
and astringent. In large doses it is the favorite
direct emetic.
Dose. Zinc Chloride 0.03 Gm. (gr.ss.)
ZiDc Sulphate 0.06-0.30 Gm. (gr. j-v.)
As au emetic — Zinc Sulphate 0.65 Gm. (gr. x.)
Antidote, Sodium bicarbonate.
B. Zinci Chloridi 0.06 Gm. (gr.j).
Aqua Rosse 30.00 fGm. (fgi.)
M. S. A good injection, Antrum, etc.
MAGNESIUM.
Symbol. At. Wt. Sp. Gr. Valency.
Mg. 24. 1.75. II.
Magnesium is an abundant element, but is always
found in nature in combination. The double car-
bonate of magnesium and calcium MgCa2C03 is
known as dolomite or mountain limestone, of which
whole mountain ranges are formed. The metal
also occurs in the single corbonate, the sulphate,
h^^drate, fluo-phosphate, chloride and several sili-
cates, of which latter class, meerschaum is one
(2MgO SiO^).
Salts of Magnesium are found in sea water and
many mineral springs, also in animal and vegetable
bodies.
The element itself is generally obtained by heat-
ing the chloride with metallic sodium.
Magnesium. 165
MgCl2 + 2Na = mixQl + Mg
Mafj:iicsium Chloride.
It is a bluish white brittle metal, somewhat mal-
leable and ductile; melts at a red heat; is not af-
ected by dry air, but oxidizes in moist air. Heated
to redness, it takes fire, and burns with an ex-
tremely brilliant white light, very rich in the ac-
tinic chemically active ways; for this reason it is
used as a source of illumination, in photographing
the interior of caves, etc.
Magnesium Oxide, MgO, is a white, infusible, in-
soluble, bulky, antacid powder, known as magnesia.
Magnesium Sulphate, MgSo^ 7H2O, is found in
nature, as Epsom salts, and may be prepared by
dissolving the oxide, hydrate, or carbonate, in sul-
phuric acid. It consists of colorless, odorless,
soluble crystals, of a bitter taste; used in medicine
as a purgative.
An interesting feature in connection with the
water of crystallization in MgS04 TH^O, is worthy
of notice. At a temperature of 120° (248F.) only
six of the seven molecules of water are driven off;
the remaining molecule persistently resisting ex-
pulsion until the temperature reaches nearly 200°
(892F). This last is known as water o^ constitution,
and may be replaced by certain sulphates, as for
instance K2SO4, yielding a doable sulphate.
166 Inorganic Chemistry,
SO.K
MgSO,, H^O 6H2O + K^SO, = Mg{ ^^^^ } 6S0,
I pi rj Potassio-Magnesium
^^^2^ Sulphate.
This compound serves as a type of double salts,
and is isomorphous with those produced by the
union of the alkali-sulphates, with the sulphates of
zinc, copper, nickel, iron and cobolt
Potassio-Ferrous Sulphate,
Showing also that there is some chemical relation-
ship between magnesium and the metals just
named.
Cadmium (Cd), is comparatively rare, occurs
chiefly as an impurity in zinc, and as a sulphide;
the precipitated sulphide, CdS, is a yellow pigment
of great beauty, highly prized by artists. Cad-
mium is obtained by converting the sulphide into
oxide, and reducing the latter, by heating with
charcoal. It is a lustrous bluish-white, tinlike
metal, of sp. qr. 8.6, at. wt. 112, vapor density
one-half the atomic weight, hence its molecule is
composed like that of mercury, of only one atom.
It melts at 260° (500F.) • tarnishes gradually in the
air, and is acted on slowly by acids, and by chlo- .
rine, sulphur, and oxygen. Its salts resemble those
of zinc; the metal itself is malleable and ductile,
Cadmium- GrlucinuM. 167
but of no importance, except as a constituent of
some fusible, and amalgam alloys.
Beryllium or Glucinum, (G1), is a rare metal,
occurring in certain silicic minerals, and as an ahi-
minate. It is a white metal of sp. gr. 2.1 mallea-
ble, and sets hydrogen free from acids. Its salts
have a sweetish tasts, whence its former name,
gluciniun.
168 Inorganic Chemistry.
CHAPTER XI.
LEAD, ETC.
Symbol, At. Wt. Sp. Gr. Valency,
Pb. 206.5. 11.40. II-IV.
Lead was well known to the ancients, and is still
an abundant and useful metal. It is found princi-
pally as a sulphide in galena, but also occurs as a
carbonate, sulphate, phosphate and arsenate.
Lead is a bluish-white metal, soft enough to be
easily cut with a knife. The brilliant freshly cut
surface quickly tarnishes in moist air. It is malle-
able and ductile, but possessed of very feeble te-
nacity ; melts at 320 (608F) ; is acted upon by
nitric, sulphuric, hydrochloric, carbonic, and acetic
acids, and by oxygen, sulphur, chlorine, bromine
and iodine.
All the salts of lead are poisonous. Waters con-
taining nitrates from decomposed animal matter,
and clorides, are not safe when passed through lead
pipes. Hard waters, how^ever, containing carbon-
ates, and sulphates, are relatively safe, as the lead
carbonate forms an insoluble protecting crust on
the interior lining of the pipe, unless a considera-
ble amount of free carbonic acid is present. As a
Leady etc. 169
precaution it is best to allow water that has been
long standing in lead pipes, to flow until the fresh
portion from the mains appears. Lead salts in
water can be detected by adding a few drops of hy-
drochloric acid and then a strong solution of sul-
phuretted hydrogen. If lead is present, a dark
brownish color will result.
Cylinders of metallic lead have been successfully
employed for filling root canals of teeth, the lead
sulphide and carbonate, formed therein, probably
acting as antiseptics, but as these salts, especially
the sulphide, injure the normal color of the tooth,
the practice of using lead for such purposes, is not
much in vogue. In dentistry lead is more espe-
cially used for making counter-dies. In the arts it
is used alone, and alloyed with other metals, for
various purposes.
Its compounds are important. Lead oxides are
used as coloring for porcelain teeth. The hydrated
carbonate, 2PbC03, (H0)2,is the basis of the well-
known paint, ivhite lead. The monoxide, PbO, is
known as litharge, and this, if heated in a current
of air, is converted into red lead, PbgO^.
Materia Medica. — All the salts of lead are
used, as a rule, only as external applications.
They are soothing and astringent. The acetate,
15 : : •'■'• ':'.' /-. '•':'• •'
170 Inorganic Chemistry.
Pb(C2 11302)27 sugar of lead, is sometimes given
internally as an astringent, in diarrhoea and
haemoptyses.
Lead poisoning (painters' colic), indicated by a
blue appearance along the gum margins, muscular
weakness (drop wrist), constipation, etc., is a fre-
quent affection of workers in lead pigments.
Antidotes. — Soluble sulphates, as magnesium
sulphate, which cause formation of insoluble, and
therefore, innocuous lead sulphate, followed by pot-
assium iodide and sulphur baths.
Dose of lead acetate (sugar of lead), 0.10 Gm. (grjss)
The metal ThalliUxM (Tl), discovered by Crookes
in 1861, by aid of the spectroscope, is a very rare
element, although widely diffused ; occurring in
very small proportions in iron and copper pyrites
and in native sulphur. It is obtained from the
flue-dust of sulphuric acid works. Although it is
a triad, it resembles lead in nearly all its proper-
ties. Its atomic weight is 203. The salts of Tl
color the flame a brilliant green.
TIN.
Symbol, At. Wt. Sp. Gr. Valency,
Sn. 1.18. 7.29. II-IV.
Tin is one of the metals of earliest antiquity.
The principal ore of tin is the mineral cassiterite
c c «■
Tin, 171
stannic oxide, SnO^, found from time immemorial
in England (Cornwall). Tin is now produced also
in Borneo, Malacca, Banca, and to some extent in
the United States, South America, and Australia,
the purest coming from the island of Banca.
The metal is obtained by heating the crushed ore,
with coal or charcoal, Sn02 + C = CO^ + Sn. It
is soft, white, crystalline, malleable, slightly duc-
tile, and feebly tenacious. Melts at 235° (455F),
has a peculiar odor, and " cries " when a bar of it
is bent ; retains its luster in air at common tempera-
tures, but if heated, oxidizes readily ; is acted upon
by dilute acids, and by the alkalies.
Tin is used largely in the arts; common tin plate
is sheet iron, coated with tin, by immersion. Tin
enters into the formation of many important alloys,
and is used by dentists in the form of foil, as a fill-
ing material, alone, and in mechanical combination
with gold. The high preserving qualities of tin in
this connection, are doubtless due to the formation
between the filling, and the walls of the cavity, of
the insoluble stannic oxide, and when with gold, in
addition to this, an electrolytic mutual induction
continues between the two metals, like that w^hich
exists in, and preserves, galvanized iron, (iron and
zinc).
There are tiro sets pf.tin compounds. The two
172 Inorganic Chemistry.
chlorides, viz. : SnClg and SnCl4, plus water of crys-
tallization, are used as mordants in calico print-
ing. These two chlorides, obtained by dissolving
tin in hydrochloric and nitrohydrochloric acids re-
spectively, yield with auric chloride, the beautiful
" purple of Cassius," which is used in coloring por-
celain.
Stannous oxide, SnO, is basic, and with acids
forms a number of salts.
Stannic oxide, SnO 2, is peculiar, when compared
with those metallic oxides we have thus far con-
sidered, in being neither decidedly basic, nor acid;
it is weakly basic with strong acids, and weakly
acid with strong alkalies. This oxide is known as
futty powder.
There are two acids of tin, whose formulas will
serve to explain the meaning of the prefixes, ortho
and meta, which are sometimes attached to the
names af certain acids and salts. Or^Aostannic acid,
H4Sn04, has four hydroxyl groups in its molecule ;
all its oxygen has a linking function, as the graphic
formula will show :
0— H
H— O— Sn— 0— H
)— H
— Sii — being a..tetrad,«;Beqjiiri5s four groups of
A.
< •
< • <
Tin. 173
hydroxyl (0H)4, to satisfy its equivalency oi four.
In all ortho-acids, there should be as many hydro-
gen atoms as oxygen atoms; that is, the number
of hydroxyl (OH) groups should be the same as
the valency of the receiving radical, which, in the
case of Sn, is four. Phosphorus is a pentad, P^
Ortho-phosphoric acid should therefore have jive
hydroxyl groups P(0II)5.
yifefa-acids are derived from ortho-acids by ab-
stracting a molecule, or molecules of water, from
the latter. In meta-acids the atoms of oxygen serve
a saturating as well as a linking purpose Thus,
Meta-stannic acid, H2Sn03, is ortho-stannic acid,
minus one molecule of water:
0-H 0
I II
H-O-Sn— 0-H H— 0-Sn
0-H 0-H
Ortho-Stannic Acid. Meta-Stannic Acid.
Where tino molecules of water can be removed
from an ortho-acid, a r/me^a-acid results; Mree mole-
cules of water removed, a trimeta-acid, etc.
0-H 0
I II
H-O^P -0-H H-0^^
H-0^ ^0-H 11-0--" ^^0-H
Ortho phosphoric Acid. Metn-phos. Acid.
o
H-^0 ^:r--^.0=i=HPOv, etc.
' , M)tn^i;»a-«pbc«.»i'.c\d. .
•'• ••» >
"i^V:-... ..,
174 Inorganic Chemistry.
The salts of ortho and meta-acids are named with
corresponding prefixes.
Stannic sulphide, SnS2, is a golden yellow pow-
der, called " Mosaic gold," used for bronzing.
Materia Medica. The medicinal value of tin
compounds is nil.
Titanium, Zirconium and Thorium, belong to the
tin group of elements. They are extremely rare;
are tetrads, like carbon, silicon, and tin, to whom
they are closely related in the gradation of their
physical properties, and in the similarity of their
chemical compounds. The gradation being in the
following order :
Carbon, Silicon, Titanium, Zirconium, Thorium,
Tin.
• •••• • ••• •*; I
\: '.: r- -.:>-
1 • • •
• • •
• • •
Aluminum, 176
CHAPTER XIl.
ALUMINUM, ETC.
Symbol, At. Wt. Sp. Gr. Valency,
Al. 27. 2.6. IV.
Aluminum next to oxygen, and silicon, is the
most abundant of the elements, the crust of the
earth being made up mainly of those three. The
minerals, corundum, emer}-, ruby and sapphire,
are aluminum oxide, and the various kinds of clay,
as well as feldspar, mica, slate, granite, basalt, etc.,
are essentially aluminum silicates. Hydraulic
cement contains al-silicate.
The process of Deville, discovered in 1854, of
heating together in a reverberatory furnace a defi-
nite mixture of fluor spar, sodio-aluminum chlo-
ride and metallic sodium, furnishes a clue to the
mothod^ ad()})ted, for obtaining the metal.
AL.dg + Nag = 6NaCl + 2A1
This process has been superseded of late years
by various modifications, by which aluminum is
produced almost pure, (98 per cent), and compara-
tively inexpensive.
Aluminum is a brilliant bluish-white metal, sus-
ceptible of receiv^ng^d'iiigh 'j>o(i'4J!i,;'i8 very malle-
> > » > I
> » » I ,
' "• '.'•.';.,;
176 Inorganic Chemistry.
able, ductile, and possessed of considerable tenacity.
It is acted on by aqueous solutions of strong alka-
lies and hydrochloric acid, but is unaffected by
other cold acids, inorganic or organic; is not af-
fected by sulphur, and therefore may be conjoined
with rubber in vulcanizing the latter substance ; it
does not oxidize in bulk, but if thin leaves be
heated in oxygen, it burns readily. It melts at
700° (1292F).
On account of its lightness, permanent purity,
and the tensile strength of the metal and its alloys,
it is being largely introduced of late into the arts
for many purposes. It can be cast alone or alloyed
with silver or copper, into forms of singular
beauty. 10 parts silver and 90 of aluminum ex-
hibits a splendid white non-corrosive alloy; 90
parts of copper and 10 of aluminum, constitutes
aluminum bronze, resembling gold in color, and ca-
pable of receiving and retaining a high polish.
In thin leaves it has been used, with some euccess,
as a lining for rubber plates. An alloy of 100
parts of aluminum and 10 of tin, is employed in
the making of philosophical instruments. The
apex of the Washington monument is of alu-
minum.
Aluminum plates, either cast or swaged for arti-
ficial dentures, ka>ve \tak$ii*:£5n important rank in
••• • » •«••• .... •• • ••••
«• • ••• •••
• •«• « •**
• • • •
, • • • •: • • •,
Aluminum. 177
dental prosthesis. They possess special properties
often requisite for certain mouths.
Alum, from which the metal takes its name, is
the most important compound of aluminum. Com-
mon potash alum is a double sulphate of aluminum
and potassium, Al2(S04)3,K2S04,24H20, or AI2
K2 (80^)4,241120. Ammonium alum is Al2(]SrH4)2
(804)4,241120. There are alums also of Xa,Cs,
Rb, Ag, and Tl, wherein these elements respect-
ively occupy the place of K or NH4 ; and there
are alums in which the aluminum itself is replaced
by Fe, Cr, and Mn, respectively. Each molecule
of alum contains 24 molecules of water of crystal-
lization.
Ordinary alum is manufactured on a large scale
by action of sulphuric acid on some of the various
aluminum silicates, whereby aluminum sulphate,
AI2 (804)3, is formed. This is then added in solu-
tion, to a solution of potassium sulphate K2SO4,
Or ammonium sulphate NH48O4, as the case may
be. The alum crystallizes on evaporation of the
liquid mixture.
Alum has an astringent sweetish taste, and acid
reaction; is soluble in water, the hot solution be-
ing a good pickle for removing borax glass from
gold, etc., after soldering. By heating for a con-
siderable time, at a temperature of 80° (176F), all
178 Inorganic Chemistry.
the water of crystallization is driven out, the alum
then becoming caustic alum.
Aluminum Oxide, AI2O3, alumina, is found crys-
tallized in nature, in many varieties, as corundum,
emery, ruby, etc.; colored by impurities, as sapphire,
which is simply blue corundum; "oriental amy-
thist" is purple, "oriental topas" is yellow, and
"oriental emerald" is green. These gems can be
produced artificially.
The oxide is prepared by igniting the hydrate (the
latter obtained by mij{:ing a solution of alum with
excess of ammonia), presents a white, tasteless, co-
herent mass, very slightly afiected by acids, and
fusible only in the oxyhydrogen flame.
The hydrate Al2(H0)g ortho-aluminum hydrox-
ide, prepared as above, forms with strong acids,
characteristic salts, like al-sulphate, already men-
tioned. With basic radicals, it acts as an acid,
forming aluminates, as ortho-sodium aluminate,
^agAlgOg. There are also the mono-meta hydrox-
ide, Al2 0(HO)4, and the dimeta-hydroxide, AI2O2
(HO) 2, forming with bases, mono-meta and dimeta-
aluminates, respectively, as dimeta-potassium alu-
minate, K2AI2O4, etc. Aluminum" hydrates are
largely used in calico printing, as mordants, inas-
much as they are able to unite with organic dye-
stuffs, to form "lakes," which are insoluble; the
Aluminum. 179
(litfereut colors being thus "fixed" in the fiber of
the cloth.
There are normal, and basic {i. e., containing hy-
drogen), aluminum phosphates found in nature, of
which, the turquoise, Al4(r04)2,(HO)g,2H20, is an
example. The topaz is fiuo-aluminum silicate, the
beautiful blue " lapis lazuli" is sodio-aluminum sili-
cate, containing sulphur. Its powder was formerly
used by artists, under the name of " ultra marine."
This substance is now produced very cheaply ; vio-
let, red, and green ultra-marines are also prepared
artificially.
Clay is the result of the disintegration of the ua-
stratified, primitive rocks, as granite, porphyry, etc.,
and further of felspar, etc., these rocks consisting,
in great part, of this mineral.
The art of pottery making has been known from
the earliest times. Porcelain manufacture, in Eu-
rope, is of comparatively recent date, being derived,
probably, from China, whence the name " China-
ware." Porcelain differs from pottery, in being
translucent, and differs from glass in being non-
transparent, and much more infusible.
Porcelain clay, or kaolin, is a hydrous aluminum
silicate — , II2 Al2Si20g,H20, derived by atmos-
pheric influence on felspar, which is K2Al2SigOig.
When prepared for the furnace, and baked, it loses
180 Inorganic Chemistry.
its water, yielding a porous " biscuit." This is
dipped in a thin mixture of pure felspar and water,
and "fired" again; the felspar being fusible,
"glazes" the surface into a smooth finished pro-
duct. The ornamental part, of gilding, and paint-
ing in enamel, is next accomplished, and the piece
(pieces) heated again to flux the colors. The colors
consist ofpigments of metallic oxides ; cobalt oxide
for blue, chromic oxide for green, etc.
Crucibles and fire-brick contain extra proportions
of silica.
Porcelain teeth are manufactured by processes sim-
ilar to those employed in making porcelain ware.
The 6o6/i/ consists chiefly of felspar, kaolin and silica
(Si02) ; the enamel, mainly of felspar. The differ-
ent shades of enamel are produced by fine division
of various metals, or of metallic oxides (purple of
cassius, for instance). A representation of a gold
filling may be obtained by applying a mixture of
precipitated gold, or auric chloride and chamomile
oil to the limited part desired on the surface of the
tooth, and heating. (See Gold.)
Materia Medica. Alum, alumen, possesses styp-
tic and astringent properties, condensing the tis-
sues by coagulating their albumen ; dried alum,
alumen exsiccatum, is mildly caustic. In large doses,
Aluminum. 181
taken internally, alum acts also as an emetic and
purgative.
Alum is employed locally to arrest alveolar
hemorrhage, and in solutions of varying strength,
in treatment of spongy gums, of congested mucous
membrane of mouth and throat, and for relieving
the inflammation and soreness, induced by wearing
artificial dentures, and as an injection in many
flowing diseases; and as a collyrium. Powdered
alum, added to Laharragues solution, makes an ef-
fective bleacher for discolored teeth.
Aluminum chloride., sulphate, and acetate, are dis-
ir>fectants and antiseptics. Very weak solutions of
either of these, will effectually neutralize offensive
breath, arising from catarrhal affections.
The chloride is sometimes used for bleaching
teeth.
Dose. Alum 0.65 — 1.00 Gm. (gr.x — xv).
Alum (dried), 0.25 — 0.65 Gm (gr.iv — x).
R. Aluminis, 4.00 Gm. (^i).
Tinctura myrrhse, 15.00 fGm. (f^ss).
Aq. Dest. q. s. ad. 60.00 fGm. (f^ij)
M. S. Apply to spongy gums.
Gallium, Indium, etc.,
Ga. In.
These metals are chemically related to aluminum.
They are extremely rare, only traces of tliem being
182 Inorganic Chemistry.
found in zinc blende. The atomic weight of Al is
27, of Ga 70, and of In 114, a regular gradation ;
the specific gravity of Al is 2.6, of Ga 5.9, and of
In 7.4, a regular gradation. Both gallium and in-
dium were discovered by spectrum analysis. Their
sulphates form ammonia alums.
Gallium, and the rare metal scandium., are of es-
pecial theoretical interest, on account of their ex-
istence and properties, having been predicted in
advance of their discovery.
Iron. 183
CHAPTER XIII.
IRON.
Symbol, At. Wt. Sp. Gr. Valency,
Fe. 56, 7.8. II, IV, VI.
Ever since the ante-historic times of Tubal Cain,
who was a worker in iron, this metal has held its
own as one of the most important substances in
nature.
It is abundantly distributed, although but a very
small quantity of native iron has been found ; a
large proportion of meteors consist of metallic
iron. Iron is a constituent of innumerable min-
erals, is present in all kinds of rocks, and soils, in
the waters of nearly all mineral springs, and in the
bodies of plants and animals.
The ores from which iron is obtained, however,
are practically very limited in number. These are,
chiefly, magnetic oxide (magnetite), Fe304 ; ferric
hydrate (limonite), 2Fe203 3H20; ferric oxide (he-
matite), Fe^Og ; and ferrous corbonate (siderite),
FeCOg. Those ores that are not native oxides,
are converted into artificial oxides by roasting, so
that practically, the chemical process of producing
184 Inorganic Chemist?^.
iron on a large scale consists essentially in reduc-
ing the oxide with carbon. Alternate layers of the
ore, fuel, and limestone are placed in the " high
furnace," and hot air forced upward through the
mass, producing such a high temperature that the
oxygen leaves the ore, and takes up with carbon,
leaving iron in the metallic state:
Fe203 + 3C = SCO + 2Fe.
The limestone serves as a flux in removing silica
and other impurities, which fuse into a "slag," and
remain on top of the molten iron. The process is
continuous, until the furnace wears out; the mate-
rials being added at the top and the melted slag
and iron drawn off at the bottom at regular inter-
vals. The metal is drawn off into molds, and is
known as cast or pig iron, and contains a good deal
of carbon^; this is burned off in a reverberating
furnace, together with sulphur, silicon, phosphorus,
and other impurities in the form of oxides. This
operation is known as '' puddling," the result being
wrought iron.
The different varieties of commercial iron con-
tain more or less carbon. Cast iron contains the
most carbon, 2 to 6 per cent. Steel considerably
less, 0.5 to 2 per cent, and wrought or malleable
iron, less than 0.5 per cent.
Wrought iron is fibrous in structure, and tough;
Iron. 185
at a high temperature it becomes pasty, in which
condition it is susceptible of welding.
The melting point of iron is very high, probably
above 2000° (3632F). It is malleable when hot,
and ductile, and possessed of superior tenacity ;
and when pure is white.
Iron is acted upon by hydrochloric, and sulphuric
and dilute nitric acids, and by the haloids; and
when heated, by phosphorus, sulphur, and oxygen.
It would be doing more than our requisite duty
to attempt to name the uses to which iron is ap-
plied in the arts; and w^ould be a work of superero-
gation also, to consider its numerous compounds in
their chemical relation to commerce, the arts, and
medicine.
Ferrous Salts, which may be regarded as derived
from ferrous oxide, FeO, are mostly pale green in
color.
Ferrous Sulphate, FeSo4,7Il2 0, commonly called
green vitriol, or copperas.
Ferrous Chloride, FeClg, and /errors iodide, Yel^,
are pale green, and soluble. Ferrous sulphide, FeS,
made by fusing iron and sulphur together, dissolves
in dilute acids, with evolution of II2S.
Ferrous Carbonate, FeCOg, a. white precipitate,
produced when solution of a ferrous salt, as FeSO^,
is added to a solution of an alkaline carbonate, as
16
186 Inorganic Chemistry.
ITagCOg, on exposure to the air, this ferrous car-
bonate decomposes into free CO 2, and Fe2 03 ; the
latter substance is known as "jeweler's rouge"
(polishing powder), and as the pigment, "Yenitian
red." All ferrous compounds are prone thus, to
take up oxygen from the air, and become changed
into ferric compounds, which are chiefly, either
red or yellow.
Ferric oxide, FcgOg, sesqui oxide of iron, may be
considered the basis of the ferric salts. The oxide
itself has been sufficiently described.
Ferric Chloride, Fe2Cl6, perchloride of iron, can
be prepared by dissolving ferric oxide in hydro-
chloric acid, or by direct action of CI on iron, or
by heating the hydrate in the presence of CI. It
consists of orange red, deliquescent crystals, of
strong styptic taste, and acid reaction, and very
soluble in water and alcohol.
Ferric hydrate, Fe2(H0)gf hydrated peroxide of
iron, is obtained as a reddish precipitate, when
either ferric chloride or ferric sulphate, in solution,
is added to solution of ammonia (or caustic alkalies).
It is the favorite antidote to arsenic ; should be
made fresh, washed in water, and given ad libitum..
Iron rust, is ferric hydrate.
Ferric sulphate, FeS2, iron pyrites, sometimes
iirt
Iron. 187
called '' fools gold/' is used in the manufacture of
copperas and of sulphuric acid.
Ferric sulphate, re2 (804)3, persulphate of iron,
prepared by boiling a solution of ferrous sulphate
and sulphuric acid, and adding nitric acid. On
evaporation it appears as a buff-colored mass,
slowly soluble in water. Practically, however, the
above solution is not evaporated; it is a clear
brownish-red liquid, of slight odor, very styptic,
and of somewhat sour acrid taste.
MonseVs solution, subsulphate of iron solution, an
oxy-sulphate, probably 2Fe2 03,(804) 3. The solu-
tion is prepared as above, except that only one-
half the amount of sulphuric acid is employed. It
is of a deep ruby red color, no odor, and of a very
astringent but not acrid taste. MonseVs powder of
the subsulphate, possesses the same properties as
the solution.
Magnetic iron oxide, FeO, Fe203, ferroso-ferric
oxide, is incidentally produced in the shops in the
form of " iron-scales."
Dyalized iron is essentially an aqueous solution
of the hydrate obtained from a mixture of ferric
chloride and ammonia ; the ammonium chloride
formed, passes through the dyalizer, leaving the iron
in a colloid state. It is inodorous ; of a non-styptic
taste, and considered by some a good chalybeate.
188 Inorganic Chemistry.
Iron by hydrogen, reduced iron, metallic iron in
fine powder, gray-black in color, produced by pass-
ing a stream of hydrogen over heated ferric oxide.
Materia Medica. — Salts of iron, combined with
vegetable astringents, form ink. They are, there-
fore, incompatible with tannin.
The per-(ferric) salts of iron have a decided local
influence in arresting passive hemorrhage, their
astringency causing contraction of the small ves-
sels; and by coagulating their albumen, a corru-
gating and hardening of the tissues.
Whenever it becomes advisable to use a hse-
mostatic after the extraction of teeth, either the
perchloride in semi- crystallized form, or in solution ;
or the liquor ferri chloride (ferric chloride crystals,
37.8 per cent, in water), or Monsels powder or solu-
tion may be selected for the purpose, and applied
with a prospect of more than average success. We
would not recommend these salts of iron, how-
ever, in gargles or washes for mouth or throat, \u-
asmuch as they undoubtedly corrode the teeth.
The principal indication for the internal exhibi-
tion of iron, is as a tonic in ancemia. Iron being
an essential constituent of the red corpuscles of the
blood, it not only augments the quantity of haemo-
globin, but increases the number of the red corpus-
cles as well ; furnishing thus, by an extra supply
Iron. 180
of healthy blood, fresh stimulus to the muscular
fibers of the heart. It tones up the mucous mem-
brane of the stomach, inducing improved appetite
and digestive power. It increases the temperature
by reason of its function of carrying oxygen to the
tissues.
190 Inorganic Chemistry,
CHAPTER XIV.
IKON — Continued.
The actual state in which iron exists in the red
corpuscles, and the exact relation it bears to the
operations in tissue waste, are not definitely known.
We may assume, however, with some degree of
safety, that when it takes up, in the lungs, the
oxygen, received from the air, by inhalation, the
chemical state, in which it passes through the arte-
rial circulation to the capillaries, is as ferric oxide
(FegOg). In the process of tissue waste, some, per-
haps many, of the molecules of this compound are
reduced to ferrous oxide (FeO), thereby setting free
nascent oxygen, which at once plays its part by
uniting with the carbon (and other elements also),
of the tissues, which union produces CO2. Now,
CO2 does not long remain free ; it finds the
reduced iron oxide, and they unite, producing fer-
rous carbonate, according to the simple equation,
FeO + Co,=:FeC03.
The ferrous carbonate, thus formed, is carried
through the venous circulation to the capillaries of
the lungs, where it suffers decomposition by the in-
Iron, 191
fluence of the inspired oxygen of the air; the CO2
es(;aping in the respiratory exhalation, while the
FeO takes up with the oxygen present, 2FeO-|-
0=Fe,03.
Sach, in brief, are probably the principal reac-
tions, involving iron, that occur throughout the
circulation. They afford us a fair idea of at least
two important functions performed by iron, namely,
the carrying of atmospheric oxj'gen from the lungs
to the capillaries, via the arterial circulation ; and
of the carbon dioxide, by way of the veins, from
the capillaries to the lungs.
A question of some import occurs in this con-
nection. Does the CO2, formed continuously in
every portion of the living animal body, have any
influence at the time of its development, in pre-
venting the oxygen of reserve from a too active par-
ticipation in the oxidation of the tissues? And
does its presoncie, while yet free, previous to its
union with FeO, tend to keep the normal process
of oxidation of tissues from being painfully mani-
ifest to our consciousness, by governing, with just
the exact amount of pressure required, the con-
ductivity of the peripheral extremities of the sen-
sory nerves, or by primary influence, through the
same direct means, on the receptive centers of the
brain itself?
192 fnorganic Chemistry.
If CO., is possessed of the attributes indicated,
then any increase for the time being, in the amount
produced, or any means that will prevent, even
temporarily, the regularity of its removal from the
body, will induce a corresponding reduction in our
perception of pain. Rapid breathing, " holding the
breath," experimentally, or as we do instinctively,
while awaiting a shock, violent exercise, and men-
tal excitement, are all productive of either an in-
crease in the quantity of CO 2, or of its temporary
retention throughout the tissues ; and w^e all recog-
nize, as a fact, that the above means are effective
for the time being, in lessening our susceptibility
to pain. Cause and effect seem, in these instances,
to agree.
Physical causes — molecular physics — although
they may not be appreciable to our senses, are in-
volved in all forms, plus or minus^ of nervous or
mental phenomena, including the so-called hyp-
notic influence ; but in explaining the physiological
action of certain drugs, we are frequently com-
pelled to dismiss the subject by saying, " they have
a direct effect on the nervous system," or some par-
ticular set of nerves. .
In all experiments with nitrous oxide, it has
been found to be active only as a carrier of oxy-
gen. Combustibles burn in it with more energ^^
Iron. 193
than in the air, the heat setting the oxygen free,
oxide compounds only resulting. It has also been
ascertained, that when inhaled, ^2^ dissolves in
the arterial blood, unchanged. In this way it
supersedes the legitimate carrier of oxygen, Fe^Og,
and the latter compound, not being allowed to de-
compose, in the capillaries, into ferrous oxide, FeO,
the CO2 that is formed, in much greater abun-
dance than usual, by the oxygen of the N2O, can
not escape in the usual way, as ferrous carbonate;
much ot it, comparatively, remains free, for the
time being, causing at first, the pleasurable excite-
ment, exaltation of the faculties, hallucination,
anoesthesia, and finally a state of carbon dioxide as-
phyxiation, which are observed to take place when
^2^ ^^ inhaled.
Nitrous oxide is, therefore, not an asphyxiating
agent per se. It so acts indirectly, only when
pushed to the extent of developing and accumu-
lating CO2, in quantity necessary for the purpose,
the danger line moving to and fro, according to
the individual. The relative immunity from danger,
with N2O as an anaesthetic, may be accounted for
by the exaggerated oxidation of carbon (a natural
process), which immediately ensues ; and the rapid
escape of the active compound, CO2, as soon as
air is admitted, which at once restores to iron the
17
194 Inorganic Chemistry,
opportunity of performing its accustomed duties
in the circulation.
MANGANESE.
Symbol, At. Wt. Sp. Gr. Valency,
Mn. 54. 8. II,IV,VL
Manganese is closely related to iron. It occurs
somewhat abundantly, mainly as an oxide, Mn02,
which ore, when ground, is known as the black
oxide of manganese.
The metal is chiefly obtained from the black ox-
ide, by reduction with carbon. It is gray-white,
lusterless, resembling cast iron, brittle and very
hard, very difficult to melt, and decomposes water^
setting hydrogen free. With copper it forms a
beautiful alloy.
Four well defined oxides, MnO, Mn02, Mn203,
and Mn3 04, are known. The first is strongly ba-
sic, the third is weakly basic, forming, with acids,
typical salts, and with basic oxides it acts as acid,
forming salts called manganites. The second and
fourth oxides are neutral.
Hydrogen permanganate, H2Mn208, permanganic
acid, produced by distilling potassium perman-
ganate with sulphuric acid, is a most powerful
oxidizer, setting fire to alcohol, paper, etc. Its
most characteristic salt is potassium permanganate,
Cobalt, Nickel. 195
K2Mn208, prepared by mixing manganese dioxide,
potassium chlorate and potassium hydrate in a
Httle water, evaporating and heating to red heat.
It presents, as dark violet crystals, soluble in water,
the dilute solution, exhibiting a superb purple color.
It readily parts with its oxygen in the presence of
organic matter, as alluded to under potassium.
COBALT, NICKEL.
Co. Ni.
Both cobalt and nickel are closely related to
iron, but are comparatively rare. The atomic
weight of cobalt is 59, of nickel, 58, and of iron,
56. The specific gravities of these three metals
are also about the same, and their valency is the
same.
Cobalt occurs in nature as a sulphide, C03S4 ;
as an arsenide, CogAsg ; as an arsenate, C03
(As04)28H20; as speiss-cobalt, Col^iFeAsg ; and
as cobalt-glance, CoFe (AsS)2. Many of the com-
pounds of cobalt are used as pigments and for col-
oring porcelain and glass. A solution of cobalt-
ous chloride, C0CI2, in water, furnishes sympa-
thetic ink of a blue color, when heated, but which
becomes invisible on cooling, by absorption of
moisture.
XiCKEL' is always a constituent of meteoric iron.
106 Inorganic Chemistry.
Its chief sources are, as the arsenide, kupfernickel,
a yellow ore, whence its name ; and as sulphides
and silicates of nickel. The metal is used some-
what extensively for coating other metals by elec-
trolysis, the electrolyte employed being the double
sulphate of nickel and ammonium (^"£[4) 2 ^1(804)2,
6H2O, dissolved in water. The lower salts of
nickel are generally green. An alloy of nickel
and copper is the familiar instance of the " nickel."
German silver is nickel, copper, and zinc.
Like iron, both cobalt and nickel are magnetic.
They are also malleable and ductile, and occupy
the first rank in tenacity, like iron, and are affected
by acids similarly to iron. The color of cobalt is
reddish-white.
Arsenic. 197
CHAPTER XY.
ARSENIC.
Symbol, At. Wt. Sp. G-r. Valency,
As. 75. 5.7. III-V.
Elementary arsenic is inert, but its soluble com-
pounds are extremely poisonous. It is found free,
and in a great many minerals, in company with
sulphur, iron, cobalt, nickel, etc., as sulphides, ar-
senides, arsenites, and arsenates. It is chiefly ob-
tained, however, from arseno-pyrites, a sulphide of
iron and arsenic, by sublimation, the arsenic being
volatile. Its vapor has an odor of garlic, by which
its presence may be indicated, when heated by the
blow pipe. Like phosphorus, its molecule con-
sists of four atoms, T^^y inasmuch as its va-
A.S .A.8,
por density is 150. Arsenic is a dark-gray, brittle
solid, metallic in appearance; classed by some as a
non-metal, by others as a metal ; it is about mid-
way, in chemical properties, between these two
classes of elements. About the only purpose for
which metallic arsenic is used, is for hardening
lead ^' shot." A very impure variety is sold as a
198 Inorganic Chemistry.
fly-poison, under the erroneous name of " cobalt."
"Marsh's test" for arsenic, consists in the devel-
opment of " nascent" hydrogen, in the presence of
the suspected mixture. Pure zinc and dilute hy-
drochloric acid will accomplish this, and if arsenic
is present, it will escape as ursine, AsHg, an exceed-
ingly poisonous gas, one bubble of which proved
fatal to its discoverer, Gehlen. This gas, as it es-
capes from a jet, arranged with proper precaution,
when kindled, will deposit a mirror-like stain of
metallic, As on a cold, clean surface of porcelain,
held in the flame. Antimony compounds will give
similar results, forming SbHg, but the deposited
arsenic is soluble in sodium hypochlorite solution,
whereas the antimony is not. It is said that 5-0V0
of a grain of arsenic can be detected in this way.
Two oxides of arsenic, and their corresponding
acids are known.
AS2O3 + 3H2O = 2H3ASO3
Arsenous Water. Arsenous
Oxide. Acid.
AS2O5 + 3H2O = 2H3ASO4
Arsenic Arsenic
Oxide. Acid.
Arsenic compounds are not so poisonous as the
arsenous, and not so important.
Arsenous oxide, AS2O, exhibits such momentous
qualities, that it has appropriated the very name of
arsenic^ and is generally known as such. It is
Arsenic, . 199
formed by roasting arsenical ores in air, collecting
the vapors and resubliming; it exists in two varie-
ties, one crystalline, and the other in lumps, re-
sembling porcelain; the latter is the usual com-
mercial variety, the powder being white and heavy,
of a gritty feel, tasteless, and odorless, and un-
changed in air. It is slowly soluble in water, giv-
ing rise to arsenous acid, whose salts are known as
arsenites. The arsenites of the alkali metals are
soluble in water; the arsenites of iron and mag-
nesium not so, hence the employment of iron and
magnesium hydrates, as antidotes. Sodium ar-
senite NagAs, as a mordant is used in calico print-
ing; and the brilliant pigment, Paris-green, a
double salt of copper arsenite and copper acetate,
Cu3Aa2 Cu (0211302)2 is extensively used for col-
oring wall-papers. Whenever such paper gives a
green color to flame, or changes from green to blue,
by a drop of aqua ammonia, the presence of ar-
senic may be suspected.
Dissolved^ in acids, arsenous oxide forms salts,
typical of the acid; as, for instance, from hydro-
chloric acid solution, arsenous chloride, AsOlg, is
obtained.
The 2 sulphides of arsenic, AS2S2, As^Sg, are
known as the minerals, red realgar, and golden-yel-
low orpimenl, respectively.
200 Inorganic Chemistry.
Materea Medica. — The official name of arsenous
oxide, AS2O3, is Acidum Arsenosum, but it is com-
monly spoken and written of as arsenic; also, as
arsenous anhydride, arsenious acid, white oxide of
arsenic, white arsenic, arseniosum oxidum, and
ratsbane; in its medicinal consideration, we shall
follow the custom, and call it arsenic.
When applied locally, arsenic acts as a severe
caustic irritant, inducing redness and excessive in-
flammation of the part, followed by suppuration
and sloughing; for this reason, it is used some-
times, as a cancer cure. In the operation of devi-
talizing exposed dental pulps, it is the Samson
upon which nearly all dentists confidently rely.
The amount of arsenic necessary to destroy the
life of the pulp need never exceed the ordinary
internal dose. It is usually mixed with some prep-
aration of morphine, or cocaine, of which mixture
a paste with either creosote, carbolic acid, or oil of
cloves, etc., is made and applied to the pulp, and
sealed with gutta-percha, or cotton dipped in either
sandorac varnish, or in a ssturated solution of aris-
tol in chloroform.
A suggestive method that might decrease the
period of pain, would be to apply a trace of pow-
dered cocaine hydrochloride, say for five minutes,
before inserting a paste, made of arsenic and solid
Arsenic. 201
caustic potash. Sometimes tannin alone, or in
glycerine, is employed as an adjuvans to arsenic,
on account of astringent properties. In all cases
care must be observed, lest a part of the arsenic
escape to the surrounding parts, inasmuch as the
ar^senic bum is painful and slow to cure, and the al-
veolar process itself might be, to a limited extent,
completely destroyed. Certain individuals are
peculiarly susceptible to the injurious effects of
arsenic, and these do not suffer in having pulps
devitalized, as do those who have strong resisting
power against the action of the drug.
Taken internally in small doses, arsenic acts as a
tonic, and antiperiodic, increasing appetite and
digestion, producing a rotund form, and fair skin ;
increasing the secretions of the primce vice, exsdtmg
the mental faculties and stimulating the heart's
action, and respiratory power. It is recommended
in treatment of ague, neuralgia, asthma, dyspepsia,
chronic skin affections, etc. When its use is con-
tinued for some time, it usually causes oedema of
the eyelids, ptyalism, disordered systemic condition,
and eruptions of the skin. The arsenic eaters of
Styria observe the precaution of not taking water
into the stomach at the same time they partake of
the drug, so that its slow absorption, and probably,
rapid elimination follow. Toxic doses produce gas-
202 Inorganic Chemistry.
tro-enteritis, vomiting, diarrhoea, etc. In chronic
poisoning, there is in addition, a fatty degeneration
of the muscles and heart, and parenchymatous de-
generation of the liver and kidneys.
Arsenic is usually given in the form of Fowler's
Solution, Liquor potassii arsenitis, prepared by boil-
ing together arsenous oxide and potassium bicar-
bonate in water, to which the compound tincture
of lavender is added. This preparation may be
taken in water, always after meals, full doses at
first, gradually diminishing as the treatment pro-
ceeds.
Antidote. — Emetics (zinc sulphate), followed by
freshly prepared hydrated iron (see Iron), and cas-
tor oil.
Dose. — Liquor Potassii Arsenitis, 0.10-0.30 fGm.(TTL ij-v).
Acidum Arsenosura, 0.001-0.006 Gm. (gr. -^\, j\).
R. Acidi Arseniosi, 8.00 Gm (^ij).
CocaiDi Hydrochloris, 2.00 Gm. (^ss).
M. S. For office use.
To prepare for devitalizing pulp, make a paste
with caustic potash and carbolic acid. (Robinson's
Remedy.)
Antimony.
Symbol, At. Wt. Sp. Gr. Valency,
Sb. 120 6.7 III— Y.
Antimony is not an abundant metal, although
Arsenic. 203
I'omparatively inexpensive. It exists in nature free,
and as an oxide, a sulphide, and with silver and sul-
phur. The metal may be obtained by heating its
sulphide with iron, Sb2S3+Fe3=3FeS + 2Sb ; or
hy roasting its sulphide, it is converted into an
oxide, which is reduced by carbon.
Antimony is a blue-white solid, hard and very
brittle ; does not tarnish in the air, but takes tire
at a red heat ; is soluble in nitric acid, and forms
synthetic binary compounds, with chlorine, oxy-
gen, bromine and iodine. Zinc precipitates anti-
mony from its solutions, as a black powder, which
is used for giving plaster casts the appearance of
steel. The metal melts at 450 (840F). A curious
allotropic variety is obtained by electrolysis, w^hich
is explosive when hammered or heated. The chief
use of the metal is in giving hardness to alloys-
Typemetal is an alloy of antimony, lead, and tin ;
Britannia metal, of antimony and tin : and Babbit's
anti-friction metal, useful for dies, is composed of
antimony, lead, tin, and copper.
Antimony forms three oxides Sb203, Sb2 04,
Sb2 05. The trioxide and pentoxide, like those of
nitrogen are acid oxides, but their acids HSb02,
IlSb03, unlike those of nitrogen, are very weak.
There is also an ortho-antimonic acid, H^SbOg,
and an ortho-antimonous acid, IlgSbOg.
204 Inorganic Chemistry.
Antimony and potassium tartrate, is a salt known
as " tartar-emetic."
Antimonous chloride, SbClg, is the " butter of
antimony," which is changed by water, into an
oxychloride, SbClg -f H2O = 2HC1 + SbOCl.
Antimony oxysulphide, Sb2 02S2, imparts a yel-
low tint to glass and porcelain. The nature of
HgSb was sufficently indicated in the preceding
chapter.
i
Bismuth. 205
CHAPTER XVL
BISMUTH.
Symbol, At. Wt. Sp. Gr. Valency,
Bi. 208. 9.80. III-V.
Bismuth, like antimony, belongs to the same
class with arsenic. It is principally found native,
and is obtained by simply melting out the metal
from adherent rocky matter and collecting in suit-
able molds. It is comparatively rare, and besides
its native condition, is found in only a few min-
erals, as an oxide, a sulphide, a sulpho-telluride,
and a carbonate.
It is a brilliant reddish- white, hard brittle metal;
crystallizes in rhombohedroiis, which, on account
of slight tarnishing in the air, present an iridescent
appearance. It is acted on readily by nitric and
nitro-hydrochloric acids, and by chlorine, but not
by hydrochloric or cold sulphuric acids. It melts
at 264° (507°F), and in solidifying, expands 3^ of
its bulk, making a sharply defined cast when
poured into a mold.
Bifemnth is important chiefly as a constituent of
fusible alloys, one of which was described in a pre-
206 Inorganic Chemistry.
vious chapter. Another is composed of 3 parts
of cadmium, 4 of tin, 8 of ead, and 15 of bismuth,
which melts as low as 60° (140°F); and another,
which melts at 82° (180°F), is composed of 1 of
cadmium, 6 of lead, and 7 of bismuth. Other al-
loys, of the above kind, serve as safety plugs for
steam boilers, vulcanizers, etc.
In most of its compounds bismuth acts as atriva-
lent base, such as the chloride, BiClg ; the oxide,
Bi.^Og ; the sulphate, 312(804)3, and the nitrate,
Bi(!N'03)3. When water is added in excess to a
solution of a bismuth salt, the bismuth, salt decom-
poses, a basic salt being precipitated.
The formation of bismuth sub-nitrate, HgBiOg
NO 3, by dissolving bismuth in nitric acid, depends
on this principle, although the process itself is
rather complicated.
When water is added to bismuth chloride,
BiCl3, a white precipitate of bismuth oxycloride
results. BiClg + H2O = 2HC1 -f BiOCl. This
latter substance is a white soft bulky powder, re-
sembling the sub-nitrate, and is used as a "face
powder." The following equation, BiClg +
3K0H = 3KCI + Bi(OH) 3, shows the formation
of bismuth hydrate, a precipitate which, on drying,
loses water, and becomes an amorphous white
flocculent powder, less unwholesome to the skin
Bismuth, Vanadium and Tantalum. 207
than tlie oxychloride. This hydrated oxide, BiO(HO),
is basic to strong acids, as sulpliuric, etc., and
acid to strong bases , as sodium, etc.; for example,
NaBiO^, sodium bismuthate.
Materia Medica. — Bismuthi sub-nitras is em-
ployed locally, in powder, alone, or with charcoal,
in eancrum oris, and other forms of ulceration
of the mouth, in intertrigo, and as a snutf in inflam-
mation of Schneiderian membrane, etc. It possesses
astringent, sedative, and antiseptic properties, in
virtue of which, it probably acts internally in re-
lieving gastric pains, vomiting, and diarrhoea.
Dose.— 0.50— 1.00 Gm. (gr. viij— xv.)
Vanadium.
Symbol, At. Wt. Sp. Gr. Valency,
V. 51. 3.6. V.
Vanadium is an extremely rare substance ; it oc-
curs in small quantity in some iron, lead, and cop-
per ores, and is a non- volatile gray- white powder.
It forms 5 oxides corresponding to those of nitro-
gen, VjO, V,O„V,0„ V,0„ and Y,0,. Vana-
dium compounds have very little practical import-
ance.
Tantalum and Niobium.
Ta. At. Wt. Nb. Valency,
182. 94. V.
These so-called metals are very rare. Both are
208 Inorganic Chemistry.
are black powders. They form acid oxides. W\o-
bium is also known by the better name, Columhium.
Molybdenum, Tungsten.
Symbol, At. Wt. Sp. Gr. Valency,
Mo. 96 8.6 VI.
Molybdenum is another rare element, occurring
in small quantity, as a sulphide, M0S2, and as lead
molybdenate. It is a white, brittle metal, almost ab-
solutely infusible. When heated in air, it oxidizes
to molyhdic oxide, M0O3, analogous to sulphuric
oxide, SO3; molyhdic aci<i, H.^MoO^, is analogous
to sulphhuric acid, H2SO4. Some of the molybde-
num compounds are indispensable reagents.
Tungsten.
Symbol, At. Wt. Sp. Gr. Valency,
W (Wolfram), 184. 19.26. VI.
Tungsten is not abundant, but more so than
molybdenum. It is found as ferrous tungstate,
FeW04, in the mineral ivolfram, and as calcium
tungstate, and lead tungstate. It is a white metal,
hard and brittle, and very heavy, hence its name,
signifying heavy stone; it is difficult to fuse, and
when heated to redness takes fire, and produces
tungstic oxide, WO3. A small addition of tungs-
ten to steel, is said to confer on the latter, extraor-
dinarv hardness and fineness.
Uranium. 209
The oxide, WO3, is an acid oxide, the corre-
sponding acid having the formula, H2WO4. The
tungstate of the alkali metals (more especially of
sodium, NagWO^), are sometimes used as mor-
dants, and for rendering light cloth fabrics unin-
flammable.
Uranium.
Symbol, At. Wt. Sp. Gr. Valency,
U. 2.39. 18.68. VI.
Uranium is another rare metal, existing in only
a few minerals ; it is found mainly in the form of an
oxide.
When fused, which is difficult to accomplish, it
is a white malleable metal, permanent in air, but
if pulverized, and heated to about 200° (392F), it
takes fire, and burns with great splendor, produc-
ing a green oxide. It also shows great energy in
uniting with chlorine and sulphur.
Uranium forms several oxides, which are basic
in the presence of strong acids, and acid in the
presence of strong bases, like those of tungsten.
It is quadrivalent in tlie uranous compounds, as
UCI4, UO2, U(S04)2, etc., and sexvalent in the
uranic compounds. In the uranic salts the bivalent
radical uranyl, UO2, is supposed to be the electro-
positive radical, as in uranic oxide (uranyl oxide),
(U0,)0; also (U0,)C1„ (UO,),2X03), (UO,)SO,).
18
210 Inorganic Chemistry.
There is no uranic chloride (UClg), or bromide, etc.,
as with tungsten.
Alkaline bases form salts with uranic oxide,
UO3, known as uranates ; thus. Sodium Uran-
ate, Na2 0, 2UO3, and Ammonium Uranate,
Am20,2U03, which are known as " uranium yel-
low," are used in coloring porcelain and glass, con-
ferring a green-yellow color.
Chromium.
Symbol, At. Wt. Sp. Gr. Valency,
Cr. 52. 6.81. YL
Chromium occurs somewhat more abundantly
than the other metals of the chromium group. It
occurs as lead chromate, and also in small propor-
tion in several minerals, but is obtained usually
from ferrous chromite, FeCr2 04.
Chromium, obtained by reducing its oxide by
carbon, exhibits as a very hard, steel-gray mass,
practically infusible ; obtained by reducing the
chloride by zinc, it occurs as a glistening gray-
green powder, showing minute tetragonal octahe-
drons. It is unaffected in air, but burns, when
heated in oxygen. It has been found in meteoric
iron. It is readily acted upon by dilute hydro-
chloric acid, less so by dilute sulphuric acid, and
not at all by concentrated nitric acid. The metal
itself is of no practical use, but its compounds are
Chromium. 211
both numerous and important; they are nearly all
brilliant in colors, whence the name of the element,
taken from a Greek word, signifying color,
Chromous chloride, CrCl2, is one of the most
powerful reducing agents known. It precipitates
gold from solution of auric chloride.
Chromic Chlroide, Cr2Clg, occurs in crystal-
line plates of a pale violet color. Its hydrate,
Cr2Clg9H20, is a dark green.
Chromous oxide, CrO, is a strong base, forming
salts of a pale blue, but unstable, as they rapidly
absorb oxygen from the air.
Chromic oxide, sesquioxide, Crg-Og, is a bright
green powder. It is used in giving a green color
to porcelain and glass, and to modify the yellow of
titanium oxide in porcelain teeth. The emerald
owes its color to this compound. It is basic or acid,
according to the presence of acid or basic radicals.
Chromium trioxide, CrOg, may be obtained in
superb crimson needles, by adding strong sulphuric
acid carefully to a saturated aqueous solution of
potassium bichromate, allowing the mixture to
cool, and drying on a porous tile. It is a powerful
oxidizing substance. A drop of alcohol coming
in contact with the dry crystal, will ignite by the
heat of the oxidation.
212 Inorganic Chemistry.
Chromic trioxide is the typical acid oxide of
chromic acid and the chromates.
CrO^ + H2O = H2Cr04
(Chromic Acid.)
With potassium, for example, it forms the normal
salt, K2Cr04, and by addition to this, of one more
molecule of CrOg, we have potassium pyrochro-
mate or dichroraate.
K^OrOg + CrOg = K2Cr207.
This salt is better known as hi-chromate of potash.
It occurs iu splendid orange-red crystals, and is
employed in the arts for various purposes; in pre-
paring the chromium paints, in dying, in calico
printing, and in photography. Gelatin containing
the salt, remains insoluble wherever acted on by
light, but is soluble in other portions : the photo-
graph taken on such a film of gelatin stands out
in bold relief, and can be copied in electrotype.
This salt is also used in certain galvanic battery
solutions.
By adding two molecules of 2(Cr03) to K2Cr04,
we have K2Cr30iQ.
Plumbum chromate, PbCr04, is "chrome yel-
low," which, by boiling with caustic alkali is con-
verted into PbCr04,PbO, "chrome red;" and
" chrome orange " is a mixture of these, the orange
ray being intermediate between yellow and red.
Chromium. 2lS
Materia Medica. — Chromic acid is one of the
most energetic disinfectants, in virtue of oxidizing
power. It should not be mixed with organic sub-
stances. As an escharotic it penetrates deeply, and
wlienever used in the mouth, in treatment of phag-
edsenic ulcers, etc., it should be in suitable dilu-
tion, and very carefully applied.
214 Inorganic Chemistry.
CHAPTER XVII.
GOLD, ETC.
Symbol, At. Wt. Sp. Gr. Valency,
Au. 96.5. 19-4. I-III.
Gold, aurum ; the alchemistic " Rex Metallo-
rum," has held its supremacy among the metals
from the earliest historic times. It occurs native,
and though very widely diffused, is not found in
" paying " quantities outside of a few limited sec-
tions, as in Australia, and the gold fields of the
United States.
The association of gold in nature, is generally
with quartz, iron oxide, in the debris or alluvial
deposits of such rocks, and in the sands of various
rivers. The only exception to its otherwise uni-
versal existence in the metallic state, is as a tellu-
ride, which also contains silver and other tellurides.
Alluvial gold is obtained by washing, which sepa-
rates the metal from the earthy matter. When a
veinstone is worked for gold, it is crushed to pow-
der, and if it contains pyrites, it is roasted; it is
then agitated with mercury, which takes up the
gold by amalgamation. The mercury is separated
Gold, 215
from the gold by pressure and distillation, and is
recovered for future use. If traces of base metals
are present, the gold is refined by passing chlorine
gas through the melted metal. By quartatioriy it
is separated from silver; the operation consisting
of adding silver to the bullion, until the latter is
made up of three parts of silver and one of gold.
The alloy is rolled into thin ribbon, and then the
silver in it dissolved out by nitric acid.
Gold possesses considerable tenacity, and ranks
first* in malleability and ductility; it is soft, and
crystallizes in isometric forms; its color is brilliant
orange-yellow, by reflected light; and when beaten
into very thin leaves, shows a bright green, by
transmitted light. It melts at about 1100° (2012F.)
Gold is always alloyed with other metals, to give
it the required hardness for practical use in the
arts, except in the case of preparations of gold for
filling cavities in teeth, wherein absolute purity is
desirable.
Pure gold is 24 carats fine. The mint alloy of
the United States is 22 carats ; that is, 9 parts of
gold and 1 part of copper. Jewelers' gold is of a
less carat, ranging downward from 18 to 12 carats.
Copper confers a ruddy tint to the alloy, and silver
a paler color. Platinum, or palladium, like Ag.,
glvee to gold a lighter shade ; the alloy, with small
216 Inorganic Chemistry.
proportions of platinum, is hard and elastic; with
palladium, hard and brittle. Traces of such metals
as antimony, tin, arsenic, bismuth, lead, etc., im-
pair the malleability and ductility of gold, and
render it intractable.
Dentists' gold foil, presumed to approximate 24
carats, is obtained by successive annealings and
hammering of the ingot, until thin enough to pass
between the rollers of a flatting mill. The thin
ribbons of gold thus prepared are cut into small
squares, and these are piled in considerable num-
ber between pieces of vellum and parchment, and
beaten; again cut into squares, and beaten; and
finally hammered between " gold beater's " skins,
until the required foil number is obtained.
Gold is practically unalFected by the air, sulphur-
retted hydrogen, the alkalies, or any single acid,
except, slightly, by selenic acid. It yields readily,
however, to nascent chlorine, a gentle heat favor-
ing the rapidity of the combination.
The chlorine for the purpose, is usually produced
by mixing 3 parts of hydrochloric acid with 1 part
of nitric acid, the mixture being known as aqua
regia, alluded to in a previous chapter.
To obtain free gold from its alloy with copper,
and silver, or other metals, or either one alone, dis-
Gold. 217
solve the alloy in aqua regia, facilitated by a gentle
heat. The reaction will be as follows:
12HC1 + 4IIXO3 = 8H^0 + 4N0C1 + 8C1.
6C1 -I- Au + Cu + Ag == AuClg + CuCl^ + AgCl.
The silver chloride falls down as a white curdy
precipitate, and the chlorides of gold and copper
remain in solution; it now remains to precipitate
the gold, and leave the copper in solution. This is
accomplished by various reagents, of which, two
only need be mentioned, namely, solutions of fer-
rous sulphate (copperas), and oxalic acid. The
ferrous sulphate is changed into ferric compounds,
and the oxalic acid into carbon dioxide, and hydro-
chloric acid, thus :
6FeS04 + 2AUCI3 = 2Fe2(S04), + Fe2Cl6 + 2Au.
or,
3H2C2O4 + 2AUCI5 = 6CO2 -f 6HC1 + 2Au.
Oxalic Acid.
The gold precipitated by the ferrous sulphate,
occurs as a dirty-looking brown powder; that by
oxalic acid, as spongy or crystalline. The precipi-
tate is washed, placed in a crucible lined with
borax, melted, and poured into proper ingot.
Scraps, filings, and sweepings of gold alloys con-
taining more or less of baser metals, as zinc, tin, lead,
antimony, bismuth, iron, etc., are often refined by
the dry method or roasting process, which consists
of adding to the heated mass, either oxidizing,
19
218 Inorganic Chemistry.
chloridizing, or sulphidizing substances. lN"iter,
(KNO3), is rich in oxygen, which it readily gives
up when heated. It is, therefore, the substance
usually employed as the oxidizer, and to whose
power all the baser metals named, except tin,
cheerfully submit. The latter metal, however, is
easily chloridized by heating with mercuric chlo-
ride (HgCl^). When sulphur is needed in the pro
cess, it is furnished by the crude antimonium sul-
phide (Sb2!S3). The disengaged sulphur forms sul-
phides of the base metals present; the antimony
alloys with the gold, and is afterward driven olf
from the latter, by heating in an excess of air.
The chemical compounds of gold are neither nu-
merous nor important.
Auric chloride^ AuClg, resulting by dissolving
gold in aqua regia and evaporating the solution
over the water bath, occurs as deliquescent, dark
red crystals, soluble in water, ether, and alcohol ;
of a styptic taste and escharotic and disinfectant
properties, the latter effect being due to the ease
with which it decomposes. It forms yellow double
chlorides, with the chlorides of sodium, potassium
and ammonium, asE^aCl, AuClg, called sodio-chlor-
aurate.
Aurous chloride, AuCl, is obtained as a yellow-
white substance, by heating evaporated auric chlo-
Gold, 219
ride. It is insoluble in water, and tends to change
to free gold and auric chloride.
Auric oxide, AU2O3, is produced by digesting
magnesia, MgO, in auric chloride. The magne-
sium aurate that is formed, is decomposed by nitric
acid, and on drying the residue, auric oxide is found
aa a dark brown powder, easily decomposed by
light and heat. It acts generally as an acid oxide,
uniting with bases to form aurates thus
K2O + AU2O3 =: 2KAUO2
Potassium Aurate.
Ammonium aurate, obtained by digesting auric
oxide in ammonia, is known as fulminating gold,
a dangerous explosive, ^H^, AUO2.
Aurous oxit/e, Au 2 0, is a greenish powder. Pur-
ple of Cassiush probably a compound of this oxide,
with the tw^o oxides of tin, obtained by reaction
between auric chloride and the two chlorides of
tin, produced by dissolving gold and tin in aqua
regia, and adding a weak solution of tin in hydro-
chloric acid. Chloridation and oxidation of both
metals take place successively. " Purple of Cas-
sius " (Au20Sn305), as before mentioned, is used
in coloring porcelain.
Materia Medica. — The mono-(aurous) chloride
is not used in medicine. The tri-(auric) chloride
is sometimes employed in obtunding sensitive den-
tine dissolved in ether or alcohol. It acts like the
220 Inorganic Chemistry.
chloride of zinc, by dehydrating the gelatinous con-
stituent of the dentine.
For internal administration the trichloride is
usually combined with sodium chloride. It pro-
duces an exhilarating influence on the nervous sys-
tem, and is useful in hypochondriasis, functional
impotence, etc., and in treating syphilis, as a sub-
stitute for corrosive sublimate. Its antidote is the
same as for the latter drug. The so-called bi-ch\o-
ride of gold cure mixture for alcoholism and the
opium habit, is said to contain no gold whatever,
and is not regarded as belonging to legitimate
therapeutics.
Dose. Auric chloride, 0.001-0.003 Gm. (gr. q\-2\)-
Professor Grant Molyneux, of Cincinnati, has
recently succeeded in developing a process of gild-
ing porcelain teeth with gold, to represent fillings,
facings, etc. The process consists essentially of
compounding neutral auric chloride (AuClg), with
Venice turpentine, and thinning the mixture with
Artist's Dresden " thick oil," to the proper consist-
ency. This is spread in desired position on the
porcelain, and allowed to dry slowly over a water
bath. It is then subjected to a red heat and, on
cooling, leaves a pure gold surface, susceptible of
a fine polish.
• A similar process with neutral platinic chloride,
Gold, Platinum. 221
(PtCl^), instead of gold solution, has been found
by Professor M. to be effective in forming a surface
of platmum, as a successful backing on porcelain
teeth, to which gold can be soldered without the
usual intervention of platinum pins, making an
attachment thus, as strong as the porcelain itself.
PLATINUM.
Symbol, At. Wt. Sp. Gr. Valency,
Pt. 197. 21.5. II-IY.
Platinum, originally found in South America, is
now principally supplied from the Ural Mountains
and, to some extent, from Borneo and California.
It always occurs in the metallic state, in little
grains or lumps, generally alloyed with gold, cop-
per, and iron ; and its natural congeners of the
platinum group, such as iridium, osmium, etc.
The methods employed for separating pure plat-
inum from its ores are complicated. It is a blue-
white metal, less brilliant than silver; not affected
by the air, nor by any single acid. It combines
directly with sulphur, silicon, arsenic, phosphorus,
and chlorine ; is acted upon by fused caustic hy-
drates, and dissolves slowly in aqua regia. It is
malleable and ductile ; is possessed of considerable
tenacity ; is about as hard as copper, expands uni-
formly with glass or porcelain, and is relatively a
222 Liorganic Chemistry.
poor conductor of heat and electricity : it melts at
the temperature of the oxyhydrogen flame.
On account of its infusibility, and insolubility in
acids, platinum is used in various forms in the
chemical laboratory, such as dishes, crucibles, stills,
foils, wire, blow-pipe tips, etc.; also in the construc-
tion of incandescent electric light lamps, as the neg-
ative element in Grove's galvanic battery, as sustain-
ing pins in porcelain teeth, as a basis for continuous
gum plates, and in combination with felspar, in
giving a required shade to enamel. In the form of
platinum-foil, sponge, or better ^i\\\,j)latinum black,
it possesses, in a high degree, the power of con-
densing gases on its surface, the latter being able
to condense 800 times its own volume of oxygen.
Platinum compounds are numerous and some-
what interesting.
Platinic Chloride, PtCl4, is formed whenever plat-
inum is dissolved in aqua regia; on evaporation
it shows as a deliquescent red-brown substance,
soluble it water, alcohol and ether ; it is used in
chemical analysis in detecting alkaloidal bases, as
'ptomaines, etc. It unites with the alkali chlorides
to form chloroplatinates, as 2KC1, PtCl4.
Platinous Chloride, PtCl2, is obtained when pla-
tinic chloride is heated gently, until chlorine ceases
to escape; it is a dark green powder, insoluble in
Iridium and Osmium. 223
water. It forms with alkali chlorides, chloroplati-
nites, as 2KC1, PtCl2.
Platinie oxide, PtOg, and platinous oxide, PtO,
and corresponding sulphides are known; also, a
remarkable series of compounds, formed by action
of ammonia upon platinum salts, called ammoni-
acal platinum compounds, as
p fNH3Cl
^^t^HgCl
Iridium and Osmium are heavier than platinum ;
the sp. gr. of Ir being 22, and of Os, 22.5. Their
atomic weights are near that of platinum, being
192.7 and 198.6 respectively. Iridium is not acted
on by the air, nor is it soluble in aqua regia. It re-
sembles polished steel, is brittle and very hard, and
is often alloyed with platinum, in the form of wire
and posts, for crown and bridge work.
The remaining congeners of platinum are Palla-
dium, Rhodium, and Ruthenium ; their sp. gr. are
respectively 11.4, 12, and 11.4; their atomic weights
are 106, 104, and 103. They are of little relative
importance. Palladium has the property of ab-
sorbing hydrogen ; the latter thus, is said to be
occluded.
224 Inorganic Chemistry.
CHAPTER XVIII.
ELECTROLYSIS.
Any compound liquid, capable of conducting the
electric current, is an electrolyte, and will suffer de-
composition by an electric current, in direct pro-
portion to its conducting power.
One of the sources of electric development is by
chemical action, and an arrangement by which the
force is utilized thus, is called a galvanic, or voltaic
battery. Galvanic batteries are constructed of vari-
ous substances, and in various forms : one principle,
however, obtains in all, viz., unequal chemical ac-
tion on conductors, in the exciting liquid. The
simplest conception of a galvanic battery, may con-
sider its construction as consisting of the metals,
zinc and copper, immersed in dilute sulphuric
acid; the zinc and copper are acted upon une-
qually by the acid, zinc more than copper; zinc
is, therefore, electro-positive to copper, and the lat-
ter becomes electro-negative. Electricity developed
at the zinc plate, is called positive; that at the cop-
per plate, ne^a<ii;e. Positive electricity passes /rom
the zinc through the dilute sulphuric acid, and is
Electrolysis. 225
collected at the negative plate ; so that if conduct-
ing wires be attached to the metals, the wire in
connection with the copper will conduct positive
electricity, and the one in connection with the zinc
will be the negative conductor.
The extremities of these wires, or rheophoies
{electrodes), are denominated poles ; or, positive pole
and negative pole, respectively. When the con-
ducting wires are in contact, or another conductor
is interposed between them, the circuit is closed;
otherwise the circuit is broken.
Other forms of battery, than the one described,
are common. The bichromate of potash battery
consists of the same materials, except it has carbon
instead of copper for the negative element, and a
solution of potassium dichr ornate mixed with the
dilute sulphuric acid. The action of the acid on
the zinc, as is well known, sets hydrogen free,
which accumulates on, or polarizes, the negative
plate, greatly interfering with the continuance of
the current. The solution of the potash salt, is
changed to chromic acid, which takes up the hydro-
gen, thus preventing the polarization referred to.
The liquid in such a battery consists of water,
1000 CC (fGm), = (2.11 pints), sulphuric acid,
350 CC = (11.85 f.^), potassium dichromate,
230 Gm. (7 §). Dissolve the latter in boiling
226 Inorganic Chemistry.
water, 675 CC (1.36 pints), and when cool, add to
the acid mixture.
The jpoles of the battery, when employed for the
purpose of mere analysis, are usually tipped with
platinum; and when these poles are immersed in a
compound liquid^ capable of conducting the current
from pole to pole, decomposition of that liquid will
ensue. The chemical affinity, i. e., the attraction
between the radicals of the molecules of which the
liquid in question is constituted, will be overcome
by the electric force, at the surface of the poles, the
intermediate portion of the liquid being apparently
unaffected. The following arrangement of the
molecules of water, when under the influence of,
the electric current, will serve as a sufficient exam-
ple, for the process of electrolysis in general :
Ihh} Ihh} Ihh} \Hh} IHh} iKH/HH-
The sign -|- in the above diagram, represents the
positive pole of the battery, and the sign — the
negative pole. It will be observed that free oxygen
appears at the positive pole, this element is there-
fore electro-negative to hydrogen ; and as hydro-
gen appears at the negative electrode, it is positive
to oxygen. In this way, the electric status of each
of the several elements is relatively determined.
Oxygen is the most electro-negative of the ele-
ments ; it must therefore be placed first, in the fol-
Electrolysis. 227
lowing comparative series. The other elements
are, severally, electro-negative to those which fol-
low them, and electro-positive to those that precede
them.
Electro-negative.
0
B
Sn
Ba
s
C
Pb
Li
:n"
Sb
Co
Ka
F
Si
iN-i
K
CI
H
Fe
Eb
Br
Au
Zn
'Cs
I
Pt
Mn
Electro-positive,
Se
Hg
Al
P
Ag
Mg
As
Cu
Ca
Cr
Bi
Sr
It will be further noticed that the non-metallic
elements, as a class, are electro-negative, while the
metals, comparatively, are decidedly electro-posi-
tive. The rarer elements are, for the most part,
ignored in the above classification.
The liquid state is essential to an electrolyte; the
thinest film of ice is sufilcient to arrest the elec-
tric decomposition of water. Mere solution, or
fusion by heat, will accomplish the object. But
all Hquids are not electrolytes; water itself, when
pure, is not a good conductor of the current, and
therefore suffers only slight decomposition, even
by a powerful battery ; whereas, if it contains a
228 Inorganic Chemistry.
very small proportion of sulphuric acid, it is ren
(lered a good conductor, and submits readily to the
process of electrolysis. Alcohol, ether, and numer
ous other compounds of organic chemistry, and a
few saline inorganic compounds, refuse to conduct,
and thereby avoid decomposition.
When oxygen salts in solution suffer electro-
lysis, they are at first divided into free metal and a
negative radical. Sulphuric acid (hydrogen sul-
phate, H2S04),is split up into free hydrogen, which
appears at the negative electrode, and sulphione,
SO4, which appears at the positive electrode. In
the same manner cupric sulphate, CUSO4, splits up
into metallic copper and sulphione, SO4 ; the SO4
loses an atom of oxygen, which escapes, and the res-
idue, SO3, unites with water to become H2SO4.
Sometimes the base of the salt is divided, so that free
metal appears on the cathode, and metallic oxide
on the anode. In case the metal is capable of de-
composing water, as potassium, for instance, it
will form a hydroxide, which will unite with the
acid present, to reproduce the typical salt.
2K0H + H,S04 r= K5SO4 2II2O.
The amount of decomposition of each electro-
lyte is perfectly definite, and is expressed for each
by the value of its chemical equivalent. The
equivalent value of water is 9 ; of hydrochloric
Electrolysis. 229
acid, 36.5 ; of potassium iodide, 166. Now, the
same current passing through these electrolytes,
will cause simultaneous decomposition of 9 parts
by weight of water, 36.5 of hydrochloric acid, and
166 of potassium iodide, and so on, for other elec-
trolytes as well, according to the same rule.
The process of electrolysis is subservient to
many useful applications in the arts, such as elec-
tro-plating with gold, silver, nickel, etc., and lately
with iridium. In the making of electrotype^ by
which the copper from cupric sulphate is deposited
in the impression of the type, set up in the usual
way, forming a coherent matrix for a permanent
duplicate cast. Fac similes of engraving plates,
medals, casts, etc., are obtained in this manner,
and the wonderful invention of photo-gravure de-
pends on this process of electrolysis.
For plating surfaces with silver .or gold, the cya-
nide of the metal, obtained by reaction between
silver chloride, AgCl, or gold trichloride, AuClg,
and solution of potassium cyanide, KC!N", is the
usual electrolyte.
A recent application of this process consists in
the deposition of silver, on plaster models of the
maxilla, for base-plates for artificial teeth. The
plaster is covered \yith graphite, which serves as a
conductor, outlining the size of the phite needed.
230 Inorganic Chemistry.
This is attached to the negative pole of the battery,
and metallic silver to the positive pole. The latter
is dissolved, more or less, by the influence of the
electric current, thus keeping up the strength of
the liquid, while the liquid itself, AgC^, in solu-
tion, is decomposed, the silver going to the nega-
tive pole until the required thickness of the plate
is obtained. Then, by an analogous process, the
silver plate receives suflacient deposition of gold to
render the finished base all that may be desired for
the purpose.
In all cases the article to be plated must be in
connection with the negative pole, inasmuch as the
electro-positive radical (metal), of the electrolyte,
is set free at the negative electrode. The positive
radical always appears at the negative pole, and
the negative radical at the positive pole.
Storage batteries are plates which become polar-
ized by receiving, on the prepared surfaces, elec-
tro-deposition of certain substances. These sub-
stances undergo further chemical change by
being placed in a liquid able to act chemically
on them, by which a secondary current is pro-
duced. For example, if a lead salt be decomposed
by electrolysis, metallic lead will be deposited on
the cathode (negative pole), and lead dioxide,
Pb02,onthe anode (positive pole). When plates
Electrolysis. 231
thus prepared are placed in dilute sulphuric acid aud
properly connected by outside conductors, a cur-
rent, reverse from the original, is developed by the
resulting chemical change ; the lead becomes oxi-
dized and the lead dioxide is reduced. In the ma-
jority of cases hydrogen and oxygen are the polar-
izing agencies, and thereby prove once more that
force, like the " coon, may be caught a coming or
a going:"
The Faradic current is an induced, interrupted
current, produced by wrapping around a hollow
cylinder of wood, thick, insulated copper wire, the
primary coil; the secondary coil, made of thinner
wire, is wrapped around the insulated first coil.
The hollow cylinder contains a bundle of soft iron
wire, which acts as a magnet, when a current of
electricity is passed through the inner coil. Near
the end of the soft iron wires there plays a bar,
also of soft iron, regulated by a spring, the latter
being in electric connection with the primary coil.
The current passing through the primary coil, in-
duces a secondary current in the outer coil, and in
the opposite direction ; the soft iron bundle is
magnetized by the current at the same time, and
attracts the soft bar of iron, whose removal thus,
breaks the current. In consequence of the break,
232 Inorganic Chemistry.
the bundle of iron is demagnetized, permitting
the iron bar to assume its former position,
which occasions a repetition of the phenomena,
so long as the current is supplied. The induced
current is necessarily a make and break, or, to and
fro current, the stronger shock being received
from the break.
Periodic Law, 233
CHAPTER XIX.
PERIODIC LAW.
The Periodic Law. — From the very earliest his-
toric times, the theories advanced in regard to the
ultimate nature of matter, possessed a peculiar
charm; The discovery of oxygeu by Priestly, in
1775, lent a fresh impetus to these studies.
Guyton de Morveau, in 1782, suggested the first
idea of systematic chemical nomenclature, followed
by Lavoisior, who elaborated the idea so fully, that
the present system of chemical nomenclature and
notation may be considered, with a few improve-
ments, to be Lavoisian. The atomic theory of
Dalton, later, accounted satisfactorily for the mathe-
matics of chemical reactions; and the relations be-
tween the constants of the elements and their
specific heats, and the electric behavior of the ele-
ments themselves, seem to confirm the truth of
Dalton's theory. Prout's hypothesis, in 1816,
that the atomic weights of the several elements
might be considered as exact multiples of the
atomic weight of hydrogen (a theory, by the way,
which is only slightly at variance with the present
20
234 Inorganic Chemistry.
accepted atomic weights, and which may be sus-
tained by further corrections), was followed by the
suggestion that possibly hydrogen was the " pri-
mordial matter that forms the other elements, by
successive condensations of itself."
In 1864 and 1870, Newlands and Mendelief, re-
spectively, independently of each other, erected
tables of the then known elements, beginning with
those of the lowest atomic weights, and advancing
regularly to the highest. They observed a natural
grouping of the elements that appeared to bear
some relation to their several atomic weights, and
to their quantivalence when determined by their
oxygen compounds; hydrogen alone, seeming to
be especially isolated from the rest. Therefore,
leaving hydrogen to itself, if we begin with the
element of next lowest atomic weight, viz., monad-
lithium, we find the progression to be as follows:
1. H, — -- _ — — _
2. Li7, Be9, Bll, C12, m4, 016, F19 —
3. Ka23, Mg24, A127, Si28, P31, S32, C135.5
If we study the position of the above elements, we
perceive that those to the left are metallic^ and those
to the right are non-metallic, while the interme-
diate elements, like silicon, possess chemical prop-
erties intermediate between the two extremes. We
notice that the line, commencing with Li, ends ab-
Periodic Law. 235
ruptly, with the acidulous fluorine, inasmuch as the
element of next atomic weight, Na, is decidedly
basic, and hence introduces another period. We
notice, further, that the corresponding members of
both periods have corresponding valencies, so that
if placed in vertical columns, all those in the same
column possess the same valency. The elements
in each group, in the following table, arrange them-
selves naturally in double columns, those on the
same side resembling each other in chemical prop-
erties. Each series is a small period ; series 1 and 2
the first large period ; series 3 and 4 the second, etc.
R represents one atom of any element, as RO
means one atom, united to one of oxygen, or RjO,
two atoms, etc.
236
Inorganic Chemistry.
H
M
o
H
O
-^
H
o
(—1
Q
O
1— 1
>
o
03
"2
1 O
00
IS
o
1-1
pi
o
T-i
cC
CO
Ol
1-1
u
1 1
1 1
1
1
>
5
a
r-l f-t
CO
1
1
>
ffio
P^05
O
CO
a
OO
V
CO
o
1^
1-1
1 ^
' 00
05
CO
P
>
in
1-1
r-(
CO
>
CO
<
S!5
r-(
1-1
w
00
1-(
83
H
00
§
>
WO
05 03
i-t
o
c^ o
i> o>
ON
00 O
»— 1 ^
i-t rl
q 0)
CBO
o
c^
Ph
CO
CO
c^
H
1— I
CO
lO
pq
<
GO
00
CO
tH
S3
B
CO
I-H
i
-■
o
03
1 '^
1 n
o
o
SB
u
CO
CO
w
»-<
be
w
1— J
JO
03
CO
to
OO
1—1
be
CO
eo
I— 1
09
00
CO
1-1 04
w*
io«o
t^OO
o> o
I— 1 1-1
Periodic Law. 237
The blank spaces in the foregoing table indicate
the probably proper places of elements as yet un-
known. Mendelief predicted the existence of two
elements — eka- aluminum and eka-horon — which
should fill the places now occupied by gallium and
scandium respectively, and described the general
physical and chemical properties of these elements
in advance of their discovery.
In consequence of the periodic law, the sugges-
tion is now accepted as truth, that "the properties
of an element are a periodic function of its atomic
weight." Those elements that unquestionably be-
long to the same group, often present remarkable
coincidences with reference to their atomic weights.
Thus, the atomic weight of sulphur is twice that
of ox^^gen, and if the atomic weights of sulphur,
32, and of tellurium, 125, be added together and
the product divided by 2, the result will be in the
immediate neighborhood of 78, the atomic weight
of selenium. Again, the atomic weight of phos-
phorus, 31, and of antimony, 120, added together,
give us the number 151, which is almost exactly
twice 75, the atomic weight of arsenic. The sum
of the atomic weights of chlorine, 35, and of iodine,
127, is 162, which, divided by 2, brings us suffi-
ciently near the atomic weight of bromine, 80, as
to appear something more than a mere coincidence.
238 Inorganic Chemistry.
CHAPTER XX.
SPECTRUM ANALYSIS.
In concluding the history of the individual ele-
ments, as well as many of their binary compounds,
it will not be inappropriate to allude briefly to the
subject of "spectrum analysis."
When sunlight is passed through a prism, it is
split up into what are arbitrarily called the " seven
primary colors of the solar spectrum." The colors,
however, of solar light, strictly speaking, are not
confined to merely seven in number, but are mani-
fested in infinite variety, each corresponding to a
special ''wave length." Sunlight furnishes a con-
tinuous band of light, broken by a great number
of fine dark lines ; but if the light from incandes-
cent individual terrestrial elements be dispersed by
passing through a prism, it will be found that only
a few colors are shown consisting of bright lines,
which are characteristic only of the elements pres-
ent in a state of luminosity, by which condition
their spectra are exhibited.
The instrument for examining the light given
ofi' by special substances, is called the " spectro-
Spectrum Analysis. 239
scope," and the process itself is called " spectrum
analysis."
When cempounds of sodium are heated in a
common flame sufficiently, the yellow light of so-
dium will confer on the flame a yellow color. In
the same way potassium compounds will cause the
flame to assume a decided violet tint. If there be
present in the flame both sodium and potassium
compounds, the intense yellow sodium light will so
overcome the purple potassium color that the pres-
ence of the latter element, although, perhaps, in
excess, will not be detected. If compounds of
either one of these elements be examined by the
spectroscope, the light of sodium will be indicated
by two bright, slightly different shades of yellow,
lines, so close together that ordinary instruments
show them as one bright yellow line. The light of
potassium will exhibit several bright lines, widely
separated, varying in color from strong violet to
red. Now, if compounds of both sodium and po-
tassium be examined simultaneously by the spec-
troscope, the peculiar yellow lines of sodium and
the purple and red and intermediate lines of potas-
sium will all appear distinctly, so that the presence
of both elements in the substance undergoing ex-
amination in this way can be ascertained with
certainty.
240 Inorganic Chemistry.
The metals thallium, caesium, rubidium, in-
dium, gallium, and others were discovered by this
process.
Barium gives lines of light of several different
colors, ranging from green to red ; strontium, bril-
liant shades of red and two of blue; thallium, only
one — a splendid blue line ; and calcium, quite a
number of lines, the yellow predominating. The
other metals also: gold, platinum, silver, iron, etc.,
may each be recognized by the peculiar bright
lines belonging to their spectra. N"itrogen exhib-
its a spectrum, mostly purple; and hydrogen one
bright red, one green, and one blue line.
Liquids and solids, when heated to incandes-
cence, exhibit continuous spectra. It is only lu-
minous vapors that give discontinuous, bright line
spectrums. To obtain this luminous vapor of
those elements which require a higher tempera-
ture for the purpose, than can be conferred by a
Bunsen flame, the electric spark is employed, which
in passing between two points of the metal in
question, volatilizes a portion, or in passing through
gases, as hydrogen, etc., heats them so intensely
as to enable them to give off the peculiar light
characteristic of each.
The spectrum of the sun, when examined by
means of the spectroscope, is found not to consist
V.
Spectrum Analysis. 241
of an absolute continuous band of light, ranging
from red to violet, but is seen to be interpersed
by hundreds of darJ{ lines, and these lines are
observed to correspond in exact position to the
bright lines in the spectra of terrestrial ele-
ments.
This coincidence in the position of the dark so-
lar lines with the well-known bris^ht terrestrial
lines, led to the assumption that the dark and
bright lines were produced by the same incandes-
cent elements. Later experiments proved such as-
sumption to be a fact. The brilliant lirne light
thrown on the field of the spectroscope shows a
continuous band of light similar to that of the
sun. If, however, the sodium flame be interposed
between the lime light and the spectroscope, the
continuous spectrum will show a double dark line
corresponding to the bright lines of sodium alone.
The conclusion is, tlierefore, reached " that the va-
por of an element has the power of absorbing
light-rays of the same wave length as those it
emits." In other words, the luminous sodium va-
por stops the light of the same wave length or
color, proceeding from the brilliant lime light be-
hind it. It is opaque to the colors of its own
kind, and allows the rest to proceed.
21
242 . Inorgayiic Chemistry.
The physical condition of the sun is at once in-
dicated by these experiments of KirchoiF. It con-
sists of a central incandescent liquid or solid body
which reverses the light of the luminous vapors
of the various elements in its own photosphere,
changing the otherwise bright lines into dark lines,
and these dark solar lines, corresponding in posi-
tion to familiar terrestrial bright lines, prove the
existence of the vapor of certain elements in the
atmosphere of the sun, with as great a degree
of certainty as any other question in physical
science.
Oxygen, hydrogen, iron, nickel, cobalt, manga-
nese, calcium, strontium, barium, chromium, mag-
nesium, sodium, copper, titanium, aluminum, lead,
cerium, cadmium, and uranium, have been identi-
fied as solar elements. The planets give the same
lines as those of the sun, as they shine by reflect-
ing his light.
Similar methods of observation prove the fixed
stars to be self-luminous suns. Many well known
elements have been recognized in the star Alde-
baran, and some also not as yet detected in the
sun, as bismuth, antimony, mercury, and tel-
lurium.
The true nebulce are ascertained to consist of
masses of glowing gas, inasmuch as they give
Spectrum Analysis. 243
bright lines, indicating only, with certainty, the
presence of hydrogen, a fact which seems to prove
the nebular hypothesis^ and also the evolution of
the various kinds of matter from one primordial
element.
PAR.T THIRD.
ORGANIC CHEMISTRY.
CHAPTER I.
INTRODUCTORY REMARKS.
There is but one science of chemistry. Its di-
vision into inorganic and organic, is simply one of
convenience.
It was formerly supposed that the production of
organic chemical compounds was restricted to the
influence of vital force in the bodies of plants and
animals. There is now, however, no boundary
line between the two divisions, inasmuch as many
organic compounds can be produced synthetically
from inorganic materials, and many others, such
as indigo, carbolic acid, etc., may be obtained by
artificial means. But nevertheless, the practical
source of organic compounds is from substances of
animal or vegetable origin, so that those who
erected organic chemistry into a separate science
really builded better than they knew, by present-
ing a division most convenient for the separate
(244)
Introductory Remarks. 245
consideration of the chemical nature of carbon and its
relations to the other elements.
Organized structures, that is to say, the various
tissues of animal and vegetable bodies, can not be
produced artificially. They are made up of chem-
ical combinations which obey, in unison with nat-
ural affinities, the governing power of vitality.
When vitality ceases, these tissues undergo resolu-
tion toward the formation of simple chemical com-
pounds, unless their identity is preserved by im-
mediate antiseptic treatment. When subjected to
a high temperature, with access of air (oxygen),
they are resolved at once, principally into H2O
and CO2 ; and if subjected to destructive distillation^
volatile and liquid substances are given off, leaving
a residue consisting of the charcoal variety of car-
bon ; and finally, if left exclusively to nature's
processes, decay supervenes by the agency of micro-
organisms; rapidly or slowly, according to the na-
ture of the substance, and its exposure to moisture
and certain temperatures.
Spontaneous disorganization of substances, rich
in nitrogen, is called putrefaction. They give off
compounds of an unpleasant odor, consisting
largely of ammonia and its derivatives ; whereas
those bodies of a non-nitrogenous composition,
losing their identity thus, are said to undergo fer-
246 Organic Chemistry.
mentation. In the latter case, the compounds re-
sulting are mainly devoid of unpleasant odors.
There is no essential difference in the nature of
the disorganization in those processes termed as
putrefection, fermentation, and eremacausis, except
in so far as the substances involved differ in chem-
ical composition ; but the part played by micro-or-
ganisms in the phenomena of changing complex
bodies into simplar forms, is as yet undetermined,
and would be out of place in a work of this kind,
even if we had fixed theories on the subject. It
will, therefore, be sufficient to remark in this con-
nection that micro-organisms are of various kinds,
and possess various functions. Some kinds of mi-
cro-organisms, the saprogenic, will affect changes
only in nitrogenous material, and even here, there
are many species of the useful pests, which divide
the process of putrefaction into several well marked
stages. This fact also obtains in fermentation.
Juices of various fruits, such as apples, etc., freely
exposed to the air and proper temperatures, un-
dergo changes finally resulting in alcohol (cider),
and this, if left to itself, by the agency of a special
*
micro-organic germ or ferment (the microdermi aceti),
will change into vinegar, otherwise known as
acetic acid. In the same way, special germs, acting
on different substances, induce individual distinc-
Introductory Remarks. 247
tions ill fermentation, such as lactic, butyric, etc.
In a given culture (decomposable substance), arti-
ficially prepared, as solutions of the carbo-hydrates,
lactic acid will result, by the influence of quite a
number of different bacteria, some of them known
as pathogenic (disease-producing), and others as
non-pathogenic.
The tendency of fermentation is to produce acids;
of putrefaction, to produce alkalies. In the latter
case, as already alluded to, ammonia and its deriva-
tives, the amines and amides are characteristic,
together with exceedingly poisonous and non-poi-
sonous diffusive ptoma-ines, or animal alkaloids,
resembling in their chemical nature, well-known
vegetable alkaloids, such as strychnine, atropine,
morphine, etc.
If the substance undergoing transformation by
bacterial influence, be composed of both fermentive
and putrefactive materials, then both acid and alka-
line products will occur. The fluid contents of the
a-verage human mouth, consisting of normal saliva,
mucus, and remains of various kinds of food, af-
ford an excellent example of a heterogeneous cul-
ture, and as more than twenty different kinds of
bacteria have been detected in the oral cavity, it is
easy to realize that in such a state of affairs, chemi-
cal riots will be the rule ; acid fermentation, tend-
248 Organic Chemistry.
ing to destroy the structural integrity of the teeth,
and alkali fermentation (putrefaction), tending to
induce an inflammatory condition of the softer tis-
sues of the mouth, oftentimes accompanied by
swellings and general septicaemia, the latter symp-
tom owing probably to the resorption of the poi-
sonous ptomaines.
As counteracting influences opposed to the above
conditions, we have the means of killing the mi-
crobes direct, by the employment of germecides, and
by disinfection, which destroys the infectious mat-
ter, and at the same time changes the physical, or
chemical, nature of the culture, so that it can not
serve any longer as suitable soil for microbic propa-
gation. Antisejptics applied to the part, and con-
tinued, after disinfection, will prevent a recurrence
of the fermentive process.
Germicides 'per se, are of little value as medicines,
so long as the culture remains intact, for, as we may
readily believe, the presence of living germs of the
common forms of both phases of fermentation is
practically universal. Disinfection, therefore, is the
Samson upon which the dental surgeon should rely,
followed by the exhibition of antiseptics, to prevent
a return of the disease.
The terms disinfectants and antiseptics, are often
improperly used indiscriminately; and although it
Introductory Remarks. 249
is impossible to draw a sharp line of demarcation
between these two classes of remedies, inasmuch
as some members of each (like silver nitrate, salicy-
lic acid, etc.), act more or less, in both capacities,
we will presume to draw a few distinctions between
them, which, on account of necessary brevity, will
no doubt appear rather too dogmatic.
It is a question yet in doubt as to whether full
grown micro-organisms, bacteria, exist in all infec-
tious matter; their absence therein does not, there-
fore, disprove the bacterial genesis of disease, or
of their necessary presence in inducing chemical
changes in the organized tissues that have lost
wholly, or in part, the governing power of vitality.
Their spores can yet live in the excrementitious
matter, and when planted in congenial soil, will
sprout and grow into the characteristic bacilli of
their kind. Poisonous ptomaines alone, when
forced into healthy living tissues play an impor-
tant part, not yet understood, in the production of
acute diseases. It follows accordingly, that any
means by which remaining bacteria, spores, and
ptomaines can be completely destroyed, must be
credited as belonging to the class of thorough dis-
infectants.
Disinfection can be accomplished in various ways.
First, by mechanical means ; removing the infec-
250 Organic Chemistry.
tious matter beyond the sphere of possible repro-
duction ("to the bottom of the sea").
Second, by extremes in temperature, especially a
high temperature, which kills bacteria, and spores,
and changes the chemical nature of the culture in
which they thrive, and also the poisonous products
of decomposition.
Third, by chemical means ; chemical action, as
we know, causes complete loss of identity in the
acting bodies, and where chemical changes take
place in infectious matter, it necessarily loses its
power of infection. Oxygen is involved in this
form of disinfection more than all other material
agencies combined. In the process oi fumigating,
by burning sulphur, the freshly formed sulphurous
oxide (SO2), deoxidizes the injurious organisms and
compounds, by taking away some of their structu-
ral oxygen, which change, of course, destroys their
identity. On the other hand, such incontestible
disinfectants as peroxide of hydrogen, potassium
permanganate, chlorinated lime, chlorinated soda,
etc., furnish active oxygen, which as stated under
their several heads, burns up the infectious mate-
rial, in the same way that nature's great disinfect-
ant, ozone, accomplishes its peculiar function.
The removal of all infected matter in caries of
the teeth, by instruments, is disinfection, Anti-
Introductory Remarks. 251
septic measures are then adopted, by proper meth-
ods of filling the cavity, to ^prevent a return of the
destructive phenomena in that part of the tooth.
Or complete removal of the contents in root canals
by instrumental manipulation, is thorough disin-
fection of the part, a labor requiring infinite care,
and which is generally supplemented by aid of
chemicals and a high temperature, followed by the
insertion of antiseptics, as the phenols, iodoform,
essentials oils, etc., in connection with the sealing
qualities of the filling.
A healthy part does not need disinfection, but it
does require antiseptic treatment, to prevent the
development of disease. The judicious use of the
tooth-brush, in a healthy mouth, is antiseptic treat-
ment by cleanliness, tending to keep the parts
therein in a healthy condition ; much alike in prin-
ciple and object to the treatment of fresh meats by
the use of the antiseptic, common salt. Wc might
multiply examples indefinitely to prove our thesis,
but the above brief remarks, we hope, will enable
the student to appreciate the distinction that really
exists between the two classes of remedies known
as disinfectants, and as antiseptics.
252 Organic Chemistry.
CHAPTER II.
CARBON COMPOUNDS.
The four points of attraction possessed by the
atom of carbon, furnish the basis by which organic
compounds are classified. These compounds are
made up, mainly, of carbon, hydrogen, and oxy-
gen, but many of them contain niti'ogen, phos-
phorus, and sulphur; also the haloid elements and
various metals.
Methane, CH4, serves as the best prototype of
organic compounds. As will be observed by its
formula, one atom of tetrad carbon — C — has its
I
valency of four, completely satisfied by union with
the four atoms of monad hydrogen ; so that the
saturated compound is not able to take up any
more monad atoms, except by displacement of an
equivalent number of the hydrogen atoms. In a
previous chapter, however, we alluded to the fact
that any dyad radical, elementary or compound,
can enter into direct combination with a saturated
compound, because the two units of combining
power, belonging to the dyad, so act as to neutral-
Carbon Compounds. 253
ize one unit of the compound it enters, and intro-
duce another, leaving the equivalency of the com-
pound the same as before.
Consequently, methane may take up the dyad
radical CHg" to form C2H6, as may be easily un-
derstood by the graphic formulas.
H H H H
i I II
H— C H(CHJ+— C— (CH2) = H— C— C— H {C^H.')
I I II'
H H H H
Methane Methene. Ethane.
On the other hand, methane, CH^, under cer-
tain circumstances, may lose two of its hydrogen
atoms, resulting in the development of the above
dyad radical methene; and ethane, C^Hg, may
lose two of its hydrogen atoms, and a new series
of hydrocarbon compounds be thus obtained.
The following table of some of the hydrocar-
bons, arranged and named by Hoffman, will enable
the student to appreciate the above statements :
254
Organic Chemistry.
CH
CH.
Methane.
Methene.
■
C,He
C,H,
(^2^2
Ethane.
Ethene.
Ethine.
^.
C^3^8
^sHg
C3H4
C3H,
^'
Propane.
Propene.
Propine
Propone.
s
C4H10
C4HS
C4H,
C4H4 C4H2
Quartane.
Quartene.
Quartine.
Quartone. Quartune.
C5H12
C5H10
^5^8
^5^6 ClgH^ C5H2
\
Quintane.
Quintene.
Quintine.
Quintone. Quintune.
3
^&^1A
^6^12
^6^10
CgH, C,H, CeH„etc.
^
Sextane,
Sextene.
Sextine.
Sextone. Sextune.
Greek prefixes are generally preferred; thus
pentane instead of quintane; hexane instead of sex-
tane; heptane instead of septane, etc.
Now, by reference to the table, it will be noticed
that the compounds in each vertical column differ
successively from each other, by CH2 ; and those
in each horizontal line, differ from each other suc-
cessively by H2. Those in each vertical column,
form each a homologous series, and those on horizon-
tal lines, an isologous series. The latter are also
called the monocarbon, dicarbon, tricarbon, groups,
etc.
The lowest member of each homologous series^
leaving out a few which are not known to exist, is
Carbon Compounds. 255
presented below as far as the eighteenth, together
with the general formula for each ;
Series. Lowest Member. General Formula.
1 CH4 CnH2U+2
2 C2H4 CnH2n
3 C2H2 CnH2n— 2
4 C5H6 CnH2n— 4
5 CgHg CnH2n— 6
6 CgHg CnH2n— 8
7 CgHg CnHgn— 10
8 CjoHg CnHsn— 12
9 C12H10 CnHan— 14
10 C14H12 CnHan— 16
11 Cj^Hjo CnH2n— 18
12 Cj^H,^ CnH2n— 20
13 CjeHjo CDH2n— 22
14 CjgHjg CnH2n— 24
15 C20H14 CDH2n— 26
16 CnH2n— 28
17 C22H14.... CnH2n— 30
18 C26H20 CnH2n-32
Cn means any number of carbon atoms, and
H2n + 2, twice as many hydrogen atoms and 2
over; CnH2n, twice as many hydrogen atoms as
as carbon atoms; CnH2n — 2, twice as many hy-
drogen atoms as carbon atoms, minus 2, etc.
The hydro-carbons in the first vertical column
256 Organic Chemistry.
on page 254 (series CnH2n-|-2), are all saturated
compounds ; those in the second column (series
CnHgn) are dyad radicals, capable of uniting with
2 atoms of chlorine without displacing hydrogen,
as in ethene chloride, C2H4CI2 ; those in the third
column, are triads, etc.
The first members, as methane, CH4 ; ethane,
C2Hg; propane, CgHg ; ethene, C2H4 ; ethine,
C2H2, etc., are gaseous at ordinary temperatures,
and increase in density in regular ratio, with each
additional CH2.
The higher members, of which C35H72 is the
extreme, are solid ; while the intermediate mem-
bers, such astetrane (quartane and butane), C^H^o ;
decane, O^qR^.^, etc., are liquid. The boiling
points of the liquid hydrocarbons increase regu-
larly, but in diminishing ratio with each increase
of CH2. Thus:
Tetrane, OJ^^^, boils at 0° (32F) Increase.
Pentane, C5H,2, " '' 38° (100) 38 C.
Hexaiie, C^R^^, " " 69° (156) 31
Heptane, C^Hig, " '' 98° (208) 29
Octane, CgHig, " '' 124° (255) 26
Carbon Compounds.
257
CHAPTER III.
CARBON COMPOUNDS.
The hydro-carbons, containing an even number
of hydrogen atoms, may exist free. Many of them
are known.
Hydro-carbon radicals, containing an uneven
number of hydrogen atoms, do not exist free, but
nevertheless maintain their integrity through oper-
ations of decomposition and recomposition, just
like the elements themselves, ranking as units, like
the atoms of hydrogen, oxygen, gold, etc. They
are derived from the hydro-carbons of even equiv-
alency, in the same way that hydroxyl (HO), is
derived from H2O. A few of the most common
occurrence are subjoined:
CH
Methane.
Ethane.
C3H,
Propane.
Butane.
CH3
Methyl.
CJI5
Ethyl.
C3II,
Propyl.
cjr,
Jiutyl, etc.
CH2''
Methene,
C2H4"
Ethene.
CsIIe"
Propene,
CH'^'
Melhenyl.
C2H3'''
Ethenyl.
Fropenyl.
The final syllabic yl indicates a compound radi-
22
258 Organic Chemistry.
cal of uneven valency; so also certain rajilicals of
both uneven and even valency, not derived from
saturated hydrocarbons, as nitryl, NO^, carbonyl,
CO, etc. The derivation of certain other radicals
suggest their names ; thus from ammonia, ^Hg, by
abstraction of one atom of hydrogen, is derived
amidogen, NHg ; and by taking away two atoms of
hydrogen from Nllg, is derived the dyad radical,
imidogen, I^H''. Cyanogen (meaning blue), C^
(quasi symbol Cy), when free, is formulated as
C!N"-C^, analogous to the molecule of chlorine,
Cl-Cl, and when acted upon by a metal, as Kg, re-
sults according to the equation,
K^ + Cy, = 2KCy
Potassium. Cynogen. Pot. Cyanide.
Just like a molecule of chlorine on a molecule of
potassium, Kg + Clg, = 2KC1. The radical cya-
nogen, CN, (Cy) is one-half the molecule of free
cyanogen, just as the atom of chlorine, CI, is the
radical of the free molecule of chlorine, Cl-Cl.
These latter compound radicals, carbonyl, nitryl,
amidogen, imidogen, and cyanogen, are not strictly
classified as organic, but are interesting in this
connection, inasmuch as they enter largely into
the formation of many accepted organic com-
pounds.
The hydrocarbon radicals, however, such as
Carbon Compounds. 259
nictliyl, nietlienyl, ethyl, propyl, etc., are the ones
that should engage our especial attention in study-
ing organic chemistry. They behave, as before
remarked, similarly to the atoms of the elements,
and like the latter, are relatively electro-positive
or electro-negative. With 0, CI, etc., they are
electro-positive, as in ethyl oxide, (0115)20, and
ethyl chloride, CH5CI ; and electro-negative, in
metallic salts, as in lead ethide, rb(CH5)2.
From them, all well defined organic compounds
maybe presumed to be formed, most of which may
be assumed to be derived from the following
members :
1- Alcohols. — Formed by the union of hydro-
radicals with hydroxyl.
CHg,OH C2H5,OH C2H4(OH), C3H5(OH)3
Methyl Alcohol. Ethyl Alcohol. Ethene Alcohol. Propenyl Alcohol.
Alcohols are really hydroxides^ analogous to the
hydroxides of metals. Thus sodium hydroxide,
NaOH, calcium hydroxide, Ca(0II)2: The first is
similar in composition to methyl and ethel alco-
hols, and the latter to ethene alcohol.
2. Oxygen Ethers. — Are formed after the water
type, 11 — 0 — U, and consist of hydrocarbon radi-
cals and oxygen. Common ether is ethyl oxide,
0211,5^0 — 02115. A mixed ether contains more
than one hydrocarbon radical ; methyl-ethyl
ether, OH 3 — O — Ogllg, is a mixed ether.
260 Organic Chemistry.
3. Haloid Ethers, are compounds containing
hydrocarbon radicals, and a haloid element; chlo-
roform, CIICI3 is a haloid ether, made up of the
trivalent hydrocarbon radical methenyl, and three
atoms of univalent chlorine.
Iodoform CHI3, and "Dutch Liquid" C2H4CI2,
are also examples of haloid ethers.
4. Organic Acids, may be defined as -oxygenated
hydrocarbon radicals and hydroxyl, as acetic acid
C2H3O, OH, formic acid CHO, OH, lactic acid,
C3H5O2, OH. The molecule of an organic acid,
therefore contains at least two .atoms of oxygen ;
they may also be regarded as being produced by
union of a hydrocarbon residue and the univalent
I
radical carhoxyl COOH, graphically 0=0 — 0 — H,
thus acetic acid CH3COOH ; formic acid, H, COOH ;
lactic acid C2H5O, COOH. Where but one group
of carboxyl is shown, as in the above, such acid is
monobasic^ giving up only the hydrogen of carboxyl
to a metal ; and when two such groups are shown,
CH,— COOH,
as in succinic acid, | it is dibasic.
CH2— COOH,
5. Esters, are ethereal salts, formed by hydro-
carbon radicals, and organic or inorganic acid
radicals, for example ethyl acetate, C2H5, C2H3O2.
Ethyl alcohol and nitric acid, yield the ester, ethyl
nitrate, and water.
C2H50H+HN03=C2H5N03+H,0.
Carbon Compounds. 261
6. Aldehydes, meaning less hydrogen than is
contained in the corresponding alcohols, are com-
pounds, intermediate between alcohols and acids.
That is, they contain less hydrogen than the alcohol,
and less oxygen than the corresponding acid, and
are derived by the removal of hydrogen from the
alcoliol, by oxygen, all of which may be understood
by the empirical formulas :
C^HgO + 0 = C2H4O + H2O.
Ethyl Alcohol. Aldehyde.
C2H4O + O = C2H4O2.
Aldehyde. Acetic Acid.
An aldehyde can be converted into an alcohol,
but an acid can not.
7. Ketones are derived from aldehydes, by replac-
ing one atom of hydrogen by an alcohol radical.
Acetone.
or they may be considered graphically as two
univalent radicals, held by bivalent carbonyl CO.
The ketones are quite numerous, of which acetone
is the best prototype. Acetone itself, may be re-
garded as dimethyl ketone CH3
0=0
CH3. There are also
diethyl, and ethyl-methyl, etc., ketones.
8. Amines, are derivatives of ammonia by sub-
stitution of hydrogen, by hydrocarbon radicals.
262 Organic Chemistry.
,H fC.fi, fC^Hj fC^H,
Ammonia. Ethylamine. Diethylamine. Triethylamme.
The amines are numerous, and are mostly basic
in character. Where all the hydrogen is removed,
the trivalent radical IT is evidently capable of taking
up three univalent radicals as above, or one triva-
lent radical, as below :
Methenyl Nitril. Ethenyl Nitril.
These trivalent nitrils are not basic ; they are all
neutral, except the first, which is acid, capable like
HCl, of exchanging its hydrogen for a metal, and
may therefore be regarded as composed of hydro-
gen and the univalent radical cyanogen,
I^CH -= HCK
Methenyl Nitril. Hydrogen Cyanide.
(Hydrocyanic Acid).
ITC2H3 = CH3CK
Ethenyl Nitril. Methyl Cyanide.
Analogous to the amines, are the arsines, stibines,
and fhosjMnes.
9. Amides are analogous to the amines in com-
position, except they contain acid radicals, instead
of hydrocarbon radicals. Those which are made
up of a bivalent acid radical, and imidogen, are
called imides.
C2H30,KH2 C4H4O2NH
Acetamide. Succiuimide.
Carbon Compounds. 26B
CHArTER IV.
CARBON COMPOUNDS.
When two or more corapoiinds can be represented
by the same empirical formuhx, they are said to be
isomeric. The difference in the chemical and physi-
cal nature of isomeric bodies, is due to the difference
ill the relative position, or arrangement, of the
atoms in the molecule, and it is upon this fact that
the somewhat startling innovation o^ stereo-chemistry
is founded.
True isomeric bodies are those which have the
same kind and number of atoms, not grouped into
special compound radicals. These isomers react
similarly, by the influence of the same reagents.
There are many examples of this class, two of
which will suffice :
H
H I
I H-C-HH
• H-C-H I I
H-(^-n H— C C-II
H-O-H I I
H-C-H H-C-HH
H-C-H H— 6— H
i
H
Pentane. Isopentane.
264 Organic Chemistry,
Metameric isomers, are those bodies which have
the same composition, but differ greatly in their
transformations under similar circumstances ; as an
example, the formula C3Hg02 represents methyl
acetate, ethyl formate, and propionic acid, two of
which we subjoin graphically.
H3C
H3O H^
i
0-rC— 0— CH3 0=C— O— H
Methyl Acetate. Propionic Acid.
Polymeric compounds are those which have the
same percentage composition but difier in molecu-
lar weight. Examples of this class are found in
the series, homologous with CH2:
Ethene (ethylene) C2H4.
Propene (propylene) C3Hg.
Tetrene (bytylene) C^llg.
Pentene (amylene) C^IIiq.
Several essential oils are isomeric with oil of
turpentine, C^ qHj g ; and others are polymeric with
the latter, having the formulas, C20H32 C3QH48,
etc. All polymeric compounds, exhibit regular
gradation in density, and boiling points, from the
lowest to the highest.
Optical isomerism, possessed by similar com-
pounds, is due, according to stereo-chemistry, to
asymetric carbon atoms in each molecule.
Carbon Compounds. 265
The above examples of isomerism show the im-
portance of rational formulas. The empirical
formula of methyl alcohol, for instance, is CH4O.
The rational formula is CH3OH. The formula
C2H4N2O, expresses the number and kind of atoms
in both ammoniuyyi cyanate and carbamide^ and
might also be supposed to suggest the direct union
of methane and nitrous oxide; but if each be for-
mulated rationally, we can then have easy con-
ception of differences in their chemical and phys-
ical properties.
Ammonium Cyanate. Carbamide (Urea).
Ammonium cyanate can be prepared from inor-
ganic sources. Its molecular transformation into
urea by Wohler marked the lirst artificial produc-
tion of an organic compound.
23
266 Organic Chemistry,
CHAPTER V.
PARAFINS, SERIES CnH2ii+2.
The formulas of the first members of the me-
thane series of hydrocarbons, suggest asymmetrical
arrangement of the atoms of hydrogen, in con-
nection with the atom of carbon. The four points
of attraction belonging to the latter, are properly
represented by the four solid angles of a tetrahe-
dron, to each of which is attached an atom of hy-
drogen in methane. In the next member, ethane,
containing two atoms of carbon, one point of at-
traction belonging to each, is united to the other,
leaving 3 points free to unite with hydrogen, and
so on with the next member, propane, where the
middle carbon atom can satisfy only 2 of hydro-
gen. Such stereo arrangement can not be repre-
sented on a plane surface, except feebly in per-
spective, but the following diagrams will ade-
quately express the mathematical values of each
compound :
Parajins, etc.
267
H
H
H
H C H
H
Methane.
H C H
H-
-0-
-C-
-C-
n
-H
H C H
H
Ethane.
H-
H-
-H
-H
Propane.
Modifications of these molecules are probably
impossible, and therefore there are no isomers of
methane, ethane or propane, but with the next
member, butane, C4H1Q, it is possible to write the
graphic formula in at least tw^o w^ays ; and it is a
fact that two kinds of butane are recognized :
H
H H-C— H
I I
11— C C— H
H ii_i_H
Isobutnne.
As the individual hydrocarbons, of this or other
series, increase in the number of carbon atoms, it
is evident that many modifications are possible,
and a corresponding number of isomers may be
produced. A mathematical limit, however, in each
case, is also evident.
268 Organic Chemistry.
The methane series of hydrocarbons are found in
petroleum. The first four members, are gases, the
fifth a light liquid, and so on, increasing in specific
gravity by each increase in CH2 ; the latter mem-
bers, being solid. Parafin itself is a mixture of
the higher members.
Methane, CH^, as well as each of the other satu-
rated hydrocarbons is formulated rationally as a
hydride, to indicate the presence of a compound
radical which retains its identity in many reactions.
For example, methyl hydride, CH3, H (methane),
when acted on by chlorine forms methyl chloride
CH3, CI. Ethyl hydride C2H5,H (ethane) simi-
larly also forms, by losing an atom of hydrogen,
ethyl chloride C2H5CI, etc.
By acting on methyl chloride, with excess of
chlorine, the isologous radical methenyl, CH, is
produced; this takes up, 3 atoms of chlorine, and
methenyl chloride, chloroform, CHCI3, results.
Chloroform however, is commercially prepared, by
distilling together, either methyl, or ethyl alcohol,
and bleaching powder.
2C2H60+5CaCl202=2CaC03-f2CaCl2+Ca(HO)2+4H20+
Alcohol.
2CHCI3.
Chloroform.
Chloroform is a haloid ether, of an agreeable
odor. -It is a colorless liquid, of specific gravity
1.52, and boils at 62° (143 F.). Its molecular
Parafins, etc. 269
weight as seen by formula, is, in round numbers,
120; its vapor density compared with hydrogen, is
one-half its molecular weight, or 60, and as air is
nearly 15 times as heavy as hydrogen, the vapor of
chloroform is therefore about 4 times as heavy
as air.
The purest chloroform is now made from chloral
lu'drate. It possesses strong solvent powers on the
diiFerent oils, camphor, caoutchouc, resins, the
amines, and bromine and iodine. It is not inflam-
mable; is freely soluble in ether, and alcohol, and
sparingly so in water.
Materia Medica. — Chloroform has been a favorite
anaesthetic from the period of its introduction in
1847, but on account of the many fatal cases which
have occurred under its influence, it is being dis-
carded more and more, in favor of ether. Its em-
ployment alone, or in combination with other
ansesthetics, in the simple though painful opera-
tion of extracting teeth, is not regarded as legiti-
mate practice by the highest authorities in our
profession. It kills by direct heart paralysis, prob-
ably due to the physical change which chloroform
produces in the blood itself. The strong tendency
to immediate coagulation of fresh blood, by outside
experiments with chloroform, is at least suggestive.
270 Organic Chemistry.
Locally applied, chloroform is an irritant, and
reduces painful impressions in the part ; it is also
a good haemostatic. Taken internally it is em-
ployed as an anti-spasmodic and anodyne.
Dose, 0.06-0.30 fGm. {y(i i-v).
For iuhalation 4. — 8 f Gm. (f^i-ij).
Iodoform, methenyl iodide, CHI3, is a haloid
ether, analogous to chloroform, and, like the latter,
is a derivative of methane. It is prepared by
heating to a temperature of 40° (104F), an alco-
holic solution of potassium iodide with bleaching
powder. It occurs in small yellow crystals, some-
what volatile, giving oii'an unpleasant saffron-like
odor ; is insoluble in water, but is freely soluble in
oils, chloroform, ether and alcohol.
Materia. Medica. — Iodoform is a typical anti-
septic; applied to a disinfected part, it effectively
prevents the development of both alkali and acid
ferments. As a dressing to ulcerous sores, open
and sloughing wounds, it is anaesthetic, and stimu-
lates healthy granulations by preventing profuse
discharge and consequent irritating sequelse.
As an antiseptic dressing in root canals of teeth,
it is favored by many of our most eminent prac-
titioners, notwithstanding its rather enervating
odor. This single objection to iodoform is easily
overcome by the addition of either one of several
ParaJinSj etc. 271
essential oils, which act both as adjuvans and cor-
regens to its medicinal value.
The principle of the Blair apparatus, by which
iodoform is vaporized by heat and forced into root
canals, is a correct idea in therapeutics; ^. e., the
thorough disinfection by the heat required to hold
the vapor, and the immediate deposition of the
sublimed iodoform, which fills the open spaces,
and by its insolubility and iodic action on micro-
organisms, prevents a return of the disease. A
thermometer attached to the apparatus would be
desirable — together with other improvements — as
the compound easily decomposes by heat into free
iodine and hydrocarbons, principally ethene, C^H2,
2CHI3 + q. s. Heat = 1q + C,H2.
Iodoform is neither a local nor general irritant.
Internally exhibited, it is antiseptic, anodyne,
stimulant, alterative, and tonic. It is not loholly
decomposed in the body, as its odor can be de-
tected in the blood and the several tissues.
Dose, 0.06—0.012 Gm. (gr. i-ij)
Bromoform, methenyl bromide^ CIIBrg, is another
haloid ether, analogous to the foregoing com-
pounds, but is not important. To show these bodies,
as derivatives of methane, the simplest possible
organic chemical hat-rack is erected :
272 Organic Chemistry.
H CI I Br
H-C— H H— C— CI H-C-I H— C-Br
i
H CI I Br
Methane. Chloroform. Iodoform. Bromoform.
Alcohols, etc. 273
CHAPTER VI.
ALCOHOLS, ETC.
Methyl Alcohol, CH3OH, is known as wood
spirit, obtained by the dry distillation of wood, and
may also be produced by direct synthesis; it is a
constituent of oil of winter-green from gaultheria
procumbens. It is a colorless mobile liquid, of spe-
cific gravity 81, which boils at 66° (150F), and is
used as a substitute for ethyl alcohol in various
manufacturing processes.
The alcohols are not necessarily similar in phys-
ical properties to common alcohol. Some of them
are solid, but all may be regarded as consisting of
hydrocarbon radicals and hydroxyl.
They are called monatomic, when the molecule
contains only one group of hydroxyl (OH) ; and
they are known as primary^ secondary and tertiary,
according as the carbon atom in combination with
hydroxyl is also united to one, two or three other
carbon atoms.
H rcH,
c<
H pjH
on
Methyl Alcohol. EthyfAlcohol. Propyl Alcohol
H ^^H
on i^on
274 Organic Chemistry.
If the hydrocarbon type of the alcohol be pre-
served, there can be no modification of the first
formulas; in other words, there can be no isomeric
alcohols of these; but the higher members of the
series, as butyl (tetryl, or quartyl), alcohol CJl^^O,
etc., admit of three modifications, and form three
insomeric alcohols, primary, secondary and ter-
tiary.
f
rCH,CH,CH3
CH,CH3 rcH3
CH„ r. I CH,
CH3
c 1 c^— » c<;_
tOH I^OH I^OH
Primary. Secondary. Tertiary.
Primary alcohols of the methane series are con-
verted into aldehydes by losing 2 atoms of hydro-
gen, and then by oxidation into corresponding
acids.
Secondary alcohols in losing by oxygen, 2 atoms
of hydrogen, are converted into ketones; as second-
ary propyl alcohol.
rcH3
(, I CH3 - H, = CH3 - CO - CH3
' H Minus. Dimethyl Ketone.
[oh
And
fCH2CH,
(.ICH3-1I, = CH3-C0-C,H,
) H Minus. Methyl-ethyl Ketone.
Secondary Butyl Alcohol.-
Alcohols^ etc. 275
Ketones are CO, united to two univalent hydro-
carbon radicals.
Tertiary alcohols do not yield either aldehydes,
ketones, or acids, containing the same number of
carbon atoms as do the alcohols themselves, but are
split up into bodies which show a less number of
carbon atoms. Thus, with tertiary butyl alcohol :
cJ ?S3 + o, = cn,o, + C,H,0, + H,0
OH
CHo Formic Acid. Propionic Acid.
The following table contains in empirical form-
ulae, the known monatomic alcohols and corres-
ponding acids, together with acids which have no
known alcohol prototypes :
Z/l)
Organic Chemistry.
o
+
o
<1 'p^
t- Pw^lnw '^n 00 I -co CO (M • Oi lO CO t^ CC 00
^ j^eiow zu. ,— I 'M Tif lo o • CO t^ 1^ t- 1^ 00
O
OOOOOI^CiCiOO
Or— i-^COt^OlOiCOCO
"^^ "^O o ooooooooo
o CO CO Oi Ol O Tf
;:^ t^ Oi O CO lO CO
. d
• n^ O • • • • • Oi lO
• Ph oi t^ 00
! +j ! . ! . .
• 1; .....
^-OOOO
,_ O W O IM ■* «5
s^ to 00 ,-1 -H rH ^
l-H hM HH -J-l ^ HH HH
>-Ih m CO -<i< m CO t~-
OOQOOOO
O
I^" .
^
^
t^ .
CO
ffi •
ffi
o
:o
_l
,_(
Q .
GO
CO PJ
in CO
1:- O
c;i
a;
a;
Ethyl Alcohol^ etc. 277
CHAPTER VII.
ETHYL ALCOHOL, ETC.
Ethyl Alcohol, C2H5OH, is the active prin-
ciple of brandy, rum, whisky, beer, ale, and wine.
It may be produced by synthetic processes,
and by various reactions, but is practically ob-
tained by fermentation of starchy and saccharine
substances, such as the different grains, cane sugar,
fruits, etc.
The mashed grain in aqueous solution, fer-
ments by aid of the yeast germ, the starch being
turned into glucose; a weak solution of alcohol is
thus obtained.
Glucose. Alcohol,
This alcoholic solution is then distilled^ and the
process repeated until about a 90 per cent alcohol
is obtained. The water still remaining, is par-
tially removed by distilling with quicklime; the
product is then called absolute alcohol, a colorless
liquid of sp. gr. 80, of a pungent burning taste and
spirituous odor. Is boils at 78.5C and freezes at
— 130.5C. Alcohol mixes with water in all propor-
tions; is a solvent for various gums and resins, in
278 Organic Chemistry.
the making of medicinal tinctures, and is used in
many chemical and manufacturing processes; it
is also a valuable antiseptic against putrefaction
and burns in the air, evolving great heat.
Proof spirit contains about 50 per cent of alco-
hol : whisky, rum and brandy, from 40 to 50 per
cent ; wines from 5 to 20 per cent, and beer, from
3 to 7 per cent.
Alcoholic or vinous fermentation will run into
acetous fermentation, unless prevented by joas-
teurizing, by heat or by bottling, or the use of
chemicals.
C2H6O + O =: C2H4O + H2O
Alcohol. Aldehyde.
C2H4O + 0 = C2H4O2
Aldehyde. Acetic Acid.
AcET- Aldehyde C2H4O. This compound is the
best known of its class, called aldehydes. They
contain the group COH, and are intermediate be-
tween the foregoing alcohols and their correspond-
ing acids.
Acet-aldehyde, also formulated as acetyl hy-
dride, C2H3O.H, is produced by oxidation of di-
lute alcohol, and by several other processes. It is
a clear liquid of sp. gr. 0.81, at 1°; of an ethereal
suffocating odor, and mixes in all proportions with
water, alcohol, and ether. With chlorine it forms
acetyl chloride, CH3O.CI; with nascent hydrogen,
Ethyl Alcohol, etc. 279
alcohol; and with oxygen, acetic acid. It reduces
metallic silver from a solution of the nitrate, and
unites with the alkali metals, and with ammonia,
to form solid compounds, C2H3O.NH4. Polymers
of aldehyde are known, a doubling and trebling of
the molecule, as C4Hg02, and C^H^<^0^, It is
isomeric with ethene oxide and acts in many cases
as the oxide of a dyad, under the name of alde-
hydene.
Acetic acid, C2II3O2.H (in the dilute state,
known as vinegar), is the most familiar of the acids
corresponding to the methane series of alcohols.
The first of this series of acids is formic acid,
CHO2H ; next, acetic, and so on. With each ad-
dition of CH2 they vary in their physical proper-
ties, ranging from the light volatile formic acid, on
to, and above, the 9-carbon molecule, where they
become semi-solid, of waxy or greasy consist-
ency; hence their general nsuney fatty acids. The
best known of these higher acids, are palmitic, mar-
garic, stearic and mellissic.
Acetic acid is generally obtained by fermenta-
tion (oxidation) of wine, cider, etc., or from the
alcoholic mash from which spirit is distilled.
When pure, it is a colorless liquid which, at a tem-
perature of 18 (64.5F), freezes into a solid ; hence
the name, glacial acetic acid. It mixes in all pro-
280 Organic Chemistry.
portions with water, alcohol, and ether, and is mon-
obasic, forming, with metallic bases, salts called
acetates^ and with alcohol radicals, such as methyl,
ethyl, etc., it forms esters or compound ethers ; in
these cases, giving up one atom of typical hydro-
gen to make room for the base, just like similar
reactions with the inorganic acids. Acetates of
iron and aluminum are used as mordants in calico
printing. Verdigris is copper acetate ; and sugar of
lead is plumbum acetate, Pb (0311302)2 + ^ Aq.
The latter compound is of great value to the
• chemist, and possesses soothing astringent medic-
inal properties. Oalcium carbonate will dissolve in
acetic acid (even dilute) forming calcium acetate
Ca(C,H302)2.
Compound ethers, formed by the fatty acids
with the alcohol radicals of the methane series,
are becoming quite important as flavoring extracts.
The peculiar flavors of fruits are probably due to
the presence of these same esters in the substance
of the fruits. Amyl acetate, 05H^^02H302, has
the flavor of bananas; ethyl butyrate, O2H5C4
H7O2, of pineapples, and amyl valerate, OgH^j
O5H9O2, is known as '' apple oil." We may here
state, as a matter of some interest, that when or-
ganic esters are treated with caustic alkalies the
acid radical unites with the alkali metal, and the
Ethyl Alcohol, etc. 281
typical alcohol of the hydrocorbon radical is
formed. For example :
C.HuC^HjO^ + NaOH = NaC2H30, +
Amyl Acetate. Sodium Acetate.
C5H11OH
Amyl Alcohol.
Acetic acid acted upon in different proportions,
by chlorine, yields three well-defined chloracetic
acids, by giving up hydrogen. It is not, however,
the hydrogen of the group COOH in the acid,
which is replaced by chlorine, as is the case when
acted upon by metals.
Acetic acid, CgH^Og
Monochloracetic acid, C2H3CIO2
])ichloracetic acid, C2H2CI2O2
Trichloracetic acid, C2HCI3O2
The aldehyde of trichloracetic acid is the liquid
chloral, C2HCI3O, a substance which, united with
water, forms the familiar chloral hydrate.
Chloral is prepared by prolonged action of chlor-
ine gas on pure ethyl alcohol.
CgllgO + 8C1 = 5HC1 + C2HCI3O
It is a thin, colorless, oily liquid, of little taste,
but pungent odor; its sp. gr. is 1.502, it boils at 94^
(201F), and is freely soluble in water, alcohol,
and ether. Solutions of caustic alkalies decompose
it into formate and chloroform.
C2lI(M30 + KOII = KCIIO2 -H CIICI3
Chloral. Pot. Formate. Chloroform.
24
282 Organic Chemistry.
Chloral forms with water in molecular propor-
tions, chloral hydrate^ C2HCl30,H20, a solid crys-
talline soluble substance of peculiar odor and sharp,
unpleasant taste. It melts at 46° (114F), and boils
at 97° (206F).
Materia Medica.— Locally applied, chloral hy-
drate possesses sedative, anaesthetic and antiseptic
properties, and is assuredly an excellent topical
remedy as an ingredient of liniments for the relief
of neuralgia and rheumatic pains. Powdered
chloral (hydrate) pressed into the alveolar pockets,
in pyorrhose, will serve the double capacity of
anodyne and antiseptic. Applied in substance to
slightly moistened sensitive dentine, it cuts off,
partially, indirect communication with the pulp by
extracting moisture from the tubuli ; and to the
exposed pulp, either alone or combined with cam-
phor, or with aconite tincture, it causes, probably
by the same physical change, an immediate lessen-
ing of pain. It is of service also in the cure of in-
dolent ulcers in the mouth and other parts.
Taken internally, chloral acts as a sedative to the
entire nervous system, and secondarily to the heart.
As a hypnotic, it reduces the blood pressure on the
brain, and thus induces sleep by imitating the nat-
ural anatomical phenomenon of that process, and
by diminishing at the same time the conductivity
Ethyl Alcohol, etc. 283
of the sensory nerves. Awakening is not accom-
panied by the digestive disturbances, nausea, and
headache, which usually result from the use of
opium.
In full doses chloral slows the heart's action and
respiration, and lowers the temperature. It may
cause death by either syncope, or coma, and those
addicted to the chloral hahit often suffer with scor-
butic sores and ulceration of the gums.
Dose: 0.30 - 1.25 Gm (gr. v - xx).
R. Chloral hydratis.
Pot. Bromide, aa 0.65 Gm (gr. x).
Syrupi aurantii cort.
Aq. menth pip. aa 15.00 f Gm (f.^ss).
M. S, A hypnotic potion in acute alveolar abscess.
284 Organic Chemistry.
CHAPTER YIII.
ETHERS, ETC.
Oxygen Ethers are defined as alcohols (typical),
with the hydroxyllic hydrogen replaced by an al-
cohol radical. Thus :
Ethyl Alcohol. Ethyl Oxide.
They may nlso be regarded as bearing the same
relation to the alcohols that metallic oxides bear to
the metallic hydrates, and all belong to the water
type.
ll\^ 1^2\^ Na|()
Hp H p Nap
Sodium Hydrate. Sodium Oxide.
Ethyl Alcohol. Ethyl Oxide.
Ethyl Oxide (0.^115)20, comynon ether ^ known
also as sulphuric ether, can be obtained from a
large number oH ethyl compounds, as for instance :
c,Hj + c.nJo = Ki + %fAo
Ethyl Iodide. Pot. Ethylate. Ethyl Ether.
Ethers, etc. 285
Practically, ether is obtained from ethyl alcohol
by the dihydrating influence of sulphuric acid, at
the proper temperature :
2C,H,0 - 11,0 = C.Tli^O for, {C^ll,).0,]
Alcohol. Ether. I J
Ether is a clear mobile liquid of a strong, though
not unpleasant odor, and a warm penetrating taste.
Its specific gravity is 0.730. It is not readily solu-
ble in water, and is not as good a general solvent as
chloroform. Its boiling point is dangerously low,
35-5° (96F), and at still lower temperatures it
evaporates rapidly ; the vapor is about two and a
half times as heavy as air, and is highly inflam-
mable. If ether be freely exposed to the air, it
tends to oxidize into acetic acid.
Materia Medica. — Inasmuch as the rapid ab-
straction of heat from a part reduces sensibility,
the local employment of ether in the form of spray,
on account of its volatility, has been favored to
some extent in the operation of extracting teeth.
Ether internally administered in the form of
Iloft'mann's anodyne, which is a compound of ether,
alcohol, and ethereal oil, is antispasmodic, stimulant,
and carminative ; in the preparation known as
spirits of nitrous ether, composed of alcohol and
ethyl-nitrite (02115^02), it is an excellent diuretic
and diaphoretic, in fevers.
286 Organic Chemistry.
The first practical use of ether as a general
anjBsthetic was made by Dr. Morton, a dentist of
Boston, in 1846.
Althoug?i much slower in its immediate eifects,
ether is considered a safer anaesthetic than chloro-
form ; the stimulus to the heart is more pronounced,
and continuous than with chloroform, albeit, ether
should not be exhibited no more than other anaes-
thetics wherever decided weakness of the heart,
lungs, or brain, is seriously suspected.
In ether narcosis, the cerebrum seems to be the
first of the nerve centers involved ; then the sensory,
followed by the motor centers, of the cord ; and
finally the sensory and motor functions of the me-
dulla oblongata; thus, in the later stages inducing a
slowing of both the heart's action and respiration.
The time required for complete etherization, is from
three to five minutes, and the quantity of ether,
about 60.00 Gm (gij).
We may here place on record merely as a fact,
and not in any degree as encouraging to dental
quackery, the composition of so-called vitalized air.
To one gallon of nitrous oxide gas, is added three
drops of an equal mixture of alcohol and chloro-
form.
Ethyl chloride, C2H5CI, on account of its ten-
dency to induce excessive cold by rapid evaporation,
Ethers, dc. 287
lias been employed as a local aiuestlietic for sensitive
dentine, etc.
Chlorine forms with the different series of
homologous hydrocarbons, a new homologous
series in each case; each member differing from the
next, by CH2, and containing equivalent chlorine
as a substitute for liydrogen.
CTI3CI CII2CI2
Methyl Chloride. Mithcne Chloride.
Ethyl Chloride. Etheuo Chloride.
C3H7CI C3HgCl2
Propyl Chloride. Propeae Chloride.
The density of these haloid ethers, increase in
regular gradation, by each addition of CH2, just like
the tj^pical saturated hydrocarbons. Indeed, we
can almost realize in every instance, the physical
properties of organic compounds, by observing
their molecular weights, as to whether they are
gaseous, liquid, or solid, and in every instance the
vapor density of the substance, compared with
hydrogen, is ascertained by dividing its molecular
weight by 2.
Thus methyl chloride, CII3CI, is a gas 25 times as
heavy as hydrogen, a little more than one and a half
times as heavy as air. Ethyl chloride, C^lTsCl, is
a light liquid, the vapor of which is two and a half
times as heavy as air; and ethyl bromide, CgllsBr,
is a liquid almost twice as heavy as water, although
288 Organic Chemistry.
it boils at a lower temperature, 72 (163F.) Its
vapor density is nearly four times that of the at-
mosphere.
Mixed oxygen ethers contain two different alcohol
radicals, united to hydroxylic oxygen. They are
produced by various reactions, as for example :
^^4 o + C,H J = KI + CH, I 0
-^ J Ethyl Iodide. P FT J
Pot. Ethylate. ^2'^^5
Methyl-ethy] Ether.
Methyl-ethyl ether,^^ | O Boils at 11°C
Ethyl-butyl " ^2^5 Iq u 3Q0
Methyl-amyl " ^^| |o " 92°
Ethyl-amyl " ^2^5 |q u 112°
The other alcohols of the methane series, aside
from those already alluded to (methyl and ethyl
alcohols), and amyl alcohol, are interesting to us
only as chemical curiosities.
Butyl and propyl alcohols, and those following,
are susceptible of isomeric modifications. Cetyl
alcohol^ CjgHggOII, is characteristic of spermaceta ;
and rnelyl alcohol, CgoHg^^OH, is a necessary con-
stituent of beeswax. These alcohols are solid.
Spermaceta and beeswax are really compound
ethers, or esters, formed by alcohol radicals, united
respectively to palmitic and melissic acids.
Mhers, etc. 289
Amyl alcohol, pentyl alcohol, Cgll^^OH, is the
chief constituent of fusel oil, and occurs as a
residue, after distillation of ethyl alcohol, espe-
cially from the starch of potatoes. When pure,
amyl alcohol is a colorless liquid, of unpleasant
burning odor and acrid taste. Its specific gravity
at 0° is 0.825. It boils at 130 (266F), and freezes
at — 20°. It changes by oxidation into valeric acid.
CHI
Amyl acetate, p^tt^A > 0, as its name suggests,
is an amyl ester which, on account of its pear-like
odor, is used in flavoring cheap confectionery.
Amyl nitrite, C5Hi^]S"02, is also a compound
ether, obtained by action of nitric acid on amyl
alcohol; is a yellow colored oily liquid, of sp.
gr. 0.877, volatile, and inflammable; boils at 83
(182F), and emits a persistent diffusive odor of
ripe pears. In materia medica this ether is known
as amyl nitris, and is used as a stimulant to the
heart, in case of ordinary syncope or exces-
sive anaesthetic narcosis. The vapor from 2 or 3
drops, inhaled from a napkin, produces immediate
flushing in the face, dilatation of the arterial
system and rapid pulsation and breathing. If
pushed too far, the symptoms of carbon dioxide
coma supervene. Its employment with ansemiac
patients is safer than with those of plethoric habit.
25
^90 Organic Chemistry.
CHAPTER IX.
OLEFINES, ETC.
The homologous hydrocarbon series CnHgn, next
isologous to the paratins, are simple multiples of
CH2. They are dyad radicals, produced by ab-
straction of two atoms of hydrogen from the satu-
rated paraiius. Thus —
CH4 — H2 rzr CH2
Methane. Methene, or Methylene.
C2H6 — H2 = C2 H4
Ethane. Ethene, or Ethylene.
« - H, = CgHe
Propene, or Propylene.
« - H, = C.Hg
Tetrene, or Butylene.
Penrene, or Amylene, etc.
These dyad hydrocarbon radicals are known as
olefines, from the fact that the most important mem-
ber of the series, ethene C2H4, forms with, chlorine,
an oily liquid, CgH^Clg-
The first free members of the series, ethylene and
propylene, are gases; butylene is an exceedingly
volatile liquid, which boils at 3° (37F),and amylene
also, which boils at 35° (95F) ; the higher members
of the series, as melene, CgoHgQ, are solid.
OlejineSy etc. 291
The olefines maybe formed by various reactions,
only one of which we will mention, i. e., the ab-
straction of water, from corresponding monatoraic
alcohols (methane series), by powerful dehydrating
agents, such as sulphuric acid, zinc chloride, or phos-
phoric oxide. Thus —
Amyl Alcohol. Araylene.
The alcohols of the olefine series are diatomic, as
ethylene alcohol, C2H4 (0H)2. They are called
glycols because the}' are intermediate in the series
belonging to ordinary alcohol, and the series of tri-
atomic alcohols, of which latter glycerine, C3H5
(OH) 3, is the best known.
Diatomic alcohols, glycols, produce by oxidation,
two series of acids, monobasic an-d disbasic, re-
spectively. The first is derived by replacing 2
atoms of hydrogen, in ethylene, for instance, by 1
atom of oxygen, and the second by replacement of
all 4 atoms of hydrogen by 2 atoms of oxygen.
CII2OH C2OH COOH
CII^OH COOH COOU
Ethylene Alcohol Glycollic Acid. Oxalic Acid.
The acids of the glycollic series having but one
group of COOH are monobasic ; those of the oxalic
series are dibasic. Accordingly we have the gly-
collic, or lactic acid series:
29^ ' Organic Chemistry.
Carbonic acid, CHoOg
Glycollic acid, C2H4O3
Lactic acid, CgHgOg
Butylactic acid, C4Hg03
Valerolactic acid, Ogll^QO^
And the oxalic series:
Oxalic acid, C2H2O4
Malonic acid, C3H4O4
Succinic acid, 04Hg04
Pyrotartaric acid, CgHgO^, etc.
Lactic acid is the characteristic acid of sour milk.
It is formed also by lactic fermentation of glucose,
and starch, and many other vegetable products by
the influence of several bacteria, the special microbe
penicillium glaucum being probably the most charac-
teristic. The acid is now extensively prepared by
supplying a pure culture of lactic ferment to glu-
cose obtained from corn starch. It can also be
obtained artificially, by direct oxidation of propy-
leue glycol, C3H, (OH)^ + O^ = H,0 + CgHeO,,
and by various other chemical processes. It is
found in the stomach and small intestines ; the flesh
of animals also contain an isomeric modification,
called para-lactic acid. All the salts of lactic acid
are soluble in water and alcohol, insoluble in ether.
Lactic acid is a heavy liquid of specific gravity
1.215 ; it is highly hygroscopic and is soluble in water,
alcohol, and ether. The formula :
Olefines, etc. 293
f OH \ j
\COOH/^^^)
CH2— OH
-^ COOH / (^ 6H2-COOH,
will enable us to understand the reactions that may
occur between lactic acid, and positive radicals.
With metals such as zinc, and calcium, it is only
the hydrogen of the group COOH that gives its
place to the metal; the metals of the alkalies
however are capable of removing likewise, the
hydroxylic hydrogen. In this connection the fol-
lowing formulas are suggestive :
2(CH3-CH <coo)^^- ^^3-CH<^(^(^j^^
Calcium Lactate. Sodium Lactate.
Disodium Lactate.
Hydrocarbon radicals can displace either the alco-
holic hydrogen, or the basic hydrogen, or both, in
the lactic series of acids, and these acids therefore,
can form three different ethers. As,
Ethyl Lactic Acid Monoethyl Lactate.
CH3-CH<g5%H»j^^
Diethyl Lactiite.
The principal exciting cause of caries of the teeth,
has been generally accepted, since the published
experiments of Prof. W. D. Miller, as due to lactic
fermentation in the mouth. Food carbohydrates,
amylaceous, and saccharine, are especially disposed
to this form of fermentation,
294 Organic Chemistry,
starch. Glucose, Levulose, and Dextrose
CeHi,Oe=2C3He03.
Glucose. Lactic Acin.
Ci2H.,Oi,+H,0-4C3He03.
Grape or Milk Sugar. Lactic Acid.
Free lactic acid destroys the bacteria that produce
the fermentation ; but the acid as it developes in
the cavity of decay, is at once neutralized at the
expense of the mineral portion of the tooth struc-
ture, calcium lactate, CaCCsH^Og),, being formed,
which permits a continuation of the process.
Oxalic Acid, C2H2O4, is the characteristic acid
of wood sorrel and rhubarb. When evaporated from
solution, it occurs in prismatic crystals, resembling
magnesium sulphate, but very poisonous. It may
be produced artificially, by oxidizing starch or
sugar, with nitric acid, and is now largely manu-
factured from sawdust.
Oxalic is the first of a long homologous series of
acids ; the immediate succeeding members are given
on page 292. They are all dibasic, and can there-
fore form both normal and hydrogen salts. Of
these, succinic acid is the most interesting on ac-
count of its relation to malic and tartaric acids.
CII -COOH CHOH-COOIl CHOH-COOIl
I 1
iH,-COOH CH2-COOH CHOH-COOIl
succinic Aoid. Malic Acid. Tartaric Acid.
Olefines, etc. 295
Malic is the acid of apples, and certain other
fruits and vegetables, it occurs in white soluble
crystals.
Tartaric acid exists in the juice of grapes, tama-
rind, etc. During the fermentation of wine, potas-
sium tartrate is deposited on the sides of the wine
casks ; hence the name tartar, is given to deposits
on the teeth.
Tartaric acid occurs as a white crystalline sub-
stance, of very sour taste. It forms the contents
of one of the papers, in Seidlitz powder; the other
paper containing a mixture of hydrosodium car-
bonate and potassium sodium tartrate. On solution
in water, effervescence, by the escape of CO 2, takes
place.
Cream of tartar, is hydrogen-potassium tartrate,
TT 1
-j^ >C4H40g; the best varieties of baking-powders,
are mixtures of cream of tartar, and hydrogen
sodium carbonate (bicarbonate of soda).
The moisture of the dough, when heated induces
the following reaction :
HNaC03+HKC4H406=KNaC4H40e4-H20+C02.
Rochelle Salt.
The escaping CO2, raises the dough, thus confer-
ring lightness; the Rochelle salt remains with the
bread.
296 Organic Chemistry.
Tartar emetic is tartrate of potassium and anti-
mony, qi ^ VC^H^Og, used more or less in medi-
cine, as an emetic.
Citric acid, CgHgO^, although not related to the
above, is also a fruit acid, being found in the juice
of oranges and lemons; and in other fruits, as
gooseberry, currant, etc., in company with malic
acid.
This acid is tribasic, as may be seen by the sub-
joined condensed formulae :
Hj Hj
Citric Acid. Monopotassium.
Citrate.
Hj Kj
Dipotassiura. Tripotassium.
Citrate. Citrate.
Fatty AcidSy etc. 297
CHAPTER X.
FATTY ACIDS, ETC.
By reference to the table of corresponding alco-
hols and acids on page 276, it will be seen that the
solid acids, named pahiiitic, margaric and stearic
belong to the group of monobasic /a^^y acids. Pal-
mitic acid, Cigll3202, occurs as an ether of pro-
penyl, in many natural fats, and in palm oil; also
in cetin of spermaceti, and in melissin of beeswax.
It is a solid, lighter than water ; it melts at 62°
(144F), and when heated with alcohols, yields
compound ethers. Margaric acid, C^rjU^^O^^is in-
termediate between palmitic and stearic acids. The
latter acid, CigHggO, occurs in the more solid fats
of animals ; also in the softer fats, as butter and
goose grease, and in some of the fats of vegetable
origin, as in cocoa butter. Stearic acid is a solid,
a little heavier than water; it melts at 69° (162F)
and distils without alteration.
Oleic acid, C18II34O2, is monabasic, but belongs
to another series of acids, having the general
formula, CnH2n — 2^2- -^^ ^^ ^^^ fluid constituent
of most natural fats and fixed oils; it solidifies at
298 Organic Chemistry.
4° (39F), and is, therefore, liquid at common
temperatures ; its specific gravity is 0.898. These
fatty acids are found in nature as ethers of the
radical propenyl, C^H^'^'.
Glycerine, Glycerol, is propenyl alcohol, and as
propenyl, is a triad radical, the alcohol in question
must be triatomic.
fOH
{ OH
(OH
With some monobasic acids, therefore, this alco-
hol may form three distinct ethers, as with acetic
acid :
CC,R,0, (C2H3O2 fC^HgO^
C3HJ0H C3hJc,H30, C3HJCHO
(-0H (OH (C,H30,
The natural oils and fats are generally found as
triple (normal) ethers of palmitic, margaric, stearic
and oleic acids :
CgH^'^'^OH
C3hJc,,h,,o, C3hJo,,h O
IC16H31O, lCi,H330
Palmitin. Margarine.
c3hJc,,h::o: c3hJc;h o
t-CisHjsO^ IC13H35O
Stearin. Olein.
When these fatty ethers are saponified by alka-
lies, a salt of the alkali metal (soap) is formed, and
propenyl alcohol thus set free.
Fatty Acids, etc. 299
C3H5 (Ci3H3502)3 + 3K0H = 3KCi«H3,02 + C3H, (0H)3
Propenyl Stearate. Pot. Stearate. Prepenyl Alcohol.
(Stearin). (Soap). (Glycerine).
Glycerine is also produced in small quantity in
sugar fermentation, and is now separated largely
from the fats, hy high pressure steam.
When acted on by dilute nitric acid, glycerine
exchanges 2 atoms of hydrogen for 0, forming
glyceric acid.
CH2OH
CHOH
I
COOH
When treated with strong nitric and sulphuric
acids, glycerine yields the explosive compound
known as nitro- glycerine, C3H5 (^Ogjg. This pro-
penyl-nitrate is a thick oily liquid ; it burns quietly,
but if struck fiercely or ignited by a fulminate, it
explodes witli frightful violence. It is the basis of
different varieties of dynamite, which consists of
absorbed nitro-glycerine in infusorial earth or saw-
dust, etc., to a porous pasty solid, of less danger in
handling than the liquid.
Glycerine itself is a syrupy liquitl of sp. gr. 127,
is nearly colorless, and of sweetish taste. When
pure, it is said to boil at the high temperature of
290° (554F), a fact which suggested its employment
in an open dish for valcanizing rubber, to avoid the
danger attending the ordinary method.
800 Organic Chemistry.
•
Commercial glycerine contains too much water
to permit a sufficient elevation of temperature for
the purpose, and even where the pure variety is
used, acrid vapors consisting of acrolein^ C3H4O,
are given oft*, the same as from the wick of an im-
perfectly quenched candle.
Materia Medica. — Glycerine is soluble in water
and alcohol ; insoluble in chloroform and ether.
It is a good solvent for various drugs, such as tan-
nin, creosote, carbolic acid, iodine, borax, quinine,
etc. It is antiseptic and soothing, and is applied
as an emollient to sore or inflamed surfaces, either
alone or as a vehicle adjunct for other remedies, as
in the following Glycerita:
Glycerina, . 30.00 fGm. (fgi)
Acidi Tannici, 8.00 Gm. (^ij)
Glycerina, . 30.00 fGm. (fgi)
Acidi Carbolici, 8.00 fGm. (f^ij)
Glycerina, . 30.00 fGm. (f^i)
Sodii Biboras, . 8.00 Gm. (gij)
The univalent radical allyl, CI3H5, is isomeric
with the trivalent radical of glycerine, propenyl.
They differ in structure, however, as the following
formulas will show :
Fatty
Acids,
etc.
H
1
H L
H-C-
-OH
-OH
H C H
C H
H C OH
H
Allyl Alcohol.
H C
H
Glycerol.
-OH
301
The natural oil of garlic owes its pungency to
allyl sulphide (C3H5)2S ; the oil of mustard, to allyl
sulphocyanate, C3H5CNS.
302 Organic Chemistry.
CHAPTER XL
AMYLENE, ETC.
We have alluded to the olefines, dyad hydrocar-
bons of the general formula, CnH2n, and stated
that one source of their derivation is by dehydrat-
ing the alcohol of the same number of carbon
atoms. Thus, isopentene (amylene), CgHj^, is ob-
tained by action of dehydrating agents, such as
sulphuric acid, zinc chloride, phosphoric oxide,
etc., on pentyl (amyl) alcohol,
C,HiiOH-H,0 = C,Hi„.
The formula, CgHj^, is capable of four modifi-
cations. Normal pentene, sometimes regarded as
ethyl-allyl, C2H5,C3H5, is obtained by action of
sodium on mixed ethyl and allyl iodides. The
third possible modification is not well known,
while the fourth variation, is probably identical
with the new anaesthetic called pental.
These possible variations of C^H^q are repre-
sented below :
Amylene, etc. 303
1st. CH3 — CH, — CH2 — CH = CH2
Normal Pentene.
2d. QH^>CH — CIL= CH2
Isopentene.
3d. CH3 — CH2 — CH = CH — CH3.
4th. qh'>C == CH — CH3
Pental.
Pental is said to be produced from amylene hy-
drate (amjlene alcohol), by heating in the presence
of acids. This hydrate is isomeric with amyl alco-
hol. They differ, however, in certain properties,
and therefore must differ in structure.
C^HjiOH C5H1JOH
Amyl Alcohol. Amylene Hydrate,
If these two alcohols be acted on by the same
dehydrating agent, the resulting compounds would
differ in some of their properties. They must,
however, have the same vapor density. The boil-
ing points of normal pentene, isopentene (amylene),
and pental, approximate 35°-38° (95-104F), and
probably vary in this respect, only on account of
difference in absolute purity. Their specific grav-
ities also approximate 0.663-0.6783. They are in-
soluble in water, but mix freely in ether, chloro-
form, and alcohol. They are exceedingly volatile
and inflammable, and their vapor, when inhaled,
causes insensibility to pain.
304 Organic Chemistry.
Amylene was introduced as an ansesthetic in 1856,
but made slight impression. Pental was intro-
duced to the profession in this country in 1891.
Its odor somewhat resembles that of mustard oil,
suggesting the radical allyl.
The claims made for pental as an anaesthetic in.
dental operations, are :
To reach narcosis, requires but from 1-3 minutes.
Heart's action and respiration are not materially
interfered with.
There is no spasm of the muscles.
The narcosis is brief, and the patient recovers
without any accompanying headache, nausea or
vomitings l^evertheless, pental has not been re-
ceived thus far with as much favor as its friends
think it deserves.
The series of hydrocarbons, CnH2n — 2, of which
Ethine (acetylene), C2H2, is the only important
member, belong to the fatty compounds, like the
paraffins and alefines, as distinguished from the
aromatic compounds. The first two numbers are
gases, the others increasing in density through
liquid and solid states, by each additional CH2.
Acetylene, C2H2, is a constituent of coal gas, on
which it confers, largely, a disagreeable odor. It
may be produced by various decompositions of
organic compounds, but it is especially distin-
Amyhne, etc, 305
giiished ag the only compound, formed synthetically
by direct union of carbon and hydrogen.
When a strong electric arc current is passed
from carbon poles through an atmosphere of hy-
drogen, the carbon, as it volatilizes, unites with
the hydrogen, 2H + 2C = C2H2.
From acetylene, a great number of organic com-
pounds can be obtained. Thus, by aid of platinum
black, it will take up 2 atoms of hydrogen to form
ethylene, C^H^, C^H^ -f H2 = CJi^.
Ethylene combines with concentrated sulphuric
acid to form basic ethyl-sulphate, 03114 + H2SO4
= H, C2H5SO4, and this, when heated with caustic
potash, yields as follows : ^
H, C2H5SO4 + 2K0H = C2H6O + H2O + K2SO4
Alcohol,
In ethane, C2Hg, the 2 carbon atoms are united by
1 bond, in ethene (ethylene (C2H4), the carbon atoms
are united by 2 bonds, and in ethine (acetylene) the
carbon atoms are united by 3 bonds, thus :
H
H— C— H
H— C— H H— C-H C— H
I II III
H H— C— li C— H
Ethane. Ethene. Ethine.
The hydrocarbons of the general formula, Cn
26
306 Organic Chemistry.
HgH — 6, are represented by the first member of the
series, Benzene, C5gHg, (not the petroleum product,
Benzine); the second member Toluene, C^Hg, is
also frequently miscalled benzol and toluol. The
other members of the group, are susceptible of
isomeric modifications, and they all belong to the
Aromatic series of hydrocarbons, so named because
many derivatives of benzene, such as benzoic acid,
oil of bitter almonds, etc., possesses a fragrant
odor.
Benzene, C^Mq is chiefly obtained from the coal
tar of the gas-works. It is a light highly inflam-
mable liquid, which boils at 80° (176F.) and freezes
at 3° (37F.) ; it is soluble in alcohol and ether,
scarcely so in water, has an ethereal odor, and is
produced largely, for the manufacture of aniline
dyes.
The six carbon atoms in benzene, form a closed
ring ; they are united by 1 and 2 bonds, alternately,
permitting one bond, belonging to each atom to
remain free, forming thus a quasi hat-rack, which is
capable of receiving alternately, innumerable ele-
mentary or compound univalent radicals ; so the
derivatives of benzene may be considered practically
illimitable, and thousands of them are already
known.
Benzene, etc.
30
c c
H C C H
// \
H C C H
\ /
H C C CH
\ /
H C-=C H
Benzene Ring.
(Hat-rack).
Benzene.
Methyl Benzene.
(Toluene).
Groups of compound radicals like CHg attached
to the nucleus ring, in the place of II, form lateral
chains, which themselves may give up H, to form
substitution derivatives.
The homologues of benzene, as toluene, etc.,
(CgIIg + CH2, etc.), may be derived by substitution
of methyl, CHg, for one or more of the six hydro-
gen atoms ; and where but one hydrogen atom is
removed from benzene, the compound radical j)/ien?/^,
C5II5, is presented.
Benzene itself, is the hexune of Hoffmann ; and its
homologues are isologous with many hydrocarbons
of great interest, and practical use, such as cinna-
mene, Cgllg, naphthalene, C^QlIg, and anthracene,
Cj4H^Q, and the terpenes, Cj^Hig.
PAen?/?rt^co/io^,CgH5 0H, commonly called carbolic
acid, is usually obtained from coal tar by distilla-
tion, between the temperatures of 150° and 200°
(302-392F.) It is also produced by various other
methods of reaction on benzene derivatives, and
by dry distillation of organized complex substances,
such as coal and wood.
308 Organic Chemistry.
This phenol shows its relation to benzene, by the
graphic formula : H — C — C — H
H_C C— 0— II
\ /
H— C=C— H. Although not
an acid, it takes its name as such, because it forms
salts with the alkalies, such as potassium phenate
OgHgOK, by giving up its hydroxylic hydrogen to
the metal. This reaction however suggests an
alcohol, and moreover, carbolic acid forms, like
the alcohols, compound ethers, such as methyl
phenate O^H^ — 0 — CHg, {anisol), and ethyl phe-
nate CeH^r^O— C2H5, (phenetol), etc.
Materia Medica. — Phenyl alcohol, carbolic acid,
phenic acid, simply phenol, w^hen pure, occurs in
clear prismatic needles of specific gravity 1.066;
it melts at 40° (104F), and boils at 181° (357F). It
possesses a smoky odor and burning taste. It
forms a complete aqueous solution with 95 per
cent of water, and will liquefy by the presence of
5 per cent of water.
It acts as a local anaesthetic when applied to soft
parts, as the dental pulp, probably by forming,
with albuminoids, a protecting coagulum. It acts
as a superficial caustic when applied undiluted,
and is one of the best antiseptics, so long as the
coagulum, which it forms with the substance of the
Benzene, etc. 309
tissue acted on, or with the substance of bacteria
themselves, remains undissolved.
When dissolved in chloroform, ether, or alcohol,
the caustic properties of carbolic acid are enhanced;
it also dissolves in the essential oils and in glycerine,
which somewhat diminish its causticity. It is an
active poison.
Dose, 0.06 Gra. (grj) in solution, or pill.
Antidotes, olive oil and saccharated lime.
Bobinson's Remedy, composed of equal parts of
carbolic acid and caustic potash, is useful in al-
veolar pyorrhoea, and with arsenic, for destroying
dental pulps.
Phenol Sodique is a solution in water of 5 parts
carbolic acid and 1 part of caustic soda, useful as
an ingredient of antiseptic mouth washes. Phe-
nol trichloride is antiseptic and a powerful disin-
fectant.
B. Acida carbolici, 2.00 Gin. (3ss)
Glycerin!, . 10.00 fGm. (fsijss)
Aq. Rosaq. s. ad., 120.00 fGm. (f^iv)
M. 8. Antiseptic solution.
Creasote is a product of the distillation of
wood tar, and is a mixture of several phenols,
such as carbolic acid, creasol, C8H1QO2, and cre-
sylol, C^IIgO. These latter may also be attached
to the benzene hat-rack:
810 Organic Chemistry.
H-d C— OH H— C 6— OH
H— C-=C— OH H— C=C— H
Creasol. Cresylol.
Creasote is an oily liquid of specific gravity 1.08.
It possesses a caustic burning taste, and a pene-
trating empyreumatic odor. On long exposure to
light, it turns to a reddish yellow. It mixes in all
proportions with ether, alcohol, acetic acid, and
naphtha, but not with glycerine. With water it
forms two solutions, 1 part creasote to 80 of water,
and 10 parts creasote to 1 of water. It may be
distinguished from carbolic acid by producing a
green instead of a brown color, with alcoholic so-
lution of ferric chloride.
Creasote possesses many of the virtues of car-
bolic acid. It is antiseptic, anaesthetic, escharotic,
and styptic. When applied to exposed dental
pulp, it effectually relieves the pain; and when di-
luted, it is useful as an application to ulcerative
conditions of the skin and mucous membrane. It
is preferred to carbolic acid as an internal remedy
in phthisis, nausea, cholera, and passive hem-
orrhage.
Dose, 0.06-012 fGm. (ntj-ij)
Antidotes, same as carbolic acid.
Benzene Group. 311
CHAPTER XII.
BENZENE GROUP.
The aromatic alcohols of the henzene homologues,
are formed by substitution of OH for H in the lat-
eral chains, and contain the group CH^OH. As,
H_C— C— H H— C— C— H
H_C C— CH, H— C C— CH.OH
\ / ' \ /
H— C=.C— H H— Cr=C— H
Toluene. Benzyl Alcohol.
They are therefore primary alcohols. They change
to aldehydes, and acids, by oxidation, and yield
ethers, analogous to those of the monatomic
alcohols.
Benzoic Acid, CgllgCOOlI, is characteristic of
the urine of herbivorous animals. It exists already
formed in certain balsams and gum resins, as in
gum-benzoin f which exudes from the Styrax Benzoin
tree of Borneo, and adjacent countries. It may
also be obtained by various reactions on many
benzene derivatives. It is an inodorous solid, but
when warm, emits a faint agreeable odor; it melts
at 120° (248F.) and boils at 250° (482F.) ; is freely
soluble in alcohol but sparingly so in water. Its
812 Organic Chemistry.
salts called henzoates are generally soluble in water
and have the formula, MC^HgOg.
Calcium benzoate is changed by dry distillation
into calcium carbonate and benzone, or the ketone
of benzoic acid.
Ca(C,H50,), =CaC03 + C.H^-CO-OgHj.
Benzoic acid is a good germicide and antiseptic,
and is stimulant to mucous surfaces. It is proba-
bly the most active ingredient of the antiseptic
mixture known as Listerine, and is also one of the
ingredients of ^'Harris' Gum WasA." It is used
internally in gout, calculi, inflammation of the
bladder, and incontinence of urine.
Dose, 0.50 Gm. (gr. vij.)
Benzoin tinctures, are effective in treatment of
ulcerative inflammation of the oral mucous mem-
brane, and of sloughing wounds.
Ammonium benzoate, ^}l^CrjlIfi2^^^ antacid and
stimulant, and is acceptable to the stomach, in acid
dyspepsia.
The new substance, saccharine, which is said to
possess 300 times the sweetening power of cane
sugar, is a derivative of benzoic acid. It is the
anhydride of orthosulphamidobenzoic acid.
Benzaldehyde, is the familiar fragrant oil of bitter
almonds.
Salicylic acid, QqW^^^^^^^jx occurs in salicin, of
Benzene Group. 313
the willow and poplar, and free, in the flowers of
meadow-sweet; and as niythylic ether, in oil of
wintergreen (Gaulheiia procinnhens)^ from which
it may be obtained by distillation with potash. It
is however principally prepared by heating sodium
phenate with carbon dioxide.
Salicylic acid appears as a white crystalline
powder, freely soluble in glycerine, alcohol, and
ether, sparingly soluble in water; is without odor,
or taste, but leaves a sweet astringent aftertaste;
it is resolved, by heating with pounded glass, into
carbon dioxide, and phenol. It is an excellent anti-
septic, and is somewhat disinfectant, and is fre-
quently employed with good results, in powder or
ethereal solution, as a dressing in suppurating root
canal ; and in alcoholic solution with borax, in
treatment of aphthae, and other inflammatory con-
ditions of the mouth. Mild alkalies, as borax and
Hodii phosphas, increase its solubility. It is afi:ec-
tive as a deodorizing dentifrice, when combined in
proper proportion with suitable vehicles; when in
strong solution, its acid nature is objectionable to
the teeth.
Dose, 0.50-1.25 Gm. (gr. viij-xx.)
Gallic Acid, dioxysalicylic acid, trioxybenzoic
acid, CyHgOg, may be also erected on the benzene
ring.
27
Si 4 Organic Chemistry.
H-C— C— OH
H— C C— OH
\ /
HO— C=C— COOH
Gallic acid is a constituent of nut galls, and
many other vegetable bodies, but is most conven-
iently prepared from tannin. It is acid in reaction^
is only slightly soluble in cold water, but freely solu-
ble in hot water, and in alcohol, ether, and glycerine.
It possesses astringent and styptic properties.
Dose, 0.10-0.30 Gm. (gr.ij-v.)
Tannin, tannic acid, gallotannic acid,
C,,R,,0, == 0 C,11,={0R),
CO-CeH^^COH)^
COOH
Ordinary tannic acid is obtained from nut galls,
which are produced as an excrescence on the young
twigs of the species of oak known as the quercus
infectoria, by the puncture of the insect cynips gallce
iinctorice. The galls are irregularly rounded and
tuberculated nuts, from J to } of an inch in diame-
ter, of a green gray color, and of decidedly astrin-
gent taste. The favorite galls, come chiefly from
the Levant. They are rich in tannic, and gallic
acids.
Medicinal tannin, is obtained from powdered galls
by the action of commercial ether. It is a feathery
Benzene Group, 315
amorphous powder, of a light yellow color, soluble
iu water, glycerine, alcohol, and ether. It produces
coagula with gelatine and albumen, smd precipitates
with vegetable alkaloids, and with ferric com-
pounds. These substances are therefore incompat-
ible with tannin.
Materia Medica. Locally applied tannic acid
is especially astringent. It is therefore suggested
as a good local application in inflammations of the
mucous membrane, in either one of the extreme
portions of the prima via. In passive hemorrhage,
sometimes excessive, after the extraction of teeth,
pledgets of cotton wool, holding tannin en masse,
inserted into the bleeding sockets of the alveoli, will
nearly always eifectually arrest the hemorrhage, by
its astringent action on the vessels, and by its coag-
ulating effect on the albumen of the*escaping blood.
Internal 1}% tannin combinations, are frequently
exhibited in diarrhoea, cholera, and hemorrhage.
Dose 0.06-0.18 Gm. (gr.j-iij.)
R. Acidi Tannic! 4.00 Gm. (.^i).
Glycerins).
Aqua Dest. aa 15.00 fGm (fgss).
M. S. Apply in nursing sore mouth.
The tannins are the active astringent principles
of various vegetable bodies, such as krameria,
catechu, kino, hsematoxylon, hamamelis, or witch-
316 Organic Chemistry.
hazel, and of quercus alba, and other species of
oak. They are denominated glucosides because
like amygdalin, coniferin, salicin, etc., they change
by the action of ferments, or by dilute acids, or
alkalies, into glucose (dextro) and other bodies,
which are mainly derivatives of benzene.
Tannin may be regarded as gallic anhydride.
Tannin. Gallic Acid.
Nitro-benzene, C6H5NO2, is a volatile liquid, used
in making cheap perfumery and flavoring essences.
When nitrobenzene is acted on by nascent hy-
drogen it is changed to j)henylamine, C^H^l^YL^',
also known as amidobenzene, or aniline.
C6H,K02+6H = 2H204-CeH5NH2. '
Nitrobenzine. Aniline.
Aniline is a liquid, slightly heavier than water.
It possesses a smooth disagreeable odor ; is strongly
basic and unites with acids to form salts. It istho
basis of aniline dyes. And thus from the benzene
of coal tar, erstwhile a waste product in the manu-
facture of illuminating gas, comes those splendid
colors, which confer on fabrics of silk, etc., the
elegant shadings now so noticeable.
Trinitrophenol,CQH^ OH^ ^' ^^ ^^^^ known as
picric acid. The picrates are highly explosive salts.
Many derivatives of benzene are used in medi-
Benzene Group. 817
cine, such as salol, a compound of salicylic acid and
phenol; phenacetine, and the analogous com-
pound, acetanilide, Cgll^ — NH — C2H3O2 ; resor-
cin, Cg 114(011)2 ; pyridine, CgH^^; naphthaline,
I I
H— C C C— H
I II I
H— C C /C-H
c c
k k
formulated by
over lapping of two benzine rings; quinicine,
C9H9N2, to which antipyrine, CiiHi2^2^? i^ ^^"
lated, etc.
They are antiseptic, antipyretic, and analgesic ;
and alone, or in various combinations with each
other, or with other drugs, they are effective in
performing the functions assigned.
Their dosage ranges from 0.25 Gm. to 1.00 Gm.
(gr. iv-xvi), and their probable action consists of
destructive deoxidation of protoplasm.
318 , Organic Chemistry.
CHAPTER XIII.
CARBO-HYDRATES.
Carbo-hydrates, so-called, because their molecules
represent H and 0 in the proportion to form water,
united to carbon. They include starchy woody fiber ^
and sugars.
Starch, CgH^oOg, is an important constituent
of the vegetable kingdom, especially in grains,
such as corn, wheat, and rice, and in potatoes. It is
probably formed in the plant, somewhat according
to the following equation :
6CO2 + 5H,0 = CeHioO^ + O^,
Starch consists physically of minute granules,
insoluble in water, but which, when heated with
water to 71° (160F), burst open and form starch
paste. When heated to 205° (400F) starch is
changed to isomeric dextrin^ a soluble substance
used on the sticky surface of postage stamps. The
same isomeric change is produced on starch by cer-
tain dilute acids. Dilute sulphuric acid turns
starch to dextrin, then to glucose. Saliva also pro-
duces a similar change, as does the ferment on the
Carbo- Hydrates. 319
farinaceous mixture in the first stages of alcoholic
fermentation.
The natural gums contain polymers of starch.
Gum-arabic is a combination of potassium and
calcium, with arabic acid -{CqYL^qO^)^. Agar-
agar, or Ceylon moss, used for thickening soups
and jellies, and in cultures for growing microbes;
and other vegetables, as beets and carrots, as well
as many fruits, contain polymers of starch and
dextrin. Animal starch, glycogen^ is found in the
liver and placenta.
Solutions of starch and iodine, when mixed, turn
to blue, by which the presence of starch, as dis-
tinguished from its isomers, may be determined.
Cellulose, CgHjoOg, is the chief constituent of
vegetable liber. Bleached cotton is practically pure
cellulose, as is also linen that has been frequently
laundried, a process which removes the inherent
gums and resins from the surface.
When cellulose is treated with nitric and sul-
phuric acids, NiTRO-CELLULOSE, or guncotton, also
known as pyroxylin, Cgll^ (1^02)305, is produced.
Guncotton is highly explosive.
Celluloid consists of pyroxylin mixed with cam-
l)hor, zinc oxide, and coloring matters, and sub-
jected to pressure while in the pulpy state.
320 Organic Chemistry.
Collodion is obtained by dissolving guncotton in
a mixture of alcohol and ether. When the liquid
collodion evaporates, it leaves a coherent iilm,
known in surgery as a sort of artificial skin. Can-
tharidal collodion, is used with some advantage as
a counter-irritant in periodontitis.
The sugars are divided into two groups, sucroses,
and glucoses.
SucROSES have the formula, Ci2ll2 2^ii? ^^^^ ^'^"
elude cane and beet sugar (sucrose), milk sugar
(lactose), and a variety of starch sugar (mal-
tose), etc.
Glucoses, CgH^2^6? include grape sugar (dex-
trose), SLiid fruit sugar (levulose), etc.
Cane sugar (Sucrose), is obtained from the sugar
cane, sugar beet, sorghum, and sugar maple. It is
a most important article of human diet. When
refined, cane sagar, presents a white crystalline
form, perfectly soluble in water. When heated it
loses part of its aqueous elem.ents, and is converted
into caramel.
Grape sugar (Glucose) exists in many sweet
fruits, and m honey ; it occurs also as a concomi-
tant in the disease known as diabetes.
Glucose IS largely produced artificially, by action
of dilute sulphuric acid upon corn starch. It is
Carbo- Hydrates. 321
used extensively as a substitute for cane sugar, being
cheaper, in the making of syrups, and candies; and
on account of its ability to ferment, in the produc-
tion of beer and ale.
322 Organic Chemistry.
CHAPTER XIV.
TERPENES, ETC.
The Terpenes, C^ oHj g, are homologous v^iihjpen-
tone, CgHg, having the general formula CnH2n — 4 ;
and areisologous with decane, CjqH22- They exist
in the volatile or essential oils of certain trees and
plants, especially of the coniferous and aurantia-
ceous orders. They have not as yet been produced
artificially, although some of them are structurally
related to benzene.
Their formula is isomeric with decone, C^oH^g,
and are regarded as tetrad radicals ; although ap-
parently satisfied, they are capable of taking up
two molecules of HCl. If the molecule, C^oHjg,
be doubled, the polymer, C20H32, as in the case of
2 atoms of carbon, — C — C — , loses 2 units of
I I
valency, and becomes a hexad.
Cologne is an alcoholic solution of certain essen-
tial oils.
Turpentine Oil, Oleum Terebinthince, C^oH^g, is
the most familiar representative of the terpenes. It
is obtained by distilling the juices which exude
Terpenes, etc. 323
from cuts in the bodies of several species of the
genus jpine. The commercial variety contains some
admixture of other hydrocarbons, and traces of
oxidation products.
Rosin which remains in the retort, consists essen-
tially of silvic acid, Cj9H2 9COOH.
Other resins, such as shellac, copal, sandarac, etc.,
are rosins, obtained similarly from various terpenes
by distillation, or as the exudate from various
kinds of trees.
The terpenes are disposed to absorb oxygen from
the air, and thus pass into camphors.
That many volatile oils isomeric with oil of tur-
pentine, such as oil of neroli, bergamot, cloves,
pepper, caraway, lemon, etc., should exhibit such
diversity of physical properties, is a problem which
stereo-chemistry will doubtless be able to explain
satisfactorily, in t4ie near future.
The antiseptic, and disinfectant, properties of the
terpenes (essential oils) are in all probability due
to their power of taking up oxygen from the air,
by which two atoms of hydrogen are removed,
resulting in CioHj404, a highly oxidized hydro-
carbon, which with moisture, and summer-heat,
developes nascent oxygen.
C,„II,,0,+2H,0 = H,0,+CioH,,0,.
Oxygenated Hydrogen Camphoric
Terpene. Dioxide. Acid.
324 Organic Chemistry.
Materia Medica. — Although many of the essen-
tial oils (especially that of cloves), have been,
from time immemorial, favorite domestic remedies
afi^ainst toothache; and in practice, as ingredients
of pulp capphigs, their introduction as disinfectant,
and antiseptic dressings, in root canals, is mainly
due to Drs. Harlan, Black and Barrett.
Oil of Cloves, oleum caryophilli, is obtained by
distilling the dried buds (cloves) of an evergreen
tree of the myrtle order, Eugenia caryophillata. The
oil consists of caryophillin, CjoH^g, and an oxygen
oil, eugenol, or eugenic acid, CgH^jCOOH. When
fresh it is colorless, but by exposure, becomes yel-
low, and finally, reddish-brown. It possesses a
strong fragrant odor, and a hot aromatic taste; is
nearly insoluble in water, but freely soluble in alco-
hol. When mixed in small proportion with either
carbolic acid, or creasote, it eflectually masks their
peculiar odors. If applied to irritable dental pulp,
in odontalgia, it reduces sensibility by its power
of extra stimulation, and as a dressing in root ca-
nals, by its diffusion through the tubuli, and its
ultimate reduction to a camphor, prevents a return
of the process of putrefaction in the part and the
consequent pathological sequelae.
It is frequently exhibited internally as an anti-
Terpenes, etc, 325
spasmodic stimulant, in flatulent colic, nausea, and
vomiting.
Dose, 0.12-0.30 fGm. (nt ij-v)
Oil of Sassafras is obtained oy distilling the
bark and wood of the root of the sassafras offici-
nallis, a native tree, of the genus laurel. The oil
has a pleasant odor, a warm pungent aromatic taste ;
oxidized by cold nitric acid, it is converted into a
red resin. It is an excellent germicide, and is one
of the ingredients of "sarsaparilla" syrup. The
aqueous infusion of sassafras root bark is a popular
"tea" and "blood purifier." Sassafras possesses
mild astringent, stimulant alterative and diapho-
retic properties. The powdered root, mixed with
" chewing gum," and used as a masticatory, is a
good adjunct in the treatment of alveolar py-
orrhoea.
Dose of the oil, 0.06-0.25 fGm. (n^ j-iv)
Oil of Cinnamon, oleum cinnimomi, is obtained
from the inner bark of the shoots of the cinnimo-
mum zeylanicum (cassia), trees of the natural order
Lauracese, growing In China, Ceylon, and adjacent
countries. The Ceylon variety is the most es-
teemed.
The oil is somewhat heavier than water ; of an
agreeable odor, and a very hot penetrating taste.
It is a powerful local stimulant, and when applied
326 Organic Chemistry.
to an aching dental pulp, relieves the pain. It is
also a diffusive disinfectant and antiseptic, and is
employed as such, preparatory to filling root ca-
nals. On exposure, the oil of cassia tends to de-
velop cinnamic acid (phenyl-acrylic acid,
CfiHg - CH = CH - COOH).
The properties of cinnamon, as a sialogogue,
stimulant, astringent carminative, and uterine he-
mostatic, when taken internally, is due to its con-
tained oil and resin, and some tannic and cinna-
mic acids.
Dose of the oil, 0.06-0.30 fGm. (j\ g-v)
Ter penes y etc. 327
CHAPTER XV.
TERPENES, ETC.— (Continued).
Oil of Wintergreen, oleum Gaultheria, from the
leaves of the indigenous evergreen plant, Gaultheria
procumbens, or Partridge-berry ; it exists also in the
sweet birch, and other plants, and is largely composed
of methyl salicylate CHgC^H^Og. It is the heaviest
of the essential oils, and is largely used for flavor-
ing; its principal use in dentistry is to disguise the
disagreeable tastes and odors of other certain drugs,
albeit it is itself an excellent antiseptic. It is em-
ployed internally in rheumatic disorders, as a pleas-
ant substitute for salicylic acid. A cold "• tea " of
the leaves of the plant, is a popular astringent,
carminative, and emmenagogue.
Dose of the oil 0.20-0.60 fGm. (ni iij-x.)
Oil of Eucalyptus, oleum Eucalypti, from the
leaves of the matured Eucalyptus Globulus, or blue
gum tree, a native of Australia, but now grown to
some extent, in Italy, California, etc. The oil has
a pleasant aromatic odor, a pungent somewhat cam-
328 Organic Chemistry.
phoraceous, cooling taste; it is composed of terpene,
C10H16. cymene,
CioHi4=(C6H4<ci'-CH,-CH3)
and eucalyptol, CjqH^5(0H). It exhibits a destruc-
tive influence on microbic forms of animal and
vegetable life.
Alone or combined with other antiseptics, it is
eftective in treatment of suppurating pulps, oral
ulcerations, pyorrhoea, and chronic alveolar abscess.
It is a solvent for gutta percha.
Internally administered, the preparations of eu-
calyptus, act as a stimulent to the brain and nervous
system; they increase the circulation, and respira-
tion, and a re sialogogue, and diaphoretic; and tonic
in gastric dyspepsia.
Dose of oil 0.30-2.00 fGm. (nv-xxx.)
Dose of tincture 2.00-8.00 fGm. (fSss-ij.)
B. Olei eucalypti.
Acidi carbolici aa 6.00 fGm. (f^jss.)
Olei Gaultheria 2.00 fGm. (f^ss.)
M. S. Apply by syringe, in pyorrhoea (Dr. G. V. Black,
from (jorgas.)
Oil of Caraway, oleum cari, is obtained from the
fruit of a European plant, the Carum Carvi. Its
odor is aromatic, and its taste acrid. It consists of
Ter penes, Phenols, etc. 329
the terpene, carvene O^QH^g, and the ten carbon
phenol, carvol, C^oHjgOH.
Dose of the oil 0.06-0.30 fGm. ("I j-v.)
Carvacrol, CjQH^gOH, is isomeric, and probably-
identical with carvol. It has a taste, persistent
and strongly acrid, and a creasotic odor. It is a
solvent for gutta percha. Is disinfectant and anti-
septic ; and is analgesic, and escharotic on sensitive
dentine.
Its principal source is oil of caraway.
Dose, not used internally.
Thymol, C ^ qH ^ 3(0H), is Isomeric with carvacrol.
It is a constituent of the volatile oil of the garden
plant, Thymus vulgaris, and of several other
phmts. The isomeric relation of thymol, to carva-
crol, may be most easily understood by the benzene
hat-rack,
I I
H-C^ C— OH H— C^ C-H
H— C
n— H H— a £—011
Carvacrol. Thymol.
Both are methyl-propyl-phenols. In carvacrol the
28
330 Organic Chemistry.
methyl group (CHg) stands to the hydroxyl group
(OH) in the or^Ao-position, and in thymol, in the
977 e^a- position.
Thymol crystallizes in transparant plates, of a
mild pleasant odor, and peppery taste. It is prac-
tically insoluble in water, but is freely soluble in
alcohol, chloroform, and ether, and liquefies with
camphor, and chloral alkalies. It forms, with glyc-
erine, a good antiseptic.
Aristol, CioHi3(OI), is obtained from an alka-
line solution of thymol, by adding potassium
iodide solution of iodine, by which is produced a
red-brown amorphous precipitate, consisting of
thymol, minus its hydroxjdlic H, plus I, and may
be chemically known as thymol lodroxide.
Aristol occurs in impalpable powder, almost
tasteless and odorless. It is insoluble in water,
glycerine, alcohol, and alkalies, but freely soluble
in chloroform and ether, and is readily decomposed
by light and heat.
Its insolubility in water enables it to act as an
antiseptic, by preventing egress to the part, of
septic germs ; and as a germicide, by the free
iodine, which it slowly gives off, at the tempera-
ture of the mouth.
Cotton wool, holding a saturated solution of
Terpenes, Phenols, etc. 331
aristol in chloroform, or ether, placed between
teeth or over dressings in their cavities, will re-
main comparatively odorless for indefinite periods
of time.
Dose — Not used internally.
332 Organic Chemistry,
CHAPTER XYI.
TERPENES, PHENOLS, ETC.— (Continued.)
Resorcin, CgH4(OH)2, as may be presumed from
its formula, is closely related to carbolic acid. It
is a diatomic phenol, obtained by fusing caustic al-
kalies with certain gums, as galbanum, or with po-
tassium-benzol-disulphonate. By the latter pro-
cess resorcin and potassium sulphite result.
Rosorcin occurs in prismatic shining crystals, of
a sweetish pungent taste, freely soluble in water,
less so in alcohol, ether, and glycerine, and not at
all in chloroform. It is not so caustic and irri-
tating as carbolic acid, although in strong solution
it is fully as good an antiseptic. It is preferred to
carbolic acid as an internal antiseptic and antipy-
retic, being less poisonous.
Dose, 0.30 Gm. (gr. v)
Oil of Peppermint, oleum menthce piperitm, ob-
tained by distilling the fresh leaves of the plant.
It consists of a terpene and a mon atomic alcohol,
the latter called menthol, CiqHj9(0H); also known
as peppermint camphor.
Terpenes, Phenols, etc. 338
Menthol, applied locally, is a non-corrosive vas-
cular stimulant, antiseptic, and anaesthetic.
Pyrethrum, Pellitory ; the root furnishes an oil
which, applied in ethereal solution, relieves adon-
talgia. The flowers of Persian pellitory are used
as " insect powder."
Oil of Orange Flowers, oleum neroli, is of de-
lightfully fragrant odor.
Caoutchouc, India-rubber, is a thickened gum
of the milky juice of several trees, as Euphorbia,
growing in tropical countries. Para gum, shipped
from Para, on the Amazon, is the most highly
prized. Caoutchouc consists essentially of a mix-
ture of terpenes, isomeric or polymeric, with oil of
turpentine (C^oH'^g). It softens by heat; is not
soluble in water or alcohol, but dissolves in chloro-
form, pure ether, turpentine, benzene, and carbon
disulphide. Mixed in variable proportions with
sulphur, and heated, it becomes vulcanized India
rubber. With one-half its weight of sulphur, ebonite
is formed. Coloring matters are also often added,
as Vermillion (Hg2S), to give it a red color; white
clay and zinc oxide, to produce white rubber, etc.
Gutta-percha is the hardened juice of the iso-
nandra percha tree, growing in Malacca and adjacent
islands. It resembles caoutchouc in many re-
spects, being insalubla. lu. w.atex,. aud capable of
334 Organic Chemistry.
vulcanizing with sulphur. It is less elastic than
rubber, and is a very poor conductor of electricity,
hence it is extensively used as an electric insulator.
Gutta-percha, mixed with zinc, oxide, is used as a
" filling " material, and retains its identity in the
teeth against chemical action, but soon succumbs
to active attrition.
IS'aphthaline, CjoHg, is a product of the distil-
lation of coal-tar. It occurs in large white crys-
tals of tarry odor and somewhat aromatic taste ;
insoluble in water and in dilute acid and alkaline
solutions, but soluble in chloroform, ether, volatile
and fixed oils, benzene, and hot alcohol. It is a
valuable antiseptic; combined with iodoform it
forms an excellent dressing in root canals.
Hydronaphthol, C^qH^OH, derived from naph-
thaline, crystallizes in shiny white scales, sparingly
soluble in water, freely soluble in alcohol, glyc-
erine, etc. It is non-poisonous, but is an excel-
lent germicide and antiseptic in dental practice,
and is also favorably exhibited as such, in general
practice, especially in ailments of the intestinal
canal.
HesinSy Camphors^ etc. 335
CHAPTER XVII.
RESINS, CAMPHORS, ETC.
Myrrh is a fair representative of gum resins. It
is an exudate from the stems of the Balsomodendron
myrrha, a small tree of South-western Asia and
I^orthern Africa. When comparatively pure, it
comes to us in semi-transparent yellow-reddish
tears, held together in considerable bulk, of agree-
able odor and aromatic bitter taste. It may be
pulverized, and is soluble in ether and alcohol. It
is a mild stimulant astriiigent to mucous surfaces,
and is an effective application in the form of pow-
der or tincture, to relaxed ulcerated conditions of
the gums and throat.
Dose of the tincture, 2.00-4.00 fGm. (fess-i)
K. Aluminis, .... 4.00 Gm. (^i)
Tincture Myrrhse, . . 8.00 fGm. (f^ij)
Infusi Rosse comp. . . 160.00 fGm. (f^v)
M. S. Use as a gargle.
(Modified from Farquharson.)
Camphor, C^oII^gO, common camphor, (like other
camphors, such as caryophillin, 02 0113 2 0^), may
be regarded as an okyK^v''?'t.c>d''^^rp'feii.f,\ Closely re-
• • • • • •
' • • • • • •
' • • • • • t
I • • • • • • •
• • • • • < •
336
Organic Chemistry.
lated to these, are many solid and liquid camphors
which react as alcohols or stearoptenes, such as
Borneol, or Borneo camphor, C^qH^-^OII, and its
homologue, patchouli camphor, C^ 5 II 2 7 OH, menthol,
or mint camphor, C ^ q II ^ 9 OH, absinthol, C ^^ q H ^ 5 OH,
etc. Camphors are also obtained from the volatile
oils of many plants, such as the oils of lavender,
cajeput, orange, rosemary, coriander, hops, marjo-
ram, etc., etc. By reaction with strong oxidizing
agencies, such as nitric acid, ozone, etc., they are
changed into acid com[)Ounds, of which camphoric
acid, CgH^ 4(00011)2, is a fair representative.
The chemical relation between camphor, which
is a ketone, and Borneol, which is a monatomic al-
cohol, and camphoric acid, may be differentiated by
erecting them in graphic formulae, thus :
CH,
CH
H— C^ C=C=.0
\ / 2
C-H
H-C^ C— 0-H
H^^C C=:H2
C-H
C3H,
Camphor.
C3H7
Borneol.
c »
e «•
t c <
I
liesinSj Camphors y etc. 337
3
PH
11— C' ^C— 0
,4
H2=C C— 0
C-II OH
C3H7
Camphoric Acid.
Common camphor is obtained in a crude way
by distilling with water the, wood of the Laurus
camphora tree of South-eastern Asia. It is a col-
orless translucent solid, of sp. gr. 0.935 ; of a pen-
etrating, aromatic odor, and rather unpleasant
taste ; sparingly soluble in water, but freely soluble
in volatile oils, strong acetic acid, ether and alco-
hol. Pieces of camphor thrown on water, show
the high volatility of the substance by the vapor
pressure on the water, causing a rotatory motion of
the granules; if they be covered with oil, which
prevents evaporation of the camphor, rotation in
water will not occur.
Camphor is an important ingredient of many
liniments in common use. When locally applied,
it exhibits irritant, rubefacient, and finally, ano-
dyne properties. ComVjined with chloral, or in
strong solution with chloroform, it is an effective
local anaesthetic, and i^ lused ^s euch in obtunding
29
J J J >
338 Organic Chemistry.
sensitive dentine^ exposed dental nerce^ and in al-
laying the pain which often follows the extraction
of teeth.
Internally administered, camphor is strongly an-
tispasmodic, diaphoretic and anaphrodisiac. In
large dose it is narcotic and depressant, but in
small doses it is mildly stimulant and diaphoretic.
Dose, 0.06-0.60 Gm. (grj-x)
Chloral camphor is a liquid obtained by triturat-
ing together equal weights of chloral hydrate and
camphor. The mixture exhibits antiseptic and ob-
tunding properties, and is a good solvent for many
alkaloids.
Compho-phenic, as its name implies, is a combi-
nation of camphor and carbolic acid. It is non-
caustic and non-irritant, and is antiseptic and
somewhat anaesthetic when applied to sensitive in-
flamed surfaces.
R. Camphora —
Chloral hydratis, aa, 16.00 Gra. (giv)
Etheris sulph. 30.00 fGm. (fgi)
M. S. For office use.
Capsicum, cayenne pepper, is the fruit of the plant
capsicum fastigiatum. It possesses a peculiar odor
and very hot taste, and contains capsicin, the active
principle and a volatile alkaloid.
Resins, Camphors, etc. 389
Capsicum is one of the most familiar of local
irritants. They produce on the part, a vascular ex-
citement which oftentimes modifies the pain of
coming inflammation. Hence capsicum, as well as
the fruit of the piper nigrum (black pepper), etc.,
are severally, and combined, employed in plaster
form to prevent the painful development of ex-
pectant periodontitis, subsequent to the operation
of tilling root canals.
HuMULUS, Hops, the fruit cones, (strobiles,) of the
common hop-vine, (humulus lupulus). The glandu-
lar portion of the strobiles consist of irregularly
rounded small grains, of a yellow color, known as
lupulin, which contains also, in most abundance,
waxy resins and tannin, and a volatile oil, consist-
ing of trimethylamine (valerol, and lupulinic acid.
Hops are mildly hypnotic, tonic, and somewhat
astringent. They increase cutaneous circulation,
when externally applied, followed by a soothing
influence on sensory nerves. A calming efl'ect is
produced on localized inflammation, such as acute
alveolar abscess, by a warm hop poultice, external
to the part.
Dose of Lupulin, 0.30-0.90 Gni. (gr. v-xv.)
Calendula, the fresh flowering garden marigold,
furnishes a tincture which possesses a stmiulant
S40 Organic Chemistry.
resolvent power, and which when applied to ex-
posed pulp, or in alveolar sockets, after extraction
of teeth, impresses itself favorably, by relieving in
a large measure, the consequent pain.
>--.yl
Alkaloids. 341
CHAPTER XVIII.
NATURAL ALKALOIDS.
Alkaloids are organic bases capable of uniting
with acids to form salts. Many of them exist in
union with characteristic acids, in certain vegetable
products ; they also occur in animal bodies, as
leucomaines ; and as a result of putrefaction, as
ptomaines. They are mostly poisons, are closely
related to the artificial amines^ and contain !N^ as an
essential element.
Those that are made up of C, H, and I^, as
nicotine, CjqHj4]N'2, etc., are generally volatile
liquids; while those which also contain 0, as
Caffeine, CgH ^^fi^^ Morphine, C^^H^glN'Oj,
etc., are non-volatile solids.
^h.Q\r graphic formulas are not as yet determined.
When uniting with acids to form salts, they behave
like ammonia; the hydrogen of the acid is not set
free, thus differing in interaction with acids, from
the general effect produced by metals.
(NH3), + H2SO4 = (NH,).,SO,.
Ammonia. Am. Sulphate.
C,,HigN03 + H2SO4 = C,,1I^3N03H2S04.
Morphia. Morph. Sulphate.
Zn + H2SO4 = ZnS04 + II,.
Zn Sulphate.
342 Organic Chemistry.
Their names terminate in either ine or ia accord-
ing to preference. As a rule, they are less soluble
in water, than are their salts.
Quinine, quinia, 02 0112 4^2 02,3112 0, is the most
highly prized active principle of Cinchona bark.
The genus cinchona comprise many species.
They were named in honor of the Countess of
Cinchon who was cured of a relapsing fever by
infusions of the bark, sent her by the Jesuit Mis-
sionaries in Peru.
Cinchona trees flourish mainly on the eastern
slope of the Andes, between the 20th degree S.
latitude, and the 10th degree N. latitude. They are
now profitably cultivated in India, and in southern
Asiatic islands.
Three varieties of cinchona bark are sufficient
representatives of the entire genus.
1. C. Calisaya, C. Flava, yellow bark.
2. 0. SucciRUBA, red bark.
3. C. Pallida, pale bark.
Different cinchona barks contain variable quan-
tities of numerous active medicinal alkaloids, of
which quinia and cinchona are the most valuable.
They exist in the bark, in union with kinic or quinic^
(monobasic pentatomic) acid, CgH7(OH)4COOH.
Quinine is separated from the bark, and the kinic
acid, by dilute hydrochloric acid, which forms the
Alkaloids. 343
soluble quinia hydrochloride. By the addition of
lime, calcium chloride is formed, taking thus from
the quinia, the hydrochloric acid, and compelling
the alkaloid to precipitate. This precipitate is
washed in water, and taken up by boiling alcohol,
which is afterward set free by distillation.
Quinine occurs as a white amorphous crystalline
powder, inodorous, but of an exceedingly bitter
taste; very sparingly soluble in water; freely sol-
uble in hot alcohol, chloroform, ether, and the
fixed and essential oils ; is alkaline in reaction and
forms salts with acids, of which the sulphate is the
most generally employed, and which has appropri-
ated the name, quinine.
Quinia sulphate, (0201^24^2^2)2) HgSO^jSHgO,
quinine, is rarely used locally.
In small doses, internally administered, it acts
as a tonic, an antiseptic, and antiperiodic. In full
doses it causes anemia of the brain, accompanied
by ringing in the ears (cinchonism), partial deaf-
ness and blindness, and frontal headache.
It reduces the reflex irritability of the spinal
chord. At first it increases, and afterward slows
the heart's action. It increases the number of
white corpuscles, but prevents their amoeboid move-
ments, and prevents, also, the due giving up of 0
to the tissues. For this latter influence, quinine
344 Organic Chemistry.
might be suggested internally in localized inflam-
mation, such as acute alveolar abcess. It has but
slight effect on the temperature of the body in full
health ; but in fevers^ the temperature is dimin-
ished by quinine.
Dose, 0.12-1.25 Gm. (grij-xx)
B Quinia sulphalis, 1.00 Gin. (grxv)
Ft. capsules, No. 5.
S. Take one every two (2) hours.
(In either acute alveolar abcess or periodic supra-
orbital neuralgia.)
Artificial substitutes for quinine are being rap-
idly introduced by manufacturers. They are gen-
erally of coal-tar origin, and belong to the ben-
zene series, either directly, or as substitution pro-
ducts. Some of them have been alluded to on
page 316. They also possess active analgesic, germ-
icidal and antiseptic properties. Of these com-
pounds, Pyoktanine, methyl violet, is the one most
used in dentistry, as an antiseptic dressing in root
canals, but is objectionable as such, on account of
its coloring influence on dentine. It is a violet
blue powder, odorless, non-poisonous, sparingly
soluble in water and alcohol, insoluble in ether,
and very diffusible in animal fluids.
Alkaloids. 345
CHAPTER XIX.
ALKALOIDS— (Continued).
Morphine, Morphia, Ci^H^gl^Og, is the principal
individual of the many active alkaloids found in
opium.
Opium is the inspissated juice of the unripe cap-
sules of the papaver. somniferum, or white (or black)
poppy, indigenous to Asia Minor, and cultivated
extensively in other countries. The poppy is an
annual plant, growing from 2 to 3 feet high. The
milky juice obtained from incisions in the capsules
(poppy heads), becomes concrete by exposure to
the air, and comes to us, in irregularly rounded or
flattened cakes, of a brown color, strong narcotic
odor, and bitter taste, exciting to salivation. It
yields its numerous virtues to water, and alcohol,
and dilute acids, but not to ether.
Morphine exists in opium in union withmeconic
acid, CgllgOgCOOH. The favorite salt of mor-
phine, is the sulp hate y (C^ 71119^03)2, H2SO45H2O,
soluble in water and alcohol, but not in chloroform
or ether. Consists of w4iite flocculent crystals, of
bitter taste; is less astringent and diaphoretic than
opium, but possesses greater power as a hypnotic
346 Organic Chemistry.
and anodyne. Morphine is not regarded with much
favor as a local anodyne; but if it be injected in
solution hypodermatically, or taken by way of the
primce vice, it exhibits the most distinguished nar-
cotic properties. At first, the brain is gently ex-
cited, as with opium, followed by a soothing seda-
tive eflect ; and sleep ensues, induced by cerebral
anemia. Awakening is accompanied by headache,
digestive disturbance, and (with opiura)constipation.
Subcutaneous injection of.
Morphia 0.01 Gm. (gr.f )
Aqua Dest. 1.00 fGm. (rn,xv) M.,
will relieve the exceeding pain of periodontitis.
Coffee and Belladonna, or their most active
alkaloids, caffeine and atropine, are the principal
physiological antidotes to morphine.
Dose of Morphine, 0.01-0.02 Gm. (gr.i-|.)
Dose of Opium, 0.06 Gm. (gr. j.)
Dose of Tinctura opii, 1.00 fGm. (n^^xv.)
Dose of Tinctura opii et camphorata, 4.00 fGm. (f^i.)
Cocaine, is obtained fi?om the leaves of Erythroxy-
lon Coca, a small plant, indigenous to the mountain-
ous portions of Peru and Bolivia, and now exten-
sively cultivated elsewhere. The leaves have been
used from time immemorial as a masticatory, by
the natives of those countries, by aid of which,
they are enabled to undergo fatiguing labor, with
Alkaloids. 347
apparent impunity, through the obtunding influence
on the sensory nerves, and loss of the sensations of
hunger, and thirst, produced by the drug.
Cocaine is a univalent base of alkaline reaction,
and has the empirical formula, C17H21NO4. It
forms with acids, neutcal salts, of which the Hy-
drochloride (vide '' nomenclature " in Part first) is
the most useful.
The distinction which cocaine hydrochloride has
assumed as a local anaesthetic is well deserved.
Applied to the mucous membrane, or ocular con-
junctiva, or injected hypodermatically (hypoder-
mically) in other parts, it causes profound aneesthesia
over a limited area, sufficient for minor surgical
operations. ^It causes thus, local anemia, by which
probably the sensory nerves, are rendered unable
to transmit normal impressions.
Cocaine hydrochloride, C17H19NO4, HCI2H2O,
occurs as colorless small prismatic crystals, soluble
in alcohol, water, chloroform, and vaseline, but not
in ether. It is odorless, but possesses a bitter taste,
followed by loss of the sense of taste, through its
paralyzing influence on the peripheral extremities
of the gustatory nerve.
0.65 f Gm. (rrix) of the 5 per cent, aqueous solu-
tion injected into the immediate neighborhood of
the apex of root, will develope sufficient local
348 Organic Chemistry.
anaesthesia to permit the painless extraction of the
tooth. One of the best stimulants in collapse, which
some times supervenes after the operation, is Hoff-
man's Anodyne (Spiritus ^theris) in half teaspoon-
ful doses, and also if necessary, subcutaneous in-
jection of Atropine.
Aqueous solution of cocaine hydrochloride should
be fresh, as it tends to rapidly deteriorate by fer-
mentation; to overcome this latter difficulty, small
proportions of salicylic acid, or carbolic acid, are
added; and also as physiological antidotes, either
atropine, or chloroform.
Various combinations of cocaine with other
drugs, have been patented as local anaesthetics, and
given suggestive names, by which coftfiding mem-
bers of the profession are being extensively imposed
upon. Practitioners, worthy of the name, should
be possessed of more self respect than is indicated
by the encouragement many of them extend to the
mercenary aspect of such secret nostrums.
Cocaine is a cerebral stimulant ; it also excites
the general nervous system, and increases cardiac,
and respiratory movement. In small doses it is a
tonic and diuretic. In Lethal doses, death occurs
by simultaneous cardiac and respiratory failure.
Dose— 0.01 - 0.06 Gm. (gr. -H).
Alkaloids, etc. 349
R. Cocnina Hydrochloric 1.00 Grri. (gr, xv).
Atropia Sulphas 0.01 Gm. (gr. |-).
Aridi Carbullci (cryst.) 0.25 Gm. (gr. iv).
Chloral Hydratis 0.20 Gm. (gr. iij).
Aqua Dest. Ad. 32.00 fGin. (f^i).
M. For extraction of tooth, inject 1.00 fGm. (rrt^xv).
(Modified from formula given in " Transactions of Kan-
sas D. A.")
R. Cocaina phenatis 0.10 Gm. (gr. jss).
Alcoholis (ad solve) 4.00 fGm. (fsi).
Aqua Dest. 6.00 fGm. (fsjss).
M. Six (6) Injections.
U. Cocaina Hydrochloris (cryst). Insert in moist cav-
ity, and let remain ten minutes; for sensitive
dentine.
R. Cocaina Hydrochloris 0.10 Gm. (gr. jss).
Alcoholis, Chloroform! aa 4.00 fGm. (f^i).
M. Apply to Gum as a local anaesthetic (Dr. H. J. McKel-
lop, from Gorgas).
350 Organic Chemistry.
CHAPTER XX.
ALKALOIDS, ETC.
AcoNiTiNE, Cg3H4 3]SrOi2?is the active alkaloid of
the leaves and root of the Anconitum Napellus, or
monkshood, a perennial plant, indigenous to the
mountainous portions of Europe. The leaves are
deeply divided; the flowers of a purple blue color,
and of bell-shaped pendant form. All parts of
the plant possess medicinal bitter properties, but
the root is richest in active principles. Tinctura
aconiti radicis is the most favored preparation.
Tincture of aconite, applied locally, causes
a tingling, burning sensation, followed by numb-
ness, due probably, to the paralyzing influence of
aconite on the extremities of the sensory nerves.
It produces sedative and anodyne effects when
used topically in neuralgia and rheumatism, and
relieves the pain of acute periodontitis.
When taken internally, even in full doses, aco-
nite does not interfere with the normal intellectual
faculties of the brain. The reflex irritability of
the spinal chord is greatly diminished, cardiac ac-
tion, respiratory movement, and temperature are
Alkaloids, etc. 351
reduced. It increases the flow of saliva and the
secretions of the skin and kidneys.
On account of excessive slowing of the heart's
action by aconite, its eraploymeut should be
avoided in cases of suspected cardiac weakness.
Antidotes : Emetic, animal charcoal pulv. Tannin, hot
alcoholic stimulapts, and digitalis ; also, arayl nitrite.
Dose, tincture of the root, 0.06-0.30 fGm. (^^ij-v)
" Aconitine, . . . 0.001 Gm. (gr. -J^)
Atropine, Cj7H23]Sr03, is the active medicinal
principle of the root and leaves of atrop a belladonna,
or deadly nightshade, sl perennial herbaceous plant,
natural to the mountainous regions of Southern
Europe and Asia, but now cultivated in this coun-
try and elsewhere.
Atropine Sulphate (0^711231^03)2112804, is much
more soluble in water than is the alkaloid. It is
also freely soluble in alcohol, but not in ether. It
is neutral in reaction, without odor, and of a bitter
taste, and like aconitine, very poisonous.
Topical application of belladonna preparations
is soothing and anodyne in neuralgic pains and in
abcesses, and is efficacious in reducing or arresting
suppurative processes, localized perspiration and
the secretion of the mammary glands. Taken in-
ternally, belladonna causes gentle hallucinations of
a joyful character, and calming sleep. The reflex
352 Organic Chemistry.
irritability of the spinal chord is diminished, but
cardiac and respiratory movements are increased.
These latter phenomena are supposed to be due
to paralysis of the pneumogastric nerve ; which
condition permits the sympathetic nerves to come
into full play, ungoverned for the time being, by the
pneumogastric, and thus exert their peculiar power.
Belladonna therefore is a temporary cardiac tonic.
It induces dilatation of the pupil, by its paralyz-
ing influence on the raotor-oculi nerve, which sup-
plies the sphincter muscular filaments of the iris,
allowing the sjunpathetic, which rules over the
radiating fibers, to become extra-active in the
performance of its usual function. Belladonna,
checks the secretion of saliva, by selective influence
on the secretory branches of the chorda tympani
nerve, supplied to the submaxillary ganglion.
Antidote: Animal charcoal, vegetable astrin-
gents, opium, calabar bean (physostigma veneno-
sum), and tartar emetic.
Dose, Astropine 0.001 Gm. (gr. -g*^.)
Dose, Fluid Extract of root 0.06-0.30 fGm. ^Mlj-v.)
R. Extractum Bellad. fluidum Rad.
Tinctura Aconiti Radicis aa 8.00 fGm. (^ij.)
Acidi Carbolici 0.30 fGm. (gttv.)
Chloroformi 30.00 fGm. (fgi.)
M. S. Poison. Use as a liniment only, in painful restricted
inflammation.
Alkaloids, etc. 353
Hyoscyamine, the principal alkaloid from the
leaves of Hyoscyamus Niger (Henbane) a biennial
plant, and Daturine from the leaves and seed of
Datura Stramoniam, are chemically identical with
Atropine, and possesses like the latter anodyne and
antisposmodic properties.
The Datura Stramonium plant, also known as
Thornapple and Jimson (Jamestown) weed, is an
annual of common occurrence.
A poultice oi jimson leaves, is very efficacious
in reducing the pain and swelling, in acute alveolar
abscess.
Cannabin, is the most active principle of cannabis
saliva or Hemp, [Cannabis Indica and C. Americana),
Cannabis sativa must not be confounded with
Ajpocynum Cannabinura " Canadian , or Indian
Hemp," the common Milkweed.
Cannabis sativa furnishes several preparations of
more or less mystical importance.
Gunjah is the dried female flowers and leaves,
sold for smoking purposes. Churrus is a resinous
substance obtained by rubbing together the leaves
of the plant ; and Hasheesh, or bhang, consists of
the small broken stalks and leaves, mixed with
aromatics and fruits.
Preparations of Cannibis Sativa taken in full
dose, cause an exalted intoxication, and loss of
30
354 Organic Chemistry.
conception of time, followed by sleep, and great
depression ; they act in moderate doses, as antispas-
modics, and aphrodisiacs.
Applications of warm Tindura Cannabis Indica.
(Dose, 2.00-4.00 fGm. (n|^xxx-lx) has been sug-
gested as a local anaesthetic, in the operation of
extracting teeth.
Hamamelis Vrrginica, or Witch Hazel, is a native
shrub, from the bark and leaves off which, a fluid
extract is obtained, possessed of tonic, astringent,
and anodyne properties.
Dose of the Fluid Extract 0.06-4.00 fGm. (ntj-lx.)
R. Extractum Hamaraelidis Fluidum 4.00 fGm. (f^j.)
Aqua Dest. q. s. Ad. 30.00 fGm. (fgj.)
M. S. An excellent lotion to sore gums, afte- removing
salivary calculus.
Numbers of new remedies belonging mainly to
the " Antiseptic " class, have been introduced during
the present year.
They are generally termed by their manufac-
turers, " Synthetic " (better, J.r^i^ciaQ, preparations,
to distinguish them from natural products. Their
names are sometimes quite fanciful; two at least,
of which are ridiculously similar in sound and
orthography, i. e., Europhen and Euphorin. The
first is probably named in honor of Europe, and the
other in recognition of the genus Euphorbia tree,
Alkalies, etc. 355
from one of the species of which, our Rubber is
obtained.
EuROPHEN occurs as a jellow tasteless, odorous
powder, insoluble in water, and glycerine, but solu-
ble in ether, alcohol, and chloroform.
Locally, it is anaesthetic, and antiseptic, and pre-
sumes to act as a substitute for Iodoform, being less
poisonous, and decidedly of less unpleasant odor.
It is prepared by dehydrating Isobutyl alcohol and
ortho-cresol, by zinc chloride, resulting in isobutyl-
orthocresol, which, dissolved in alkali, and acted
upon by solution of iodine in potassium iodide, pre-
cipitates as Europhen. It consists of hydro-carbon
radicals, about 72 per cent, and of iodine 28 per
cent, while iodoform is made up of hydro-carbon, 3
per cent and of iodine, 97 per cent.
Europhen is, therefore, comparatively very weak
in iodine, which fact, however, need not prevent the
manifestation of the virtues ascribed to it, inasmuch
as the action of any drug, local or general, does not
necessarily depend on its chemical decomposition.
EuPHORiN is a crystalline, substance structurally
related to carbolic acid, and acetanilide, and is
therefore easily erected on the benzene ring. It is
insoluble in water, but dissolves in alcohol, and is
recommended internally, as an effective anti-pyretic,
and analgesic.
356 Organic Chemistry.
AsAPROL is a crystalline substance, and Diaph-
THERiN, is an amorphous powder. Both are soluble
in water, and possess active germicidal, and anti-
septic properties.
Analysis of Teeth (Berzelius) :
Organic substance 28.0
Calcium phosphate 64.4
Calcium carbonate 5.3
Magnesium phosphate 1.0
Sodium carbonate and chloride 1.3
100.0
(Fremy).
Ash. Calcium Phos. Mag. Phos. Cal. Garb.
Enamel, 96.9 90.5 traces. 2.2
Dentine, 76.8 70.3 4.3 2.2
Cement, 67.1 60.7 1.2 2.9
[ Taken from MitcheWs Chemistry. ]
General Index.
357
GENERAL INDEX.
PAGE,
Acids 38
Acid Acetic 279
Arsenic 197
Arsenous 199
Benzoic 311
Boric 96
Butyric 273
Butylactic 292
Carbonic 93
Carbolic 307
Chromic 212
Cinnamic 326
Camphoric 323-336
Citric 296
Eugenic 324
Formic 275
Gallic 313
Glacial Acetic 279
Glyceric 298
Glycollic 291
Hydrochloric 55
Lactic 292
Malic 295
Maloric 292
Margaric 297
Metaphosphoric 83
Molybdic. 208
Nitric 67
Nitro-hydrochloric 69
Oleic 297
Oxalic 291-292-294
Oxids 46
Palmitic 297
Phosphoric 82
Permachoric 194
Phosphorous 82
Pyrophosphoric 82
Pyrotartaric 292
Salicylic 312
Selenic 79
PAGE.
Acid, Silicic 100
Stearic 297
Succinic 292
Sulfuric 75
Sulf urous.. 74
Tannic 314
Tartaric 295
Tungstic 209
Valerolactic 292
Absinthol 336
Acetic Acid 279
Acetates 280
Acids 38
Halogen 63
Acetone 261
Acetylene 304
Acetanilid 317
Aconitin.. 350
Alcohols 259-273
Aldehyds 261-274
Allyl 300
Alkaloids 341
Alum 177-180
Aluminum 175
Acetate 181
Chlorid 175-181
Hydrate 176
Oxid 178
Phosphate 179
Sulfate 177
Amalgams 155
Amids. 262
Ammonia 65
Ammonium 142
Aurate 219
Benzoate 312
Chlorid 66
Nitrate 71
Amids 261
Amins 262
358
General Index,
PAGE.
Amidogen 258
Amylene 291-302
Amyl Acetate 289
Amyl Alcohol 289
Amyl Nitrate 289
Analysis 30
Ansesthetics 71
Anisol 308
Anilin 316
Antimony 202
Acids 203
Oxids 203
Oxysulfid 204
Antimonous chlorid 2Q4
Antipyrin 317
Antiseptics 248
Aqua Regia 217
Argentum 149
Aristol 330
Arsenic 197
Arsenic Acids 199
Oxids 198
Sulfids 199
Artiads 109
Asoprol 356
Atmosphere 4
Atoms 28
Atropin 351
Attraction. 29
Auric chlorid 218
Oxid 219
Arum 214
Aurous chlorid 218
Oxid 219
Babbit's Metal ... 203
Bacilli 249
Bacteria 249
Baking Powder 295
Barium. .147
Nitrate 147
Oxids 147
Sulfate 147
Barometer 5
Basalt 175
Bases 38
Beeswax 288
Belladonna 351
PAG*.
Benzene 306
Group 311
Benzoic Acid — 311
Benzol Hydrate, 312
Beryllium 167
Benzyl Alcohol 311
Bismuth 205
Chlorid 206
Hydrate 206
Nitrate 206
Oxid 206
Oxychiorid 206
Subnitrate 206
Sulfate 206
Bleaching — 54
Blow-pipe flame 91
Borax 97-140-141
Borneol 336
Boric Acid 96
Boron 96
Britannia Metal 203
Bromin 61
Bromoform 271
Butane 267
Butter Antimony 204
Butylactic Acid 292
Cadmium 166
Caflfein 341
Calcium. 143
Benzoate 312
Carbonate 144-147
Chlorid 143
Fluorid 146
Hydrate 143
Lactate 293
Oxid 143
Phosfate 145-147
Sulfate 145
Calendula 339
Calisaya 342
Camphors 323-335
Campho-Phenic 338
Camphoric Acid 323-336
Cannabis Indica 353
Carbolic Acid 307
Carbon • 85
Compounds 252
General Index.
359
PAGE.
Carbonic Acid 93
Carbon Oxids 92-94
Disulfid 95
Carbo-IIyd rates 318
Carbom id 265
Carboxyl 260
Caryophillin 264
Capsicum 338
Caoutchouc 333
Carvacrol 329
Carvol 329
Celluloid 319
Cellulose 319
Cerium 148
Oxalate 148
Charcoal 86
Chalk 143
Chemical Affinity 29
Equations 33
Philosophy.. 103
Chemism 29
Chili Saltpeter 134
Chloral 281
Camphor.. 338
Hydrate 281
Chlorin... 53
Chlorinated Lime 46
Chloroform 268
Chloroplatinates 223
Chromium 210
Compounds 210
Cinnabar; 144
Cinnamic Acid. 326
Citric Acid 296
Cinchona 342
Clay 375-379
Cobalt 195
Compounds 195
Cohesion 29
Colloids 101
Combustion. 87
Copper 152
Compounds 153
Amalgam 155
Cocain 346
Collodion 320
Cologne 322
Corundum 175
PAGE.
Creasote 309
Creasol 310
Cresylol 310
Cream Tartar 295
Cyanogen 258
Cymene 328
Decay 245
Black 77
Brown 60
Dental 57
White 69
Dentists' Gold Foil 216
Destructive Distillation 245
Dextrin 318
Diamond 85
Disinfectants 248
Disinfection 249
Distillation 17
Dolomite 164
Dry Method 217
Dynamite 299
Earths 147
Ebonite 333
Ebullition 16
Electrolysis 224
Elements 25
Electro-negative 227
" positive 227
Electro-plating 229
EfFects of Medicines 127
Emory 175
Esters 260
Essential Oils 264-325
Equivalency 107
Variations 112
Ethane 253-267
Ethene 88-253
Alcohol 291
Erbium 148
Eremacausis 246
Ether 284
Ethers 284
Compound 280
Haloid 269
Mixed 250
Oxygen . . 259-284
860
General Index.
PAGE.
Ethine 304
Erythroxylon 346
Ethyl 277
Alcohol 277
Chlorid 286
Oxid 284
Lactates 293
Ethylene 305
Eucalyptol 328
Eugenol 324
Euphorin 354
Europhen 350
Evaporation 15
Face Powder 206
Faradic Current 231
Fatty Acids 279
Felspar 175-179
Fermentation 246
Ferric Chlorid 186
Hydrate 186
Oxid 186
Sulfate 186
Ferrous Carbonate 185
Chlorid 185
Chromite 212
lodid 185
Oxid 185
Salts 185
Sulfate 185
Sulfid. 185
Flame 89
Blow-pipe, . . ,. 95
Fluorin.. 62
Fowler's Solution 202
Fulminating Gold. 219
Fusible Alloys 205
Gallic Acid.. 313
Gallium 281
Galvanism 224
Gases 28
Gaseous Diffusion 5
Germicides 248
Glacial Acetic Acid 279
Glass. 99
Glucinum 157
Glucose 318-320
PAGE.
Glucosids.. 316
Glycerin 298
Glycerita 300
Glycolls 291
Gold ... 214
Alloys 215
Facings 220
Precipitates ^ 217
Granite . . 175
Grape Sugar 320
Graphic Formulae 110
Graphite 86
Gravitation 29.
Gums 319
Gun-cotton 319
Powder 134
Gutta-percha 333
Haemostatic 188
Halogens : 58
Hamamelis 354
Hasheesh 353
Heat 6
Atomic 104
Combustion of 91
Conduction 10
Effects 7
Expansion 7
Latent 13
Nature of 18
Radiant 22
Specific. 12
Units 50
Hemetite 183
Homologous Series 254
Hoffmann's Anodyne 285
Table 253
Hops 339
Horn Silver 149
Hydrogen 49
Chlorid 55
Permanganate 194
Peroxid 51
Hydro-Naphthal 334
Hydro-Carbons 253
Hydraulic Cement 175
Hyoscymin 353
General Index.
361
PAGE.
Illuminating Cas 87
Imidogeu 258
Iiidium.. . . . . 181
India Rubber 333
Ink 188
lodin 60
Iodoform 270
Iridium .-. 223
Iron 183
By Hydrogen 187
Iron, Cast 184
Dyalized 187
Malleable 184
Pig 184
Wrought 184
Isobu tane 267
Isomerism 263
Optical 264
Isomorphous 105
Isopentene 302
Isologous Series 254
Kaolin 179
Ketones 261-274
Labaraques Solution 140
Lactic Acid 292
Latin Abbreviations 121
Law, Avagrado 109
Even Numbers ... Ill
Periodic 233
Leucomains 341
Lead 168
Lead Acetates 169-280
Carbonate 169
Oxids 169
Light 18
Decomposition 20
lieflection 21
Refraction 19
Lime 143
Water 144
Linimentum Calcis 146
Liquids 28
Litharge 169
Lunar Caustic 149
Magnatite 183-187
31
# PAGE.
Magnesium 164
Compounds 165-166
Malic Acid 295
Malouic Acid 292
Manganese 194
Compounds 194
Margaric Acid ,. 297
Margarin 298
Marsh's Test 198
Marsh Gas 87
Masses 28
Matter, Constitution of 25
Compound 25
Elementary. 25
Materia Medica 120
Mercury 154
Compounds 156-157
Meerschaum 164
Meta-Compounds 173
Metallic Alloys 128
Classification 130
Elements 128
Properties 130
Methane 87-252-267
Methene 253
Methenyl 268
Methyl 257
Alcohol 273
Menthol 332
Metric System 123
Mica 175
Micro-Organisms 246
Mixed Ethers 259-288
Molecular Weights 105
Molecules 28-105
Compound 30
Simple 30
Molybdenum 208
Compounds 208
Monatomic Alcohols 273
Morphin , 345
Mosaic Gold 174
Monsel's Powder 187
Solution 187
Myrrh 335
Naphthalin 317-334
Nebulae 242
362
General Index,
PAGE.
Nickel 195
Compounds 196
Nicotin ... 341
Niobium 207
Nitrogeu.-. — 64
Oxids 67
Nitric Acid 67
Nitrous Ether 285
Oxid 71
Nitro-Benzene 316
Glycerin 299
Cellulose 319
Nitryl 258
Nomenclature 33
Notation 31
Nutgalls 314
Oil, Caraway 328
Cassia 325
Cinnamon 325
Cloves 324
Eucalyptus 327
Orange Flowers. 333
Peppermint 332
Sassafras 325
Turpentine 323
Wintergreen B27
Oils, Essential 264-325
Olefins 290
Oleic Acid 297
Olein 298
Opium 345
Optical Isomerism 264
Organic Acids 260
Chemistry 244
Ortho-Compounds 172
Osmium 223
Oxalic Acid 291-294
Oxidation 44
Oxids, Acid 46
Basic 46
Neutral 46
Oxygen. 43
Ethers 259-284
Ozone 46
Test 48
Palladium 223
PAGE.
Palmitic Acid ... 297
Paraflns 266
Paris Green 199
Pental ■■ 302
Perissads 109
Periodic Law 233
Table 236
Phenol 308
Phenols 332
Phenol Sodique 309
Phenacetin 317
Phenetol 308
Phenic Acid 307
Phenyl 307
Amin 316
Alcohol 307
Phosphorus 81
Compounds 82
Phosphin 83
Platinum.. .. 221
Backing 220
Compounds 222
Plumbum Acetate 169
Chromate 212
Polymerism 264
Porcelain 99-179
Teeth 180
Potassium 131
Compounds 132-137
Chromate 212
Cyanid 258
Aurate 219
Prepared Chalk 147
Primary Alcohols 273
Proof Spirit 278
Proponyl 298
Alcohol 298
Ptomains 247-341
Purple of Cassias 172-219
Propane 267
Putrefaction 245
Putty Powder 172
Pyridin 317
Pyoktanin 344
Pyrethrum 333
Pyroxylin 319
Quinin... 342
General Index.
363
PAGE.
Quinicin 317
Quick-silver 154
Radicals 114
Compound 116
Red Lead 169
Resins 223-335
Resorcin 332
Rhodium 223
Robinson's Remedy 309
Rosin 323
Ruby 175
Rules, Prescribing.. 122
Ruthenium 223
Salts 38
Salol 317
Salicylic Acid 312
Saltpeter 131-136
Samarium 148
Scandium 182
Selenium 79
Silicon 98
Silicic Acid 100
Silicon Oxid 98
Siderite 183
Silver 148
Compounds 149-150
Slate 175
Soap 298
Secondary Alcohols 273
Solar Spectrum 37
Solids 28
Sodaj Chloratse 140
Sodium 138
Arsenite 199
Compounds 138-141
Bismuthate 207
Lactate 293
Tungstatc 209
Specific Gravity 1
Heat 101
Spectrum Analysis 238
Spermaceta 288
Spores 249
Starch 318
Stearin 298
Stereo-Chemistry 263
PAGE.
Stramonium 353
Stibin 183
Strontium 14/,
Nitrate 147
Storage Batteries, 230
Sugars 320
Sucrose 320
Sublimation 17
Sulfur.. 73
Compounds 74-78
Tannic Acid 314.
Tantalum 207
Tartar 144
Tartaric Acid 295
Tartar Emetic 204
Teeth, Analysis 356
Tertiary Alcohols 273
Terpenes 322
Tellurium 80
Thallium 170
Thermometers 8
Thorium 174
Thymol 329
Tin 170
Compounds 172
Titanium 174
Toluene 306
Trinitophenol — 320
Tungsten 208
Compounds 208
Type Metal 203
Uranates 211
Uranium 209
Compounds 209
Yellow 210
Uranyl 209
Valerolactic Acid. 292
Vanadium 207
Oxids 207
Vapor Density 106
Verdigris 280
Vermilion.. 157
" Vitalized Air " 286
Volatile Oils 323
364
General Index.
PAGE.
Water 50
Glass. 90
Weights, Measures 123
Wet Method 216
White Lead 169
Witch-Hazel..... 354
Wolfram 208
Yttrium 148
PAGE,
Zinc 160
Cblorid 161
Oxid 161
Oxychlorid 162
Oxy-phosphate 162
Sulfate 163
Zirconium 174
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