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ELEMENTS OF CHEMISTRY 
 
 AND 
 
 DENTAL MATERIA MEDICA 
 
 y by 
 
 J. S. CASSIDY, D.D.S., M.D 
 
 Professor of Chemistry and Materia Medica in Ohio College of 
 Dental Surgery 
 
 m^' 
 
 CINCINNATI 
 ROBERT CLARKE & CO 
 
 1893 
 
^1> 
 
 Copyright, 1892, 
 By JAMES S. CASSIDY 
 
TO 
 
 ELIZA GUYTON", 
 
 IN LOVING APPRECIATION OF HER 
 
 CHRISTIAN FORTITUDE 
 
 AND 
 
 EXCEEDING PATIENCE 
 
 UNDER MANY TRYING CIRCUMSTANCES, 
 
 (lijis Book is Slfodiottafrlg ^nstribcb, 
 
 BY HER HUSBAND, 
 
 THE AUTHOR. 
 
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, and the approximate re- 
 
 (v) 
 
vi Preface. 
 
 lations between the Metric, and Apothecaries sys- 
 tems, of weights and measures, will not, I trust, 
 be 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, has 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, Eoscoe's, 
 Crooke's, and Barker's Chemistry; Miller's Mi- 
 crobes, and Biddle's, Potter's, Gorgas' Dental, Bar- 
 
Preface. vii 
 
 tholow's, Farquharson's, and Waring's Materia 
 Medica. To them, 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 Chlorm," Iodin, Glycerin, 
 Cocam, Oxid, Sulfur, 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. 
 
INORGANIC CHEMISTRY 
 
 PART 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 weight; 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 weight 
 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- 
 
 (l) 
 
2 Inorganic Chemistry. 
 
 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 ascertained 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 equilibrium of floating bodies is afforded 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, being 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 
 liquid will be 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 density, when ap- 
 plied to a gas, implies that hydrogen 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. 
 
 Gases 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 poiver 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 will pass 
 to the H side. The densities of these two gases 
 are as 1 to 16 ; their relative rates of diffusion, 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 C0 2 , which is freely soluble in 
 water, escapes easily thus dissolved, through the 
 wet membranes of the lunsrs. 
 
Effects of Heat, 
 
 CHAPTER II. 
 
 EFFECTS OE HEAT. 
 
 One of the most general effects 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 with 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, (39°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. 
 
 TV. The actual amount of expansion is equal to 
 -g-g-j-ff- 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. In 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 filling. 
 
 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. 
 
 CHAPTER III. 
 
 SPECIFIC HEAT. 
 
 Equal weights of different substances require 
 different amounts of heat to raise them 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. Now, 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. <?., 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 the spe- 
 cific heats — capacities for heat — of the various 
 
Specific Heat. 13 
 
 substances. The specific heat of water is greater 
 than 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 lb. 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. 
 
 absorb 
 liquid. 
 
 absorbed in the change of state from solid to 
 
 1 lb. of water at 70°C. \ _ 7AO p 
 1 lb. of ice at 0°C. / ~ /u u 
 
 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 100°C. mixed with a pound 
 of water 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- 
 ritic 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 other 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°C., (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 
 tilled 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 
 be 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 depositiou 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 
 2 
 
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- 
 tion, will he bent from a continuous straight line ; 
 in short, refracted. The rule of simple refraction 
 of light is stated thus : when a ray of light passes 
 from a rare through a denser medium it is bent toward 
 a line drawn 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 
 
 1 
 
 A 
 
 / / 
 B/ / 
 
 
 /C 
 
 
 If the incident ray of light, I, fall upon the plate 
 glass, J., at the angle shown, then instead of .pass- 
 ing straight through the glass to JB, 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 J?, the light is refracted; and if throVn on a 
 white screen C, 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 
 
Distillation. 21 
 
 mathematical perception. The red color is dis- 
 tinguished 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 j 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, I, 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. 
 
 Almost all things upon the general surface of 
 the earth, incline toward each other at promiscu- 
 ous angles, and so reflect the light diffused. It is 
 by means of this diffused reflected light 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. 23 
 
 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 fact, 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 tbe 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 remain 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. 
 
 Hectors are poor absorbers of heat, and vice versa. 
 The power -of absorbing and of radiating heat, is 
 in direct proportion. The surface which absorbs 
 heat most perfectly, will when heated, also radiate 
 most perfectly. If two vessels of equal size and 
 material, one having a polished white 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 with 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. 25 
 
 CHAPTER V. 
 
 CONSTITUTION OF MATTER 
 
 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 
 
 Columbium 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 
 
 Lithium 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 
 
 Rubidium 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 
 
 Ziuc Zrt 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 
 aud nitrous oxide, of gases. 
 
 Each of these physical conditions is sub-divided 
 into masses, 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 be 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 2 0, or marble CaC0 3 . 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 of 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 2 0, on the 
 contrary, is a compound, because by analysis it 
 gives up two different 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 VI. 
 
 CHEMICAL NOTATION AND NOMENCLATIVE. 
 
 The letters, symbols — H, 0, or 1ST, 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, HC1 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, H 2 0. 
 The formula of peroxide of hydrogen, which con- 
 tains two atoms of hydrogen and two atoms of 
 oxygen is written H 2 2 . 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 2H 2 0, 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(NH 4 C1) or (NH 4 C1) 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 formula?. 
 
 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 formula? 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 
 
 2HC1 + Na 2 C0 3 
 
 = 2NaCl + H 2 + 
 
 co 2 
 
 Hydrogen Sodium 
 
 Sodium Hydrogen 
 
 Carbon 
 
 Chloride. Carbonate. 
 
 Chloride. Monoxide. 
 
 Dioxide, 
 
 The above equation is also an illustration of 
 what 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, (H 2 0.) The 2 atoms of chlorine set 
 free, unite with the 2 atoms of Na forming 2 mole- 
 cules of common salt, (2 ^aCl,) and the remaining 
 group, C0 2 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 : 
 
 E"H 4 N0 3 + Heat = 2H 2 + N 2 
 
 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 chloride, 
 
34 Inorganic Chemistry. 
 
 meaning, evidently, a combination of H and 01, 
 (HC1;) hydrogen monoxide, of H and 0, (H 2 0;) 
 sodium chloride, of ~N& and CI, (NaCI ;) nitrous 
 oxide, of N and 0, (K 2 0.) 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 "N, thus, 
 NH 4 N0 3 , because we can better realize the relation 
 that really exists between the two radicals NH 4 
 and N0 3 , which form the molecule in question. 
 
 By referring to the few preceding formulas we 
 preceive the rule is observed, H is electro-positive 
 to CI; Na to C andO; Ha to 01; H to ; 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 tbe 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 1 C1 35-5 ; 
 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 more than one 
 proportion, the distinctions are made by employ- 
 ing the Greek numerals, mon, di, tri, etc., to indi- 
 cate the number of atoms or radicles in the mole- 
 cule. H and form two compounds, H 2 and 
 H 2 2 ; the first formula may be called hydrogen 
 monoxide, the second hydrogen dioxide, signifying 
 one atom of oxygen and two atoms of oxygen re- 
 spectively. The binary compounds of 1ST and O 
 •furnish perhaps the best example of these dis- 
 tinctions : 
 
 N 2 
 
 N 2 2 
 
 N 2 3 
 
 N 2 4 
 
 N 2 5 
 
 Nitrogen 
 
 Nitrogen 
 
 Nitrogen 
 
 Nitrogen 
 
 Nitrogen 
 
 Monoxide. 
 
 Dioxide. 
 
 Trioxide. 
 
 Tetroxide. 
 
 Pentoxide. 
 
 The name alone, therefore, indicates the number of 
 atoms in each molecule ; and they are all equally 
 ^'nitrogen 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 nitrous oxide, and the highest, or 
 pent (five) oxide is known as nitric oxide. The 
 prefix hyper (reduced sometimes to per) meaning 
 above, is found convenient to apply to the name of 
 
36 Inorganic Chemistry. 
 
 a compound containing more of the negative ele- 
 ment than exists in a previously named compound 
 of the same elements. Thus nitrogen dioxide 
 might be named as hypemitrous oxide. The prefix 
 hypo, meaning under, might, on the same principle, 
 be applied to nitrogen tetroxide, and the latter 
 named hypomtrie oxide. These rules apply to any 
 series of compounds made up of the same two 
 elements. 
 
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 he understood that all acids contain H. 
 Nitric acid, as its name implies, contains E\ If 
 there be at least three elements in the molecules of 
 acids, a fact which usually obtains, we are safe in 
 assuming that is the other element, unless the 
 name of the acid is otherwise distinguished. We 
 have, therefore, in the above acid, H and N 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 nitric acid is thus ascertained to be HX0 3 . 
 
 Then, there is another oxy-acid of nitrogen ; it 
 is named nitrons acid — HX0 2 — because it contains 
 less negative than nitro'c acid. 
 
 The names of the other acids are derived in the 
 same way. Sulphunc acid, is formulated H 2 S0 4 ; 
 sulphurous acid, H 2 S0 3 ; chlonc acid, HC10 3 ; 
 
38 Inorganic Chemistry. 
 
 chlorous acid, HC10 2 ; and hypo-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 : 
 
 NaO + H£T0 3 = 
 
 = H 2 + NatfOj 
 
 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 thus, is sodium nitrate. All 
 
Notation and Nomenclature. 39 
 
 salts of nitric acid are nitrates. Salts of nitro?/s 
 acid are named nitrites. In the same way, all salts 
 produced by the union of sulphuric acid with abase 
 are named sulphates. Sulphuroas acid produces 
 salts called sulphites, etc. The names of all salts 
 whose acids contain more than two elements to the 
 molecule, such as H^0 3 , terminate in either ate or 
 ite; while the names of salts derived from acids 
 whose molecules contain only two elements, end in 
 ide. For instance, hydrochloric acid — HC1 — bi- 
 nary, because made up of only two elements, acting 
 on the basic metal sodium, !Na, produces a binary 
 salt whose name should end in ide, as will be seen 
 by the following reaction : 
 
 ISTa + HC1 = H + ^aCl 
 
 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 : 
 
 Zn + H 2 S0 4 = ZnS0 4 -f 2H 
 
 Zinc. Sulphuric Zinc. Hydrogen. 
 
 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 of the base to form water. 
 
 ZnO + H 2 S0 4 = ZnS0 4 + H 2 
 
 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. Not 
 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 II, and one atom of 0,=H 2 0; 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 they do ndt blend 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, C0 2 , differ only by one atom of 0, 
 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 (HgCl 2 ), 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 (Hg 2 Cl 2 ) is not soluble in water; it is a 
 comparatively mild medicine, one hundred centi- 
 grams (15 grains) might be taken without danger. 
 4 
 
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 a3 one at least, of the former, is 
 a necessary constituent of all chemical compounds. 
 Their introduction, 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, 16. 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. 
 KC10 3 + Heat = KC1 + 30 
 
 Potassium Potassium Oxygen, 
 
 Chlorate. Chloride. 
 
44 Inorganic Chemistry. 
 
 All the 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 (Mn0 2 ), 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., H 2 0, CaO, Au 2 3 , etc.). 
 
 When a single 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 sufficiently 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 two 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 so 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 + S0 3 = BaS0 4 
 
 Barium Sulphuric Barium 
 
 Oxide. Oxide. Sulphate. 
 
 The acid oxides unite with water to form acids, 
 
 as: 
 
 S0 3 + H 2 = H 2 S0 4 
 
 Sulphuric Water. Sulphuric 
 
 Oxide. Acid. 
 
 Basic oxides react with acids to form correspond- 
 ing salts, as : 
 
 CaO + H 2 S0 4 = CaS0 4 + H 2 
 
 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 + H 2 = Ca(HO) 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 (H 2 S0 4 ). 
 
 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 : 
 
 1st. By heat ; as when platinum wire is merely 
 heated in the air. 
 
 2nd. By light; as when C0 2 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 line, 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 
 fourteen aud 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 nebulse. 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 
 
 Zinc. 
 
 The gas may be collected over water or by dis- 
 5 
 
 2HC1 = 
 
 ZnCl 2 
 
 + 
 
 2H 
 
 Hydrochloric 
 
 Zinc 
 
 
 Hydrogen. 
 
 Acid. 
 
 Chloride. 
 
 
 
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. (932°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 
 (H 2 0), 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, 
 chemically.' 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, N 2 0, C0 2 , 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 water 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 paris. 
 
 Oxygen and hydrogen may be induced to unite 
 in the proportion of two atoms of each, to form 
 hydrogen dioxide (H 2 2 ), 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 : 
 
 Ba0 2 
 
 + 
 
 H 2 CO S = 
 
 = BaC0 3 
 
 + 
 
 H 2 2 
 
 Barium 
 
 
 Carbonic 
 
 Barium 
 
 
 Hydrogen 
 
 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 own volume of free oxygen: The tem- 
 perature of summer heat will cause the molecule 
 (H 2 2 ) 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, 01. At. wt. 35.5. Sp. gr. 2.46. 
 
 Chlorine was discovered by Scheele, in 1774. Its 
 elementary character was proven by Davy, in 1810, 
 who gave it the name it bears, which 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 : 
 Mn0 2 - 
 
 Manganese 
 Dioxide. 
 
 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. 
 
 4HC1 =z 
 
 2H 2 
 
 + 
 
 MnCl 2 
 
 + 2C1 2 
 
 Hydrochloric 
 Acid. 
 
 Water 
 
 
 Manganese 
 Chloride. 
 
 » Chlorine 
 
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 chlori, 
 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 : 
 H 2 0, 2C1 = 2HC1 + 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 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 filled with chlorine, 
 dense volumes of smoke will be evolved, owing to 
 the chlorine taking up with the H of the candle, 
 resulting in HC1, 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 fine, 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 
 noncombustible. Its specific gravity is 1.264, its 
 density (H 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 together quantities of common salt 
 (]STaCl) and strong sulphuric acid, as indicated by 
 the following equation : 
 
 2NaCl + H 2 S0 4 
 
 = Na 2 S0 4 + 2HC1 
 
 Sodium Sulphuric 
 
 Sodium Hydrochloric 
 
 Chloride. Acid. 
 
 Sulphate. Acid. 
 
 The gas (HC1) is very soluble in water. A given 
 volume of water 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 water, 
 however, is not expressed in the reactions of the 
 acid, so that the formula HC1 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, with 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 + FeCl 2 
 
 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 HC1. 
 
 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 affinities 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. 
 
 CaC0 3 
 
 + 
 
 2HC1 = 
 
 CaCl 2 + H 2 
 
 + 
 
 co 2 
 
 Calcium 
 
 
 Hydrogen 
 
 Calcium 
 
 
 
 Carbonate. 
 
 
 Chloride. 
 
 Chloride. 
 
 
 
58 Inorganic Chemistry. 
 
 The calcium phosphate of the tooth, although 
 not 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 HC1 : 
 HC10 4 , Perchloric acid. 
 HCIO3, Chloric acid. 
 HC10 2 , 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, C1 2 0, C1 2 2 , C1 2 4 , 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 XL 
 
 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 
 
 BEOMINE. 
 
 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 — CaF 2 — 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. 
 
 CaF 2 + " H 2 S0 4 = CaSo 4 + 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 .. HC1 
 
 Hy driodic acid HI 
 
 Hydrobromic aci d HBr 
 
 Hydrofluoric acid HF 
 
Halogen. 63 
 
 The first and last of these acids have already 
 been sufficiently described. The second (HI) and 
 third (IIBr) are also pungent, colorless gases, very 
 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 HI0 3 and HBr0 3 , 
 corresponding to chloric acid HC10 3 . Their salts 
 are called iodates and bromates. 
 
64 Inorganic Chemistry. 
 
 CHAPTER XII. 
 NITROGEN. 
 
 Symbol, N. 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-fifths 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. 65 
 
 Besides its existence in the atmosphere, it is found 
 in 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 (NH 3 ). 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). 
 
 (NH 4 C1) S 
 
 + 
 
 CaO = 
 
 CaCl 2 
 
 H 2 
 
 + 2NH 3 
 
 Am. chloride. 
 
 
 Calcium 
 Oxide. 
 
 Calcium 
 Chloride. 
 
 Water. 
 
 Ammonia. 
 
 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 heating, 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 (OTI 4 ), which 
 has received the name of ammoirmm, because it 
 acts in many cases like an atom of some of the 
 metals. Thus: 
 
 NH 3 + HC1 = (NH 4 )C1, 
 
 Ammonia. Hydrochloric Ammonium 
 
 Acid. Chloride. 
 
 analogous to sodium chloride, !N"aCl. 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 Amnion — in honor of Jupiter 
 Amnion, whom they worshiped, and from which 
 the name ammonia is derived. Ammonium iodide 
 and ammonium bromide are analogous salts. 
 
 Nitrogen and oxygen unite with each other in Hive 
 proportions. Their compounds have the following 
 names and formulas : 
 
 Nitrogen pentoxide (or nitn'c oxide) ^2^5 
 
 Nitrogen tetroxide ^2^4 
 
 Nitrogen trioxide ^2 O 3 
 
 Nitrogen dioxide ^2^2 
 
 Nitrogen monoxide (or nitrows oxide).... N 2 
 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: 
 2AgN0 3 + 2C1 = 2AgCl + + N 2 5 
 
 Argeutum 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 : 
 N 2 5 + H 2 = 2HNO3 
 
 Nitric oxide. A'ater. 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 : 
 
 NH 3 + 4 = H 2 + HN0 3 
 
 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 : 
 
 KN"0 8 + H 2 S0 4 = HKS0 4 + HKO3 
 
 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 
 
 Nitrogenous 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 
 
 luVyI 3' 
 
 9HC1 
 
 + 3HN0 3 = 
 
 : 6IL 
 
 >o 
 
 + 
 
 3NOC1 
 
 + 
 
 2C1 3 . 
 
 2Au 
 
 + 2C1 3 =x 2Au 
 
 IC1 3 / 
 
 
 
 
 
 
 The NOC1 is of no importance, some authorities 
 claiming that the residue of nitrogen and oxygen 
 remain together as 3NO, 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 decidedly 
 alkaline. The favorite trysting place of the fer- 
 ments, in dental caries, is usually a quiet nook, 
 unfrequented by the brush, where 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 (N 2 2 ) is able 
 to take up oxygen from the air and is thereby con- 
 verted into the tetroxide, N 2 ^4 ; the latter sub- 
 stance is a good oxidizing agent, as we shall learn 
 by and by. The trioxide (N 2 3 ) is the anhydrous 
 oxide of nitrous acid, as the pentoxide (N 2 5 ) is of 
 nitric 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, N 2 0. 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, an 
 American dentist, of Hartford, Conn., employed it 
 as an anaesthetic, and in so doing, became the orig- 
 inal, genuine discover of anaesthesia. 
 
 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 : 
 
 NH 4 N0 3 + Heat = 2H 2 + N 2 
 
 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 15° (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 
 sw T eet, and remains so indefinitely, after dissolving 
 even a small quantity of the gas. 
 
 Nitrous oxide is readily 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 (C0 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 chernico-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. 
 
 Sulphur (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 sulphur, 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 S0 2 ; 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 (S0 2 ) 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: 
 
 S0 2 + H 2 = H 2 S0 3 
 
 Sulphurous acid. 
 
 The salts of this acid are named sulphites. 
 
 The other oxide of sulphur is the trioxide (SO 3 ) 
 
Sulphur. 75 
 
 or sulphuric oxide. It is usually prepared by oxi- 
 dizing sulphurous oxide — the dioxide S0 2 . Sul- 
 phur trioxide is a white wax-like solid, of a silky, 
 fibrous appearance, somewhat resembling asbestus. 
 It unites with water, giving rise to great heat, pro- 
 ducing sulphuric acid: 
 
 S0 3 + H 2 = H 2 S0 4 
 
 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 S0 2 . 
 
 2d. The presence of nitric acid (2ELN"0 3 ) which 
 supplies nitrogen tetroxide N 2 4 . 
 
 3d. The latter compound gives oxygen to the 
 S0 2 , changing it into S0 3 , and is itself reduced to 
 nitrogen dioxide N 2 2 . 
 
 4th. Water, heated by the burning sulphur, 
 unites with the S0 3 , producing sulphuric acid. 
 
 5th. The taking up of oxygen from the air by 
 
76 Inorganic Chemistry. 
 
 the nitrogen 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 -f 20 = S0 2 . 
 
 2S0 2 + N 2 4 = 2S0 3 + £T 2 2 . 
 
 S0 3 + H 2 = H 2 S0 4 . 
 
 N 2 2 + 20 = N 2 4 . 
 
 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- 
 cific gravity about 1.85. Freezes at — 26° (— 15°F.) 
 and boils at 328° (622°F.). It has a strong affinity 
 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 (H 2 S), 
 these being evolved from the organized debris in 
 contact with the tooth, and 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 
 (CaS0 4 ), 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 further inroads both 
 of the causing agent and other solvents. 
 
 A gaseous compound of sulphur and hydrogen 
 (sulphuretted hydrogen, dihydrogen sulphide, sul- 
 phydric acid, etc., H 2 S), 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 sulphur, 
 and in the selenides of silver, mercury, lead, and 
 copper. It unites with hydrogen to form a gaseous 
 compound (H 2 Se), analogous to sulphuretted hy- 
 drogen, of an extremely nauseous odor, It forms 
 acids corresponding to those of sulphur: selenious 
 acid (H 2 Se0 3 ), and selenic acid (H 2 Se0 4 ), 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 (H 2 Te), and with oxygen (Te0 2 Te 
 3 ), and corresponding acids (H 2 Te0 3 , II 2 Te0 4 ). 
 
80 Inorganic Chemistry. 
 
 CHAPTER XIV. 
 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 
 "S 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 afflicted 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 fire until, heated to 260° 
 (500°F.). 
 
 There are two oxides of phosphorus : that pro- 
 duced by oxidation, phosphorous oxide (P 2 3 ), 
 and that produced when phosphorus is burned in 
 the air or in oxygen, phosphoric oxide (P 2 5 ). 
 Phosphoric oxide, united with water, forms phos- 
 phoric acid : 
 
 P 2 6 + 3H 2 = 2H 3 P0 4 
 
 There are several kinds of phosphorus acids, 
 but two or three only need be mentioned. 
 
 Ordinary phosphoric acid (H 3 P0 4 ), 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 filling, or for strength- 
 ening frail walls in cavities of teeth. 
 
 As phosphoric acid is formulated from 3 mole- 
 cules of water, ^rophosphoric acid is formulated 
 from 2 molecules, and metaphosphoric acid from 1 
 molecule of water, thus : 
 
 P 2 5 + 3H 2 = 2H 3 P0 4 , phosphoric acid; 
 
82 Inorganic Chemistry. 
 
 P 2 5 -f- 2H 2 = H 4 P 2 7 , pyrophosphoric 
 acid; 
 
 P 2 5 4- H 2 = 2HP0 3 , 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 ortho 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 (PH 3 ), correspond- 
 ing with ammonia (N"H 3 ), 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 + 3H 2 + 3KHO = 3KPH 2 2 -}- PH 3 
 
 Pot. Hydrate. Pot. Hypophosphite. 
 
 The PH 3 is adulterated with traces of P 2 H 4 , 
 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 (P 2 5 ). 
 
 There are two chlorides of phosphorus, the tri- 
 chloride (PC1 8 ) and pentachloride (PC1 6 ). The 
 pentachloride is a solid substance, and is formed in 
 the experiment snowing 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 
 tbree distinct allot ropic forms, wbich 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-four 
 parts, by weight of the same compound (C0 2 ). 
 
 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 elect roty ping, 
 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. Noxious 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 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 + H 2 + 30 = * H 2 + C0 2 
 
 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 
 hydrogen, methane, ethene, ethine, and traces of 
 CO, C0 2 , N", andH 2 S. 
 
 Methane, marsh gas, or light carburetted hydro- 
 
88 Inorganic Chemistry. 
 
 gen, CH 4 , 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, u 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. 
 
 ]S"aC 2 H 3 2 + E"aHO = Na 2 C0 3 + CH 4 
 
 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 
 (C 2 H 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 : 
 
 C 2 H 6 - H 2 = C 2 H 4 
 
 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 (C 2 H 3 C1) 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 4 and C 2 H 4 , 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, (H 2 0), and carbonic acid gas, or carbon- 
 dioxide (C0 2 ). 
 
 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 atmospheric oxygen. 
 
 A flame, 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 off by the less dense hydrocarbons, owing to 
 the difference, in affinity, between the carbon and 
 hydrogen of the burning gases, and oxygen. 
 
 Burning gases, containing relatively much hy- 
 drogen, give off 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 therefore 
 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 
 heating power. 
 
 The same principles apply to the mouth blow- 
 pipe flame. Air (oxygen), is blown by the cheeks, 
 into the interior of the flame, w T hich 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 
 (C0 2 ). 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 of 
 ordinary combustion, and fermentation, and putri- 
 cation of vegetable and animal tissues. From the 
 bodies of living animals it is exhaled by means of 
 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 water, by reaction between a 
 carbonate and a dilute acid, usually hydrochloric 
 or sulphuric, as the following equation will show : 
 
 Ca CO 3 
 
 + 
 
 H,S0 4 = 
 
 = CaS0 4 
 
 + H 2 + CO, 
 
 Calcium 
 
 
 Sulphuric 
 
 Calcium 
 
 Water. Carbon 
 
 Carbonate. 
 
 
 Acid. 
 
 Sulphate. 
 
 Dioxide. 
 
 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 C0 2 can he 
 confined in water under pressure, as is seen in 
 soda water, certain mineral waters, sparkling 
 winesj and beer, which, on exposure to the air, 
 rapidly lose their excess of C0 2 , 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 water, 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. 
 
 H 2 -+- C0 2 = H 2 C0 3 
 
 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. 
 
 H 2 C0 3 = H 2 + C0 2 
 
 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. 
 
 CaC0 3 + Heat = CaO + C0 2 
 
 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 (C0 2 -(- C = 2CO), 
 at which point the resulting CO, meeting with at- 
 mospheric oxygen, unites with the latter, burning 
 with a blue flame, and producingC0 2 . C04-0=C0 2 . 
 
 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 (CS 2 ) 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 
 mixed with air is explosive, and the compound 
 itself is very combustible, yielding carbon dioxide 
 and sulphur dioxide, CS 2 + 60 = C0 2 -f- 2S0 2 . 
 
 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 (CN), to be described under " Organic 
 Ceiemistry." 
 
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, B 2 3 , is formed whenever boron 
 is burned in the air or oxygen. United with 
 3 molecules of water, it forms boric (ortho-boric) 
 acid. 
 
 B 2 3 + 3H 2 = 2H.BO,. 
 
 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 gaseous com- 
 
Silicon. 97 
 
 pound, BH 3 , resembling NH 3 and PH 3 . With F 
 it forms a colorless gas, and with CI a volatile 
 liquid ; but by far the most important compound 
 of boron is borax (Na 2 (B 2 3 ) 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- 
 conuoride, 4K + K 2 SiF 6 = 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 erust of the 
 
 earth. 
 9 
 
98 Inorganic Chemistry. 
 
 The oxide of silicon (S0 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. 
 
 Si0 2 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. 
 
 Si0 2 + Na 2 C0 3 = IsTa 2 Si0 2 + C0 2 . 
 
 Sodium Silicate. 
 
 The silicates of sodium and potassium are known 
 as water 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 4 , analogous to CH 4 . It unites with 
 chlorine, bromine, and iodine, SiCl 4 , SiBr 4 , Sil 4 , 
 corresponding to carhon chloride, bromide, and io- 
 dide It also forms a chloroform, SiHCl 3 , similar 
 in some respects to ordinary chloroform, CHC1 3 . 
 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 nature* 
 
 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 4 Si0 4 . By losing a 
 molecule of water it becomes meta-silicic acid, 
 H 2 Si0 3 . 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 dializer, 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 jelly. 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. 
 
PART SECOND. 
 
 INORGANIC CHEMISTRY. 
 
 CHAPTER I. 
 
 CHEMICAL PHILOSOPHY— Resumed. 
 
 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, H 2 0, 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 S0 3 is 80; these two substances 
 combine with each other in the above proportions 
 to form a molecule of H 2 S0 4 , whose weight is the 
 sum of 18 + 80 = 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 
 degree. 
 
 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, Fe 2 3 , 
 is isomorphous with sesquioxide of aluminum, 
 A1 2 3 ; 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, HH ; the molecular weight of 
 
104 Inorganic Chemistry. 
 
 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 weight, 
 or its molecular volume is equal to 2 atomic vol- 
 umes. Those elementary gases or* vapors whose 
 molecules are supposed to contain 2 volumes, or 2 
 atoms, have a density, referred to hydrogen 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 H — H, 0=0, 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 = 32 ; 
 
 its density is one-half of 32, or 16. Ozone, / \ 
 J 
 
 has a molecular weight of 48; its density is 24. 
 Carbon dioxide, whose formula is C0 2 , has a 
 molecular weight of 12 -f- 32, or 44; 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 
 
 h is also noticed that the gaseous product of the 
 union of two elementary gases, when combining in 
 equal volumes, retains the original volume of its 
 constituents; as 1 vol. of H and 1 vol. of CI form 
 2 vols, of HC1. 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 II and 1 vol. of form 2 vols. H 2 ; 
 
 1 vol. of ethyl CH 5 and 1 vol. of CI form 2 vols. 
 CH 5 C1; 
 
 2 vols, of ethyl (CH 5 ) 2 and 1 vol. of form 2 
 vols. (CH 5 ) 2 0. 
 
 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. 
 
 ments 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, HC1 ; they are both monads. One atom of 
 Na will displace H and take up with the CI : 
 HC1 + *Ta = NaCl + H. 
 
 The valency of Na 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, ~N'd, or any other monad; oxygen, therefore, is 
 a dyad element. One atom of and two atoms of 
 H unite (H 2 0). 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 : 
 
 H 2 + E"a = H^aO + H. 
 
 One atom of Zn (65 parts by weight) requires 
 two molecules (73 parts by weight) of HC1 to sat- 
 isfy its combining power: 
 
 Zn + 2HC1 = ZnCl 2 + 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 + = ZnO. 
 
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 1 
 
 Bivalent elements, or dyads, as 0" 
 
 Trivalent elements, or triads, as.. ..Au m 
 
 Quadrivalent elements, or tetrads, as...C iv 
 Quinquivalent elements, or pentads, as..P v 
 
 Sexvalent elements, or hexads, as Cr vj 
 
 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 perissads, which means uneven. 
 
108 Inorganic Chemistry. 
 
 CHAPTER II. 
 
 GRAPHIC FORMULA. 
 Formula are sometimes written graphically, that 
 is, a number of lines or bonds, connecting the sym- 
 bols, indicating the equivalency of each; thus: 
 
 Hydrochloric acid, HC1 H— CI 
 
 Water, H 2 H— 0— H 
 
 Carbon dioxide, C0 2 0— C— 
 
 CI 
 
 Am. Chloride, NH 4 C1 H^NH 
 
 
 II 
 Nitric Acid, HN0 3 1ST— 0— H 
 
 II 
 
 
 
 
 II II 
 
 Zinc Nitrate, Zn(N0 3 ) 2 N— 0— Zn— 0— N 
 
 II II 
 
 
 
 These graphic formulae are often abridged by the 
 use of dots only, thus : 
 
 H.C1 H.O.II 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 HC1, H 2 0, CH 4 , C 2 H 6 , 
 etc.; or 1 triad atom, as Au Ui , and 3 monads, as in 
 AuCl 3 ; or 1 pentad and 5 monads, as in NTI 4 C1; 
 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 — II. So also the molecule of chlorine CI — CI ; 
 the molecule of phosphorus contains four atoms, 
 
 P=P As=As 
 
 So also the molecule of arsenic, 
 PpP- 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 : 
 
 Ordinary oxygen. Ozone. 
 
 The true equivalency of an element may be ex- 
 pressed as that which represents the maximum number 
 of monads atoms, with which one atom of it can com- 
 bine. The molecule, ammonium chloride, E"H 4 C1, 
 shows one atom of N 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 HgO 11 . 
 
 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 & 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 ZrST 2 ? a triad in ammonia NH 3 , and a pentad 
 in ammonium chloride NH 4 C1; sulphur is a dyad 
 in dihydrogen sulphide H 2 S, a tetrad in sulphurous 
 oxide S0 2 , and a hexad in sulphuric oxide S0 3 . 
 
 In compounds where the full valency of the ele- 
 ment is not exhibited, as in NH 3 , ammonia, the 
 two units belonging to N uncombined, probably 
 unite with each other, for the time being; but the 
 molecule of ammonia is willing to unite directly 
 with 1IC1, forming NH 4 C1, wherein the full va- 
 lency of ~N V is satisfied. Tetrad sulphur in S0 2 can 
 be oxidized into S0 3 , becoming thereby a hexad. 
 
 A perissad element is always a perissad; an 
 artiad element, always an artiad, inasmuch as vari- 
 
Chemical Philosophy. Ill 
 
 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 O u can enter the saturated molecule of water 
 
 H — H without disturbing the existing atomic 
 
 value of hydrogen, thus H — — 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 — — K, there 
 is a tetroxide of potassium K — O — — — — 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 4 ) ; 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 4 , carbon is a tetrad ; in ethane, 
 C 2 H 6 , carbon appears to be triad ; in ethene, 
 C 2 H 4 , it appears to be a dyad, and in ethine, 
 C 2 H 2 , a monad. The following diagrams will 
 readily explain the apparent discrepancy : 
 H H 
 
 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 (N& — Na), another change would occur, 
 2HC1 + Na— £Ta = 2NaCl + H— H. 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 2H atoms go free, 
 10 
 
114 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, tl — — II (water). 
 is a saturated molecule; if one of the hydrogen 
 atoms be removed, the resulting group, — — 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 : 
 ^a— Na + 2H-0— H — H— II + 2Na-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 — — — H, is a well known substance. 
 
Chemical Philosophy. 115 
 
 Compounds in general are often formulated so as 
 to show their molecular constitution by radicals. 
 Thus, nitric acid, ITN"0 3 , may be considered as con- 
 
 O 
 
 II 
 sisting of the 2 radicals, H— O— and 'N == HO.N0 2 . 
 
 II 
 O 
 
 Water is analogous in formula to sodium hydrate, 
 
 H.OH lS~a.OH. The graphic formula of phosphoric 
 
 Water. Sodium hydrate. 
 
 0— H 
 
 acid is O = 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 iv H 4 , is the typical saturated hydro-carbon. If 
 one of the four atoms of hydrogen be removed, 
 the residue will, of course, be C iv H' 3 , 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' 3 C1. Two atoms of hydrogen removed from 
 
116 Inorganic Chemistry. 
 
 methane, CH 4 , leaves the dyad radical methene, 
 CH r/ 2 , able to take up two atoms of chlorine to 
 form methene chloride, CH" 2 C1 2 . Three atoms of 
 hydrogen removed from methane, results in the 
 trivalent radical methenyl, CH r// , which in union 
 with three atoms of chlorine, produces methenyl 
 chloride, CHC1 3 (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, CC1 4 , or other monad element, 
 or by two dyad radicals, or by one triad and one 
 
 monad radical, 
 
 L. 
 
 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- 
 
 k 
 
 like an atom of oxygen — — , 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 
 
 I ' 
 H H-C-H 
 
 I I I 
 
 CH 4 or H— C— H + H— C— H= H— C— H or C 2 H 6 
 
 I I I 
 
 H H 
 
 Methane. Methene. Ethane. 
 
 Ethane, C 2 H 6 , is methane CH 4 , plus the dyad 
 radical CH 2 . If we presume to abstract one atom 
 of hydrogen from ethane, we will have the univa- 
 lent radical ethyl C 2 H r 5 , capable of joining itself 
 to an atom of chlorine, as in ethyl chloride 
 C 2 HVC1, or to hydroxyl, as in alcohol, C 2 H / 5 ^OH, 
 or two such groups, to — — , as in common ether 
 (CH 5 ) 2 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. 
 
 MATEEIA 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, incompatibles 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 Medica. 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 
 that 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 w T ater. 
 
 Chart., Charta; paper. 
 
 DiL, Dilutus; diluted. 
 
 F., Ft., Fiat; let a — be made. 
 
 Fl., Fluidus ; liquid. 
 
 Fob, Folium; a leaf, Folia; leaves. 
 
 Gr., Granum ; a grain. Grana; grains. 
 
 Gtt., Gutta; a drop : Guttse ; drops. 
 
 Hyd., Hydro ; water. 
 
 Hydr., Hydrargyrum ; mercury. 
 
 Inf., Infusum ; 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. 
 
 3^., Recipe; take. 
 
 Had., Radix ; root. 
 
 Rect., Reetificatus ; 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. Basis. 
 
 Sodii bi boras, aa 1.00 Gm. (gr. xv), Assistant. 
 Spts. rect., 4.00 CC. (f^i), Corrective. 
 
 Aq. rosce 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. 
 
 Lb. 1 
 
 Ounces. 
 
 Drachms. 
 
 Grains. 
 
 = 12 
 
 = 96 
 
 
 5760 
 
 S 
 
 = 8 
 
 = 
 
 480 
 
 
 Si 
 
 = 
 
 60 
 
 Fluid measure. 
 
 
 
 F, Ounces. 
 
 F, Dracnms. 
 
 
 Minims. 
 
 16 = 
 
 128 
 
 = 
 
 7680 
 
 fil = 
 
 8 
 
 = 
 
 480 
 
 
 f3l 
 
 = 
 
 rrv 60 
 
 Pint 
 ;Octarius). 
 
 01 = 
 
 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 jig- 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 weight, 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 fluigram 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). 
 
 Ln 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 (live cents). 
 
 If we regard the Gm or fGm, as corresponding 
 in this respect to our dollar, we 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 fluidime. The 
 fluidime may be considered the minimum quantity 
 for liquids, equal to 1J minims, and the mill, the 
 
124 Inorganic Chemistry. 
 
 smallest representative of weight, equal to fa of a 
 grain. 
 
 The prefixes used in the metric system are 
 sometimes convenient in speaking of weights and 
 measures, but in prescribing they 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). 
 
 & 0.001 (1 mill) 
 
 \ 0.03 (Scents) 
 
 1 0.00 (6 cents) 
 
 Ih 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 
 stud} 7 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 
 first 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 properties 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, aud 16 of zinc. Type 
 metal is an alloy of antimony and lead. Alloys 
 of mercury with other metals are named amalgams. 
 
 The melting point of an alloy is generally lower 
 than the mean melting point of its constituents. 
 For instance, tin melts at 235° (455 F.) ; bismuth, 
 melts at 264° (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 may be 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 susceptible 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 bluish 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, ^"a, Rb, 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 proper- 
 ties. Their carbonates are insoluble in water; they 
 each form but one chloride, which, as they are 
 dyads, is a dichloride (CaCl 2 ). 
 
 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, excepting silver chloride (AgCl), and mer- 
 eurous chloride (Hg 2 Cl 2 ), are soluble in water. 
 Metallic chlorides unite with certain oxides, form- 
 
130 Inorganic Chemistry. 
 
 ing oxy chlorides, and with organic bases, also, such 
 as aniline and the ptomaines. 
 
 Nearly 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 K 2 and CaO, do not decompose by heat alone; 
 others, as Au 2 3 , Ag 2 0, Pt0 2 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 V. 
 
 POTASSIUM. 
 
 Symbol, At. Wt. Sp. Gr. Valency, 
 
 K (Approx.) 0.87.50. I. 
 
 39. 
 
 Potassium occurs abundantly in nature, always 
 however in combination. It is an essential constit- 
 uent of animal and land 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. 
 
 KC0 3 + 2C == 3CO + 2K 
 
 The metal, being volatile, distills over, is passed 
 through naphtha, and condensed to proper form. 
 It melts at 62.5° (144.5F) ; 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— 0-11 + K = K-O-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, 
 K 2 0, 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 (milk of lime) on potassium 
 carbonate. 
 
 Ca(HO) 2 
 
 + K 2 C0 3 
 
 = CaC0 3 + 2KOH 
 
 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, K 2 C0 3 , is the familiar sub- 
 stance, potash. It is prepared from wood ashes, 
 and by various otber 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 2 C0 3 + H 2 00 3 = 2KHC0 3 
 
 Carbonic Potassium 
 
 Acid. Bicarbonate. 
 
 The bicarbonate is also called the hydrogen car- 
 bonate, and acid carbonate, although it is mildly 
 alkaline. 
 
 Potassium chloride, KC1, 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, KC10 3 , is prepared by passing 
 chlorine through a solution of the carbonate; or 
 through a solution of the chloride, containing milk 
 of lime. 
 KCl+3Ca(OH) 2 -f6Cl=3CaCl 2 H-3H 2 0+KC10 8 
 
 It is a colorless crystalline anhydrous solid, solu- 
 ble in 20 parts 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 instantaneous-Jight 
 matches. 
 
134 Inorganic Chemistry. 
 
 Potassium nitrate, KN0 3 , 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. 
 NaETo 8 + KC1 = NaCl + KN0 3 
 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 : 
 KN0 3 75 
 C 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 approximately 
 represented by the following equation : 
 
 2KN0 3 + 3C + S = K 2 S + 3C0 2 + 2N 
 
Potassium. 135 
 
 Potassium Permanganate, K 2 Mn 2 8 , 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 effects. 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 Gra. (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 efl'ect. 
 
 Most of the salts of potassium are diuretic and 
 slightly purgative. 
 
 The chlorate, in doses of 0.50 Om. (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 wash 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 Gm. 
 
 R. Potassii chloratis, 8 Gm. fen). 
 Aqua, 250.00 f Gm. (fgviij). 
 
 M. S. A gargle in stomatitis. 
 
 12 
 
138 Inorganic Chemistry. 
 
 CHAPTER VI. 
 SODIUM. 
 
 Symbol, At. Wt. Sp. Gr. Valency, 
 
 tfa. 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, NaCI, 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, Na 2 0, and 
 Na 2 2 , 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, Na 2 C0 3 , 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, Na 2 CO 3 ,10H 2 O, and is 
 the " sal soda" of the laundries. When devoid 
 of water, or dry carbonate, it is used in very large 
 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" Na HC0 3 , 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 Na 2 0,2B 2 3 , 10H 2 O borax, occurs 
 native, in colorless crystals, slightly effervescent, 
 and mildly alkaline ; soluble in water and glycer- 
 ine, but 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. 
 
 Labarraques Solution, liquor soda? chloratse, solu- 
 tion of chlorinated soda, NaCI, NaCIO, 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 bleaching agent, if combined with powdered 
 alum. 
 
 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, ) -,, AA n , ,. 
 
 Sochi Biboras, } L0 ° Gm ' ^ r ' xv) - 
 
 R. Sodii Boras, 4.00 Gm. (gi). 
 
 Mellis. 
 
 Aqua aa, 30.00 fGm. (fgi). 
 
 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 ; 
 caesium being the most highly electro-positive of 
 ail elements; they decompose water, setting hy- 
 drogen free, and form alkaline caustic hydroxides. 
 
 Ammonium, NH 4 , is a hypothetical, univalent, 
 
142 Inorganic 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, NH 3 , and other bodies 
 containing hydrogen. Thus, ammonia and nitric 
 acid, HN0 3 , unite with each other, without setting 
 
 any hydrogen free ; the hydrogen of the acid, 
 
 • 
 probably joins itself most intimately to theNH 3 , to 
 
 form the radical NH 4 , which then, like an atom of 
 
 potassium, unites with the electro-negative radical, 
 
 no 3 . 
 
 NH 3 + HF0 3 = NH 4 ,N0 3 
 
 Ammonia. Nitric Acid. Ammonium 
 
 Nitrate. 
 
 Ammonium salts are numerous, and resemble in 
 many respects the corresponding salts of the alkali 
 metals. The hydroxide, JSTH 4 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, NH 4 C1, 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 barns 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, CaCl 2 , 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, C0 2 + Heat = CaO + C0 2 
 
 Calcium Calcium 
 
 Carbonate Oxide 
 
 (Lime) 
 
 Lime is a hard, infusible, white solid. When 
 slaked with water, which union develops great heat. 
 Calcium hydroxide, Ca(HO) 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 C0 2 
 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 C0 2 , 
 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 mouth, 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 occurs in nature as alabaster and 
 selenite and en masse as gypsum, CaS0 4 , 2H 2 0. 
 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, Ca 3 (P0 4 ) 2 , bone phosphate, is 
 found in natural deposits in certain portions of 
 South Carolina, Florida, and the islands of the 
 Carribean sea, supposed 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, CaF 2 , fluor spar, constitutes 
 about two per cent, of human bone and enamel. 
 
 Chlorinated Lime, CaCl 2 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. 
 
Calcium, Etc. 147 
 
 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 fGra. (f^ij). 
 
 Creta Prseparata, 1.00 Gm. (gr.xv). 
 
 Calcii Phosphas. Prsecipitata, 1.50 Gm. (gr. xx). 
 
 R. Calcii phos. prsecipit, 4.00 Gm. (gi). 
 Mistura Cretse, 125.00 fGra. (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(N0 3 ) 2 is used 
 in making "red fire," barium nitrate Ba(N0 3 ) 2 
 in making "green fire.' 1 Barium salts are used as 
 a test for sulphuric 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 Ba0 2 . This dioxide readily 
 gives up O, as in the manufacture of hydrogen di- 
 oxide, already alluded to. 
 
148 Inorganic Chemistry. 
 
 CHAPTER Yin. 
 
 METALS OF THE EARTHS, AND SILVER. 
 
 The metals of the earths — yttrium, erbium, 
 samarium cerium, etc. — are quite numerous, but 
 are found only i'n a few rare minerals, principally 
 as silicates. They, and nearly all their com- 
 pounds, are mere chemical curiosities, except 
 cerium oxalate, Ce 2 (C 2 4 ) 3 , which is used in 
 medicine. 
 
 SILVER. 
 
 Symbol, At. Wt. Sp. Gr. Yalency, 
 Ag. 108. 10.5. I-III. 
 
 Silver has been known from the earliest times. 
 It is found in various countries, in the metallic 
 state, hut 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 commerciaj 
 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 air, although traces of II 2 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. + HM) 3 = Ag^0 3 + H. 
 
 Silver Nitrate AgN0 3 , 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, indelible 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 aqueous 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 2 0, 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 Gm. (gr. £). 
 Antidote, common salt. 
 
 R. Argenti Nitras, 0.10 Gm. (gr. jss). 
 Aqua Desk, 30.00 f Gm. (fgi). 
 
 M. S. Injection in diseased antrum. 
 
152 Inorganic Chemistry. 
 
 CHAPTER IX. 
 
 COPPER, MERCURY. 
 
 Symbol, At. Wt. Sp. Gr. Valency, 
 Cu. 63. 8.95. II. 
 
 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 of 
 N 2 2 . It also forms salts with dilute acetic acid' 
 and hot sulphuric acid, and slowly, with dilute 
 hydrochloric and sulphuric and carbonic acids, al- 
 kalies and saline solutions. All soluble 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 cupric and 
 cuprous. 
 
 Cupric chloride, CuCl 2 , obtained by dissolving 
 cupric 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, CuCl 2 , 2H 2 3 . When 
 heated it loses all its water of crystallization, and 
 half its chlorine, and is converted into cuprous 
 chloride, Cu 2 Cl 2 , 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 
 phosphoric acid it forms a hard, tenacious, insol- 
 uble, black mass, which combination has been 
 introduced by Dr. W. B. Ames, as a filling imate- 
 rial in posterior teeth, for setting crowns, etc. The 
 mineral libethenite is HCu 2 P0 5 . 
 
 Cuprous oxide Cu 2 0, 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, CuSo 4 ,5H 2 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. 
 
 Matekia 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. £). 
 
 MERCURY. 
 
 Symbol, At. Wt. Sp/Gr. Valency, 
 Hg. 200. 13.59. II. 
 
 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 (andF) 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 
 by the atmosphere, but near its boiling point it 
 slowly absorbs oxygen, passing into the red oxide, 
 HgO. 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 
 so 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 black, the better the preserving qualities. 
 
 Mercuric chloride, HgCl 2 , bichloride of mercury, 
 corrosive chloride, corrosive sublimate, etc., is usu- 
 ally prepared by subliming a mixture of sodium 
 chloride and mercuric sulphate. 
 
 2NaCl + HgS0 4 = Na 2 S0 4 + HgCl 2 
 
 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, Hg 2 -Cl 2 , 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 + HgS0 4 + Hg = Na,S0 4 + Hg 2 Cl a 
 
 Mercurous 
 Chloride. 
 
 A heavy white, fine powder condenses, insoluble 
 in water, and alcohol, tasteless, and decomposes 
 slowly in sunlight into free Hg andHgCl 5 . 
 
 Mercuric oxide, HgO, occurs in red scales, when 
 mercury is heated in air, commonly as red precipi- 
 tate. It forms with acids, mercuric salts. 
 
 Mercurous oxide, Hg 2 0, 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 the brilliant red pigment, 
 vermilion. 
 
 Mercurous sulphide Hg 2 S, is a black powder, 
 known as ethiopes mineral. 
 
 f CI 
 Mercuric ehloramide, Hg < -j™- 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 
 filling. 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 would 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 
 
Mercury. 159 
 
 sometimes following their use. Antidote to mer- 
 curic chloride — emesis, albumen, white of egg, 
 milk, flour. 
 
 Dose. Mercuric Chloride, 0.004 Gm. (gr. ■£%). 
 Mercurous Chloride, 0.30 Gm. (gr. v). 
 
 B. Hydrarg Chlor. Corrosiv. 0.10 Gm. (gr.jss). 
 Acidi Hydrochlorici Dil., q. s. ad. solve. 
 Mellis Depurati, 15.00 fGm. (f^ss). 
 Aqua Dest., q. s. 150 fGm. (fg v). 
 
 M. S. To be used as a wash, or gargle, in syphilitic 
 ulceration of mouth and throat. 
 
160 Inorganic Chemistry. 
 
 CHAPTER X. 
 
 ZINC, ETC. 
 
 Symbol, At. Wt. Sp. Gr. Valency, 
 Zn. 65. 7. II. 
 
 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 = C0 2 + 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 ehloride, ZnCl 2 , is made by direct action of 
 chlorine upon zinc, or by dissolving gran alated zinc, 
 or zinc carbonate in hydrochloric acid, purifying 
 by solution of chlorine and zinc carbonate, and 
 evaporating the solution to dryness. It occurs as 
 a grayish-white translucent, crystalline 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. (3 ijjss) of zinc chloride 
 to 30.00 f Gm. (f§i) 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 C0 2 are driven off. 
 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, H 3 P0 4 , prepared by dis- 
 solving pure glacial phosphoric acid, HP0 3 , iu 
 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, amides, 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 sulphate, ZnS0 4 7H 2 0, 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 Medioa. Zinc chloride is a powerful 
 caustic, owing to its dehydrating qualities. It is 
 employed in substance, or strong solution, for treat- 
 ment 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.) 
 
 Zinc Sulphate 0.06-0.30 Gm. (gr. j-v.) 
 
 As an emetic — Zinc Sulphate 0.65 Gm. (gr. x.) 
 
 Antidote, Sodium bicarbonate. 
 
 R. Zinci Chloridi 0.06 Gm. (gr.j). 
 Aqua Rosae 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, bat is always 
 found in nature in combination. The double car- 
 bonate of magnesium and calcium MgCa2C0 3 is 
 known as dolomite or mountain limestone, of which 
 whole mountain ranges are formed. The metal 
 also occurs in the single corbonate, the sulphate, 
 hydrate, nuo-phosphate, chloride and several sili- 
 cates, of which latter class, meerschaum is one 
 (2MgO Si0 2 ). 
 
 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 
 
 MgCl 2 + 2£Ta = 2£TaCl + Mg 
 
 Magnesium 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 4 7H 2 0, 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 MgS0 4 7H 2 0, 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° 
 (392F). This last is known as water of constitution, 
 and may be replaced by certain sulphates, as for 
 instance K 2 S0 4 , yielding a double sulphate. 
 
166 Inorganic Chemistry. 
 
 MgS0 4 ,H 2 6H 2 + K 2 S0 4 = Mg{|^| } 6S0 4 
 
 I TI O Potassio-Magnesium 
 
 ~r xx 2 w 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 
 
 Fe{^|}6H 2 
 
 Pot&ssio-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- Glucinum. 167 
 
 but of no importance, except as a constituent of 
 some fusible, and amalgam alloys. 
 
 Beryllium or Glucinum. (Gil), is a rare metal, 
 occurring in certain silicic minerals, and as an alu- 
 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, 
 glucinum. 
 
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, however, 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 
 
Lead, 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, 2PbC0 3 , (HO) 2 ,is the basij3 of the well- 
 known paint, white lead. The monoxide, PbO, is 
 known as litharge, and this, if heated in a current 
 of air, is converted into red lead, Pb 3 4 . 
 
 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(C 2 H 3 2 ) 2 , sugar of lead, is sometimes given 
 internally as an astringent, in diarrhoea and 
 hsemoptyses. 
 
 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 Thallium (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, 
 Sn. 
 
 At, Wt. Sp. Gr. 
 1.18. 7.29. 
 
 Valency, 
 II-IV. 
 
 Tin is one of the metals of earliest antiquity. 
 The principal ore of tin is the mineral cassiterite 
 
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, Sn0 2 -\- C = C0 2 -f- 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 which 
 exists in, and preserves, galvanized iron, (iron and 
 zinc). 
 
 There are two sets of tin compounds. The two 
 
172 Inorganic Chemistry. 
 
 chlorides, viz. : SnCl 2 and SnCl 4 , 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- 
 spectivety, 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. 
 
 Stayinic oxide, Sn0 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 
 putty 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. OrthostsLumc acid, 
 
 H 4 Sn0 4 , has four hydroxyl groups in its molecule ; 
 
 all its oxygen has a linking function, as the graphic 
 
 formula will show : 
 
 0— II 
 
 _0_Sn_ 0—H 
 -H 
 
 — Sn — being a tetrad, requires four groups of 
 
 i 
 
Tin. 173 
 
 hydroxyl (0H) 4 , to satisfy its equivalency of 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 v . 
 Ortho-phosphoric acid should therefore have Jive 
 hydroxyl groups P(OH) 5 . 
 
 Meta-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, H 2 SnO s , is ortho-stannic acid, 
 minus one molecule of water: 
 
 O-H 
 
 I II 
 
 H-O-Sn-O-H H— O-Sn 
 
 I I 
 
 O-H O-H 
 
 Ortho-Stannic Acid. Meta-Stannic Acid. 
 
 Where two molecules of water can be removed 
 from an ortho-acid, a dimeta-acid results ; three mole- 
 cules of water removed, a trimeta-acid, etc. 
 
 O-H 
 
 I II 
 
 H-O-^P -O-H H-0\ p 
 
 H-O^ ^-O— fl H-O-^^O-H 
 
 Ortho-phosphoric Acid. Meta-phos. Acid. 
 
 
 
 II 
 
 H-0-P=0=HP0 3 , etc. 
 
 Dimeta-phos. Acid. 
 
174 Inorganic Chemistry. 
 
 The salts of ortho and meta-acids are named with 
 corresponding prefixes. 
 
 Stannic sulphide, SnS 2 ,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. 
 
Aluminum. 175 
 
 CHAPTER XII. 
 
 ALUMINUM, ETC. 
 
 Symbol, At. Wt. Sp. Gr. Valency, 
 
 Al. 27. 2.6. IV. 
 
 t 
 
 Aluminum tiext 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, emery, 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 
 methods adopted, for obtaining the metal. 
 A1 2 C1 6 + Na 6 = 6KaCl + 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 receiving a high polish ; is very malle- 
 
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 success, 
 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, have taken an 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, A1 2 (S0 4 ) 3 ,K 2 S0 4 ,24H 2 0, or Al 2 
 K 2 (S0 4 ) 4 ,24H 2 0. Ammonium alum is A1 2 (KH 4 ) 2 
 (S0 4 ) 4 ,24H 2 0. There are alums also of Na,Cs, 
 Kb, Ag, and Tl, wherein these elements respect- 
 ively occupy the place of K or NH 4 ; 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, 
 A1 2 (S0 4 ) 3 , is formed. This is then added in solu- 
 tion, to a solution of potassium sulphate K 2 S0 4 , 
 Or ammonium sulphate NH 4 S0 4 , 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, A1 2 3 , 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 mixing a solution of alum with 
 excess of ammonia), presents a white, tasteless, co- 
 herent mass, very slightly affected by acids, and 
 fusible only in the oxyhydrogen flame. 
 
 The hydrate Al 2 (HO) 6 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, 
 JSTa 6 Al 2 6 . There are also the mono-meta hydrox- 
 ide, Al 2 0(HO) 4 , and the dimeta-hydroxide, A1 2 2 
 (HO) 2 , forming with bases, mono-meta and dimeta- 
 aluminates, respectively, as dimeta-potassium alu- 
 minate, K 2 A1 2 4 , etc. Aluminum hydrates are 
 largely used in calico printing, as mordants, inas- 
 much as they are able to unite with organic dye- 
 stuff's, to form "lakes," which are insoluble; the 
 
Aluminum. 179 
 
 different colors being thus "fixed" in the fiber of 
 the cloth. 
 
 There are normal, and basic (t. e., containing hy- 
 drogen), aluminum phosphates found in nature, of 
 which, the turquoise, A1 4 (P0 4 ) 2 , (HO) 6 ,2H 2 0, 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 un- 
 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 heing 
 translucent, and differs from glass in being non-. 
 transparent, and much more infusible. 
 
 Porcelain clay, or kaolin, is a hydrous aluminum 
 silicate — , H 2 Al 2 Si 2 8 ,H 2 0, derived by atmos- 
 pheric influence on felspar, which is K 2 Al 2 Si 6 16 . 
 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 body consists chiefly of felspar, kaolin and silica 
 (Si0 2 ); 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 Labarragues solution, makes an ef- 
 fective bleacher for discolored teeth. 
 
 Aluminum chloride, sulphate, and acetate, are dis- 
 infectants 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. fei). 
 
 Tinctura myrrhse, 15.00 fGm. (f^ss). 
 Aq. Dest. q. s. ad. 60.00 fGm. (fgij) 
 
 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 them 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, IY, 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), Fe 3 4 ; ferric 
 hydrate (limonite), 2Fe 2 3 3H 2 0; ferric oxide (he- 
 matite), Fe 2 3 ; and ferrous corbonate (siderite), 
 FeC0 3 . Those ores that are not native oxides, 
 are converted into artificial oxides by roasting, so 
 that practically, the chemical process of producing 
 
184 a Inorganic Chemistry. 
 
 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: 
 
 Fe 2 3 + 3C = 3CO + 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 oft' 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 oft* 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 would 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, FeSo 4 ,7H 2 0, commonly called 
 green vitriol, or copperas. 
 
 Ferrous Chloride, FeCl 2 , and ferrous iodide, Fel 2 , 
 are pale green, and soluble. Ferrous sulphide, FeS, 
 made by fusing iron and sulphur together, dissolves 
 in dilute acids, with evolution of H 2 S. 
 
 Ferrous Carbonate, FeC0 3 , a white precipitate, 
 produced when solution of a ferrous salt, as FeS0 4 , 
 is added to a solution of an alkaline carbonate, as 
 16 
 
186 Inorganic Chemistry. 
 
 Na 2 C0 3 , on exposure to the air, this ferrous car- 
 bonate decomposes into free C0 2 , and Fe 2 3 ; the 
 latter substance is known as "jeweler's rouge" 
 (polishing powder), and as the pigment, " Venitian 
 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, Fe 2 3 , sesqui oxide of iron, may be 
 considered the basis of the ferric salts. The oxide 
 itself has been sufficiently described. 
 
 Ferric Chloride, Fe 2 Cl 6 , 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, Fe 2 (HO) 6 , 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, FeS 2 , iron pyrites, sometimes 
 
Iron. 187 
 
 called " fools gold," is used in the manufacture of 
 copperas and of sulphuric acid. 
 
 Ferric sulphate, Fe 2 (S0 4 ) 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 2Fe 2 3 ,(S0 4 ) 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, Fe 2 3 , 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 hae- 
 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, ; in- 
 asmuch as they undoubtedly corrode the teeth. 
 
 The princinal 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. 189 
 
 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. 
 
 IRON— 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 
 (Fe 2 3 ). 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 C0 2 . Now, 
 C0 2 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 2 =FeC0 3 . 
 
 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 C0 2 
 escaping in the respiratory exhalation, while the 
 FeO takes up with the oxygen present, 2FeO-f- 
 0=Fe 2 3 . 
 
 Such, 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 oxygen 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 C0 2 , 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 presence, 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 Inorganic Chemistry. 
 
 If C0 2 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 C0 2 , or of its temporary 
 retention throughout the tissues ; and we 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 energj' 
 
Iron. 193 
 
 than in the air, the heat setting the oxygen free, 
 oxide compounds only resulting. It has also been 
 ascertained, that when inhaled, N 2 dissolves in 
 the arterial blood, unchanged. In this way it 
 supersedes the legitimate carrier of oxygen, Fe 2 3 , 
 and the latter compound, not being allowed to de- 
 compose, in the capillaries, into ferrous oxide, FeO, 
 the C0 2 that is formed, in much greater abun- 
 dance than usual, by the oxygen of the N~ 2 0, 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, 
 anaesthesia, and finally a state of carbon dioxide as- 
 phyxiation, which are observed to take place when 
 N 2 is 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 C0 2 , in quantity necessary for the purpose, 
 the danger line moving to and fro, according to 
 the individual. The relative immunity from danger, 
 with N 2 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, C0 2 , 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, VI. 
 
 Manganese is closely related to iron. It occurs 
 somewhat abundantly, mainly as an oxide, Mn0 2 , 
 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, Mn0 2 , Mn 2 3 , 
 and Mn 3 4 , 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, H 2 Mn 2 8 , 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 
 
 R 2 Mn 2 8 , prepared by mixing manganese dioxide, 
 potassium chlorate and potassium hydrate in a 
 little 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. hi 
 
 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, Co 3 S 4 ; 
 as an arsenide, Co 2 As 6 ; as an arsenate, Co 3 
 (As0 4 ) 2 8H 2 ; as speiss-cobalt, CoE~iFeAs 2 ; 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, CoCl 2 , in water, furnishes sympa- 
 thetic ink of a blue color, when heated, but which 
 becomes invisible on cooling, by absorption of 
 moisture. 
 
 Nickel is always a constituent of meteoric iron. 
 
196 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 (NH 4 ) 2 Ni(S0 4 ) 2 , 
 6H 2 0, 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 XV. 
 
 ARSENIC. 
 
 Symbol, At, Wt. Sp. Gr. 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, arsenates, 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 __]J inasmuch as its va- 
 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 arsme, AsH 3 , 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 SbH 3 , but the deposited 
 arsenic is soluble in sodium hypochlorite solution, 
 whereas the antimony is not. It is said that 50 \ 
 of a grain of arsenic can be detected in this way. 
 Two oxides of arsenie, and their corresponding 
 acids are known. 
 
 As 2 3 + 3H 2 = 2H 3 As0 3 
 
 Arsenous Water. Arsenous 
 
 Oxide. Acid. 
 
 As 2 5 + 3H 2 = 2H 3 As0 4 
 
 Arsenic Arsenic 
 
 Oxide. Acid. 
 
 Arsenic compounds are not so poisonous as the 
 arsenous, and not so important. 
 
 Arsenous oxide, As 2 0, 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 Na 3 As, as a mordant is used in calico print- 
 ing; and the brilliant pigment, Paris-green, a 
 double salt of copper arsenite and copper acetate, 
 Cu 3 As 2 Cu(C 2 H 3 2 ) 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, AsCl 3 , is 
 obtained. 
 
 The 2 sulphides of arsenic, As 2 S 2 , As^S 3 , are 
 known as the minerals, red realgar, and golden-yel- 
 low orpiment, respectively. 
 
200 Inorganic Chemistry. 
 
 Materia Medica. — The official name of arsenous 
 oxide, As 2 3 , 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 
 sanclorac 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 
 arsenic burn 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 primes vice, exalting 
 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.(n^ ij-v). 
 Acidum Arsenosum, 0.001-0.006 Gm. (gr. ^, ^). 
 
 R. Acidi Arseniosi, 8.00 Gm Qjij). 
 
 Cocaini 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— V. 
 
 Antimony is not an abundant metal, although 
 
Arsenic. 203 
 
 comparatively 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, Sb 2 S 3 +Fe 3 =3FeS + 2Sb; or 
 by 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 fire 
 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, which 
 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 Sb 2 3 , Sb 2 4 , 
 Sb 2 5 . The trioxide and pentoxide, like those of 
 nitrogen are acid oxides, but their acids HSb0 2 , 
 HSb0 3 , unlike those of nitrogen, are very weak. 
 There is also an ortho-antimonic acid, H 5 Sb0 5 , 
 and an ortho-antimonous acid, H 3 Sb0 3 . 
 
204 Inorganic Chemistry. 
 
 Antimony and potassium tartrate, is a salt known 
 as " tartar-emetic." 
 
 Antimonous chloride, SbCl 3 , is the " butter of 
 antimony," which is changed by water, into an 
 oxychloride, SbCl 3 + H 2 = 2HC1 + SbOCl. 
 
 Antimony oxysulphide, Sb 2 2 S 2 , imparts a yel- 
 low tint to glass and porcelain. The nature of 
 H 3 Sb was sufficently indicated in the preceding 
 chapter. 
 
Bismuth. 205 
 
 CHAPTER XVI. 
 
 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 rhombohedrons, 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 Jy of 
 its bulk, making a sharply defined cast when 
 poured into a mold. 
 
 Bismuth 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, BiCl 3 ; the oxide, 
 Bi 2 3 ; the sulphate, Bi 2 (S0 4 ) 3 , and the nitrate, 
 Bi(N"0 3 ) 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, H 2 Bi0 2 
 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, 
 BiCl 3 , a white precipitate of bismuth oxycloride 
 results. BiCl 3 + H 2 = 2HC1 + 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, BiCl 3 -f- 
 3KOH = 3KC1 + 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 the oxychloride. This hydrated oxide, BiO(HO), 
 is basic to strong acids, as sulphuric, etc., and 
 acid to strong bases , as sodium, etc.; for example, 
 NaBi0 2 , sodium bismuthate. 
 
 Materia Medica. — Bismuthi sub-nitras is em- 
 ployed locally, in powder, alone, or with charcoal, 
 in cancrum oris, and other forms of ulceration 
 of the mouth, in intertrigo, and as a snuff 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 Gra. (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, V 2 0, V 2 2 , V 2 B , V 2 4 , and V 2 5 . 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. Nio- 
 bium is also known by the better name, Columbium. 
 
 Molybdenum, Tungsten. 
 
 Symbol, At. Wt. Sp. Or. Valency, 
 Mo. 96 8.6 VI. 
 
 Molybdenum is another rare element, occurring 
 in small quantity, as a sulphide, MoS 2 , and as lead 
 molybdenate. It is a white, brittle metal, almost ab- 
 solutely infusible. When heated in air, it oxidizes 
 to molybdic oxide, Mo0 3 , analogous to sulphuric 
 oxide, S0 3 ; molybdic acid, H 2 Mo0 4 , is analogous 
 to sulphhuric acid, H 2 S0 4 . 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, 
 FeW0 4 , in the mineral ioolfram f 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, W0 3 . A small addition of tungs- 
 ten to steel, is said to confer on the latter, extraor- 
 dinary hardness and fineness. 
 
Uranium. 209 
 
 The oxide, ¥0 3 , is an acid oxide, the corre- 
 sponding acid having the formula, H 2 W0 4 . The 
 tungstate of the alkali metals (more especially of 
 sodium, Na 2 ¥0 4 ), 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 the uranous compounds, as 
 UC1 4 , U0 2 , U(S0 4 ) 2 , etc., and sexvalent in the 
 uranic compounds. In the uranic salts the bivalent 
 radical uranyl, U0 2 , is supposed to be the electro- 
 positive radical, as in uranic oxide (uranyl oxide), 
 (U0 2 )0; also (TT0 2 )C1 2 , (C0 2 ),2X0 3 ), (IT0 2 )S0 4 ). 
 18 
 
210 Inorganic Chemistry. 
 
 There is no uranic chloride (UC1 6 ), or bromide, etc., 
 as with tungsten. 
 
 Alkaline bases form salts with uranic oxide, 
 U0 3 , known as uranates ; thus, Sodium Uran- 
 ate, Na 2 0, 2U0 3 , and Ammonium Uranate, 
 Am 2 0,2U0 3 , 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. VI. 
 
 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, FeCr 2 4 . 
 
 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, CrCl 2 , is one of the most 
 powerful reducing agents known. It precipitates 
 gold frum solution of auric chloride. 
 
 Chromic Chlroide, Cr^-Clg, occurs in crystal- 
 line plates of a pale violet color. Its hydrate, 
 Cr 2 Cl 6 9H 2 0, 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, Cr 2 3 , 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, Cr0 3 , 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. 
 
 CrOg + H 2 = H 2 Cr0 4 
 
 (Chromic Acid.) 
 
 With potassium, for example, it forms the normal 
 salt, K 2 Cr0 4 , and by addition to this, of one more 
 molecule of CrO B , we have potassium pyrochro- 
 mate or dichromate. 
 
 K 2 Cr0 3 + Cr0 3 = K 2 Cr 2 7 . 
 
 This salt is better known as bi-chromate of potash. 
 It occurs in 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(CrO s ) to K 2 Cr0 4 , 
 we have K 2 Cr 3 O 10 . 
 
 Plumbum chromate, PbCr0 4 , is " chrome yel- 
 low," which, by boiling with caustic alkali is con- 
 verted into PbCr0 4 ,PbO, "chrome red;" and 
 " chrome orange " is a mixture of these, the orange 
 ray being intermediate between yellow and red. 
 
Chromium. 213 
 
 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 
 whenever used in the mouth, in treatment of phag- 
 edenic ulcers, etc., it should be in suitable dilu- 
 tion, and very carefully applied. 
 
2 14 Inorganic Chemistry. 
 
 CHAPTER XVII. 
 GOLD, ETC. 
 
 Symbol, At. Wt. Sp. Gr. Valency, 
 
 Au. 96.5. 19-4. I-III. 
 
 G-old, 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 quartation, 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., 
 gives 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 prermred 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 unaffected by the air, sulphuy- 
 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 + 4IIJTO, = 8H,0 + 4NOC1 -f 8C1. 
 6C1 + Au + Cu -f Ag = AuCl 3 + CuCl 2 + 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 : 
 6FeS0 4 + 2AuCl 3 = 2Fe 2 (S0 4 ) 3 + Fe 2 Cl 6 +2Au. 
 
 or, 
 
 3H 2 C 2 4 + 2AuCl 3 = 6C0 2 -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. Niter, 
 (KN0 3 ), 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 2 ). When sulphur is needed in the, pro 
 cess, it is furnished by the crude antimonium sul- 
 phide (Sb 2 8 3 ). The disengaged sulphur forms sul- 
 phides of the base metals present; the antimony 
 alloys with the gold, and is afterward driven off 
 from the latter, by heating in an excess of air. 
 
 The chemical compounds of gold are neither nu- 
 merous nor important. 
 
 Auric chloride, AuCl s , 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, asNaCl, AuCl s , 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, Au 2 3 , 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 
 as a dark brown powder, easily decomposed by 
 light and heat. It acts generally as an acid oxide, 
 uniting with bases to form aurates thus 
 
 K 2 + Au 2 3 = 2KAu0 2 
 
 Potassium Aurate. 
 
 Ammonium aurate, obtained by digesting auric 
 oxide in ammonia, is known as fulminating gold, 
 a dangerous explosive, NH 4 , Au0 2 . 
 
 Aurous oxide, Au 2 0, is a greenish powder. Pur- 
 ple of Cassiush probably a compound of this oxide, 
 with the two oxides of tin, obtained by reaction 
 between aaric 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 " (Au 2 OSn 3 5 ), 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 ^'-chlo- 
 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. ^o)- 
 
 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 (AuCl 3 ), 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 4 ), instead of gold solution, has been found 
 by Professor M. to be effective in forming a surface 
 of platinum, 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-IV. 
 
 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 Inorganic Chemistry. 
 
 poor conductor of heat and electricity : it melts at 
 the temperature of the oxyhydrogen name. , 
 
 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 still, platinum 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, PtCl 4 , 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, &s 2KC1, PtCl 4 . 
 
 Platinous Chloride, PtCl 2 , 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, PtCl 2 . 
 
 Platinic oxide, Pt0 2 , 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 JKH 3 C1 
 
 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, negative. Positive electricity passes from 
 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 rheophones 
 (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 fg), potassium dichromate, 
 230 Gm. (7 5). Dissolve the latter in boiling 
 
226 Inorganic Chemistry^ 
 
 water, 675 CC (1.36 pints), and when cool, add to 
 the acid mixture. 
 
 The poles 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 : 
 
 I HH } { HH } { HH } { HH } { HH } { HH } 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. 
 
 ctro-negative. 
 
 
 
 
 
 
 B 
 
 Sn 
 
 Ba 
 
 s 
 
 C 
 
 Pb 
 
 Li 
 
 ¥ 
 
 Sb 
 
 Co 
 
 Na 
 
 F 
 
 Si 
 
 m 
 
 K 
 
 CI 
 
 H 
 
 Fe 
 
 Rb 
 
 Br 
 
 An 
 
 Zn 
 
 Cs 
 
 I 
 
 Pt 
 
 Mn 
 
 Electro-positive, 
 
 Se Hg Al 
 
 P Ag Mg 
 
 As Cn 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 
 thin est film of ice is sufficient to arrest the elec- 
 tric decomposition of water. Mere solution, or 
 fusion by heat, will accomplish the object. But 
 all liquids 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- 
 dered 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, H 2 S0 4 ),is split up into free hydrogen, which 
 appears at the negative electrode, and sulphione, 
 S0 4 , which appears at the positive electrode. In 
 the same manner cupric sulphate, CuS0 4 , splits up 
 into metallic copper and sulphione, S0 4 ; the S0 4 
 loses an atom of oxygen, which escapes, and the res- 
 idue, S0 3 , unites with water to become H 2 S0 4 . 
 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, whicli will unite with the 
 acid present, to reproduce the typical salt. 
 
 2KOH + H 2 S0 4 = K 5 S0 4 2H 2 0. 
 
 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, AuCl 3 , 
 and solution of potassium cyanide, KCN, 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 with graphite, which serves as a 
 conductor, outlining the size of the plate 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, AgCN, 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 sufficient 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, 
 Pb0 2 ,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 hy Priestly, in 
 1775, lent a fresh impetus to these studies. 
 
 G-uyton 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, 114, 016, F19 — 
 
 3. Na23, 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. 
 E represents one atom of any element, as RO 
 means one atom, united to one of oxygen, or R 2 0, 
 two atoms, etc. 
 
236 
 
 Inorganic Chemistry. 
 
 03 
 
 > 
 
 1 o 
 1 « 
 
 II 
 II 
 
 OS 
 1 ° 
 
 oo 
 
 I s 
 
 1 <o 
 
 1 iO 
 
 3 
 ft 
 
 o 
 
 i "3 
 
 0, 
 
 1 O 
 
 1 1 
 
 3 
 
 II 
 
 1 1 
 1 1 
 
 lO 
 OS 
 
 o 
 
 eo 
 1 os 
 
 1 1 
 1 1 
 
 1 1 
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 > 
 
 
 o» 
 
 in 
 
 iO 
 
 eo 
 5 
 
 a 
 3 
 
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 00 
 
 m 1 
 
 tH i-H 
 CO 
 
 II 
 
 1! 
 
 > 
 
 Eo 
 
 eg 
 O 
 
 cn 
 
 CO 
 
 co 
 cm 
 
 a 
 
 V 
 
 CO 
 
 CO 
 
 o» 
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 3 
 
 1 
 
 H | 
 
 r 
 
 
 p 
 
 > 
 
 
 
 CO 
 
 lO 
 
 l> 
 
 00 
 
 -< 
 
 CT> 
 
 om 
 
 to 
 
 w 
 
 co 
 
 "3 
 
 H 
 
 1 
 
 s l 
 
 > 
 
 WO 
 
 1 °* 
 
 1 3 
 
 oo 
 H 
 
 CO 
 
 (NO 
 
 t>o> 
 
 C3N 
 
 coo 
 
 r-l Tj< 
 
 coo 
 
 II 
 
 s 
 
 Ph 
 
 eo 
 
 CO 
 CN 
 
 g 
 
 IO 
 
 i-( 
 
 PQ 
 
 -<* 
 o 
 
 CO 
 
 < 
 
 o> 
 
 00 
 OS 
 
 co 
 
 OS 
 
 O 
 
 
 eo 
 
 l S 
 
 <N 
 
 - 
 
 l« 
 
 1 °> 
 l« 
 
 1 
 
 O 
 
 <N 
 
 be 
 
 CO 
 
 «a 
 
 <o 
 
 eo 
 
 PQ 
 
 O 
 
 li 
 
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 CN ' 
 
 be 
 
 w 
 
 M 
 
 
 ■ w3 
 
 CO 
 CN OJ 
 
 ajco 
 
 CO 
 CO 
 
 3 
 O 
 
 i« 
 
 CO 
 
 co 
 
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 'So 
 eo 
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 II 
 
 to 
 o> 
 
 < 
 
 
 ad 
 o 
 "C 
 
 CO 
 
 .H N 
 
 CO •*■ 
 
 into 
 
 t- 00 
 
 oo 
 
 iH !N 
 
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-boron — 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 oxygen, 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 
 on 1 ' 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 name 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. Nitrogen 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 
 Bnnsen 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 
 
Spectrum Analysis. 241 
 
 of an absolute continuous band of light, ranging 
 from red to violet, but is seen to be interpersed 
 by hundreds of dark 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 bright 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 lime 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, therefore, 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 Inorganic Chemistry. 
 
 The physical condition of the sun is at once in- 
 dicated by these experiments of Kirchoff. 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 nebula , 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. 
 
PART 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 H 2 
 and CO 2 ; 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 in 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 
 average 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. Antiseptics 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 of fumigating, 
 by burning sulphur, the freshly formed sulphurous 
 oxide (S0 2 ), 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 month, 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. We 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 nitrogen, phos- 
 phorus, and sulphur; also the haloid elements and 
 various metals. 
 
 Methane, CH 4 , 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 CH 2 " to form C 2 H 6 , as may be easily un- 
 derstood by the graphic formulas. 
 
 H H H H 
 
 1 I II 
 
 H— C H(CH d ) + — C— (CH 2 ) == H— C— C— H (C 2 H 6 ) 
 
 H H H H 
 
 Methane. Methene. Ethane. 
 
 On the other hand, methane, CH 4 , 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 4 
 
 CH 2 
 
 
 
 Methane. 
 
 Methene. 
 
 
 
 C 2 H 6 
 
 Ethane. 
 
 C 2 H 4 
 
 Ethene. 
 
 ^2^2 
 
 Ethine. 
 
 
 C 3 H 8 
 
 Propane. 
 
 C 3 H 6 
 
 Propene. 
 
 C 3 H 4 
 
 Propine 
 
 C 3 H 2 
 
 Propone. 
 
 C 4 H 10 
 
 Quartane. 
 
 C 4 H 8 
 
 Quartene. 
 
 C 4 H 6 
 
 Quartine. 
 
 C 4 H 4 C 4 H 2 
 
 Quartone. Quartune. 
 
 C 5 H 13 
 
 Quintane. 
 
 C 6 H 10 
 
 Quintene. 
 
 C 5 H 8 
 
 Quintine. 
 
 ^5 H 6 C 5 H 4 C 5 H 2 - 
 
 Quintone. Quintune. 
 
 C 6 H 14 
 
 Sextane, 
 
 ^6^12 
 
 Sextene. 
 
 C 6 H 10 
 
 Sextine. 
 
 C 6 H 8 C 6 H 6 C 6 H 4 ,etc. 
 
 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 CH 2 ; and those 
 in each horizontal line, differ from each other suc- 
 cessively by H 2 . 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 ...CH 4 CnH 2 u+2 
 
 2 C 2 H 4 CnH 2 n 
 
 3 C 2 H 2 CnH 2 n— 2 
 
 4 C 5 H 6 CnH 2 n— 4 
 
 5 C 6 H 6 CnH 2 n— 6 
 
 6 C 8 H 8 CnH 2 n— 8 
 
 7 C 8 H 6 CnH 2 n— 10 
 
 8 C 10 H 8 CnH 2 n— 12 
 
 9 C 12 H 10 CnH 2 n— 14 
 
 10 C 14 H 12 CnH 2 n— 16 
 
 11 C 14 H 10 CnH 2 n— 18 
 
 12 C 17 H 14 CnH 2 n— 20 
 
 13 C 16 H 10 CnH 2 n— 22 
 
 14 C 18 H 12 CnH 2 n— 24 
 
 15. C 20 H 14 CnH 2 n— 26 
 
 16 ■ CnH 2 n— 28 
 
 17 C 22 H 14 CnH 2 n— 30 
 
 18 C 26 H 20 CnH 2 n-32 
 
 Cn means any number of carbon atoms, and 
 H 2 n+2, twice as many hydrogen atoms and 2 
 over; CnH 2 n, twice as many hydrogen atoms as 
 as carbon atoms; CnH 2 n — 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 CnH 2 n-|-2), are all saturated 
 compounds; those in the second column (series 
 CnH 2 n) are dyad radicals, capable of uniting with 
 2 atoms of chlorine without displacing hydrogen, 
 as in ethene chloride, C 2 II 4 C1 2 ; those in the third 
 column, are triads, etc. 
 
 The first members, as methane, CH 4 ; ethane, 
 C 2 H 6 ; propane, C 3 H 8 ; ethene, C 2 -H 4 ; ethine, 
 C 2 H 2 , etc., are gaseous at ordinary temperatures, 
 and increase in density in regular ratio, with each 
 additional CH 2 . 
 
 The higher members, of which C 35 H 72 is the 
 extreme, are solid ; while the intermediate mem- 
 bers, such astetrane (quartane and butane), C 4 H 10 ; 
 decane, C 10 H 22 , etc., are liquid. The boiling 
 points of the liquid hydrocarbons increase regu- 
 larly, but in diminishing ratio with each increase 
 of CH 2 . Thus: 
 
 Tetrane, C 4 H 10 , boils at 0° (32F) Increase. 
 
 Pentane, C 5 H l2 , " " 38° (100) 38 C. 
 
 Hexane, C 6 H 14 , " « 69° (156) 31 
 
 Heptane, C 7 H 16 , " " 98° (208) 29 
 
 Octane, C 8 H 18 , " " 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 H 2 0. A few of the most common 
 occurrence are subjoined: 
 
 CH 4 
 
 Methane. 
 
 CH 3 
 
 Methyl. 
 
 CH 2 " 
 
 Methene, 
 
 CH'" 
 
 Methenyl. 
 
 C 2 H 6 
 
 Ethane. 
 
 C 2 H 5 
 
 Ethyl. 
 
 C 2 H 4 " 
 
 Ethene. 
 
 C2H3'" 
 
 Ethenyl. 
 
 C 3 H 8 
 
 Propane. 
 
 C 3 H 7 
 
 Propyl. 
 
 C 3 H 6 " 
 
 Propene, 
 
 C 3 H 5 '" 
 
 Propenyl. 
 
 O«H 10 
 
 Butane. 
 
 C 4 H 9 
 
 Butyl, etc. 
 
 
 
 The final syllable yl indicates a compound radi- 
 22 
 
258 Organic Chemistry. 
 
 cal of uneven valency; so also certain radicals of 
 both uneven and even valency, not derived from 
 saturated hydrocarbons, as nitryl, N0 2 , carbonyl, 
 CO, etc. The derivation of certain other radicals 
 suggest their names ; thus from ammonia, NH 3 , by 
 abstraction of one atom of hydrogen, is derived 
 amidogen, NH 2 ; and by taking away two atoms of 
 hydrogen from NH g , is derived the dyad radical, 
 imidogen, NIL". Cyanogen (meaning blue), ON 
 (quasi symbol Cy), when free, is formulated as 
 CN"-C]Sr, analogous to the molecule of chlorine, 
 Cl-Cl, and when acted upon by a metal, as K 2 , re- 
 sults according to the equation, 
 
 K 2 + Cy 2 = 2KCy 
 
 Potassium. Cynogen. Pot. Cyanide. 
 
 Just like a molecule of chlorine on a molecule of 
 potassium, K 2 + Cl 2 , = 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, 
 aniidogeu, 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 
 
 methyl, methenyl, 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, (CH 5 ) 2 0, and 
 ethyl chloride, CH 5 C1 ; and electro-negative, in 
 metallic salts, as in lead ethide, Pb(CH 5 ) 2 . 
 
 From them, all well defined organic compounds 
 may be 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. 
 CH g ,OH C 2 H 5 ,OH C 2 H 4 (OH), C 3 H 5 (OH) 3 
 
 Methyl Alcohol. Ethyl Alcohol. Ethene Aloohol. Propenyl Alcohol. 
 
 Alcohols are really hydroxides, analogous to the 
 hydroxides of metals. Thus sodium hydroxide, 
 ]N"aOH, calcium hydroxide, Ca(OH) 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, H — — H, and consist of hydrocarbon radi- 
 cals and oxygen. Common ether is ethyl "oxide, 
 C 2 H 5 =:0 — C 2 H 5 . A mixed ether contains more 
 than one hydrocarbon radical ; methyl-ethyl 
 ether, CH, — — C 9 H K , is a mixed ether. 
 
260 Organic Chemistry. 
 
 3. Haloid Ethers, are compounds containing 
 hydrocarbon radicals, and a haloid element; chlo- 
 roform, CHClg is a haloid ether, made up of the 
 trivalent hydrocarbon radical methenyl, and three 
 atoms of univalent chlorine. 
 
 Iodoform CHI S , and "Dutch Liquid" C 2 H 4 C1 2 , 
 are also examples of haloid ethers. 
 
 4. Organic Acids, may be defined as oxygenated 
 hydrocarbon radicals and hydroxyl, as acetic acid 
 C 2 H § 0, OH, formic acid CHO, OH, lactic acid, 
 C 3 H 5 2 , 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 carboxyl COOH, graphically 0=C — — H, 
 thus acetic acid CH 3 COOH ; formic acid, H, COOH ; 
 lactic acid C 2 H 5 0, 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 2 — COOH, 
 as in succinic acid, | it is dibasic. 
 
 CH 2 — COOH, 
 
 5. Esters, are ethereal salts, formed by hydro- 
 carbon radicals, and organic or inorganic acid 
 radicals, for example ethyl acetate, C 2 H 5 , C 2 H 3 2 . 
 Ethyl alcohol and nitric acid, yield the ester, ethyl 
 nitrate, and water. 
 
 C 3 H 6 OH+HM) 3 =C 2 H 6 N0 3 +H 2 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 
 alcohol, by oxygen, all of which may be understood 
 by the empirical formulas : 
 
 C 2 H 6 + = C 2 H 4 + H 2 0. 
 
 Ethyl Alcohol. Aldehyde. 
 
 C 2 H 4 + = C 2 H 4 2 . 
 
 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. 
 
 C 2 H 3 (CH 3 )0; 
 
 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 CH 3 
 
 0=0 
 
 CH 3 . There are also 
 diethyl, and ethyl-methyl, etc., ketones. 
 
 8. Amines, are derivatives of ammonia by sub- 
 stitution of hydrogen, by hydrocarbon radicals. 
 
C 2 H 5 
 
 fC 2 H 5 
 
 2 H 6 
 
 N^C 2 H 5 
 
 H 
 
 lC 2 H 5 
 
 262 Organic Chemistry. 
 
 fC 2 H 5 
 1S{ H JS 
 
 u 
 
 Ammonia. Ethylamine. Diethylamine. Triethylamine. 
 
 The amines are numerous, and are mostly basic 
 in character. Where all the hydrogen is removed, 
 the trivalent radical N" is evidently capable of taking 
 up three univalent radicals as above, or one triva- 
 lent radical, as below : 
 
 N==CH"' N=C 2 H 3 '" 
 
 Methenyl Nitril. Ethenyl Nitril. 
 
 These trivalent nitrils are not basic ; they are all 
 neutral, except the first, which is acid, capable like 
 HC1, of exchanging its hydrogen for a metal, and 
 may therefore be regarded as composed of hydro- 
 gen and the univalent radical cyanogen, 
 NCH = HON" 
 
 Methenyl Nitril. Hydrogen Cyanide. 
 
 (Hydrocyanic Acid). 
 
 NC 2 H 3 = CH 3 CISr 
 
 Ethenyl Nitril. Methyl Cyanide. 
 
 Analogous to the amines, are the arsines, stibines, 
 and phosphines. 
 
 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. 
 
 c 2 h 3 o,ke 2 c 4 H 4 o 2 ira 
 
 Acetamide. Succim'mide. 
 
Carbon Compounds. 263 
 
 CHAPTER IV. 
 
 CARBON COMPOUNDS. 
 
 When two or more compounds can be represented 
 by the same empirical formula, they are said to be 
 isomeric. The difference in the chemical and physi- 
 cal nature of isomeric bodies, is due to the difference 
 in the relative position, or arrangement, of the 
 atoms in the molecule, and it is upon this fact that 
 the somewhat startling innovation of 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 
 
 | H-C-HH 
 
 H-C— H 
 H-g-H 
 
 H-C C-H 
 
 I I 
 
 H-C-HH 
 H— 6— H 
 
 i 
 
 Isopentane. 
 
264 Organic Chemistry. 
 
 Metamerie isomers, are those bodies which have 
 
 the same composition, but differ greatly in their 
 
 transformations under similar circumstances ; as an 
 
 example, the formula C 3 H 6 2 represents methyl 
 
 acetate, ethyl formate, and propionic acid, two of 
 
 which we subjoin graphically. 
 
 H 3 C 
 
 H 3 C H 2 
 
 i 
 
 0=C— 0— CH 3 o=C-0— H 
 
 Methyl Acetate. Propionic Acid. 
 
 Polymeric compounds are those which have the 
 same percentage composition but differ in molecu- 
 lar weight. Examples of this class are found in 
 the series, homologous with CH 2 : 
 
 Ethene (ethylene) C 2 H 4 . 
 
 Propene (propylene) C 3 H 6 . 
 
 Tetrene (bytylene) C 4 H 8 . 
 
 Pentene (amylene) C 5 H 10 . 
 
 Several essential oils are isomeric with oil of 
 turpentine, C x H 1 6 ; and others are polymeric with 
 the latter, having the formulas, C 20 H 32 C 30 H 48 , 
 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 CH 4 0. 
 The rational formula is CH 3 OH. The formula 
 C 2 H 4 N 2 0, expresses the number and kind of atoms 
 in both ammonium 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. 
 
 NH 4 CITO = (¥H 2 ) 2 CO 
 
 Ammonium. Cyanate. Carbamide (Urea). 
 
 Ammonium cyanate can be prepared from inor- 
 ganic sources. Its molecular transformation into 
 urea by Wohler marked the tirst artificial produc- 
 tion of an organic compound. 
 
 23 
 
266 Organic Chemistry. 
 
 CHAPTER V. 
 
 PARAFINS, SERIES CnH 2 n+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 : 
 
'Parqfins, etc. 267 
 
 H H H 
 
 H— 0— H H— C— H H— C— H 
 
 H H— C— H H— C— H 
 
 Methane. 
 
 H H— C— H 
 
 Ethane. 
 
 k 
 
 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, C A H 1 , it is possible to write the 
 graphic formula in at least two ways; and it is a 
 fact that two kinds of butane are recognized : 
 
 H 
 H H— C— H 
 
 H-A- 
 
 C— H 
 
 H H— C— H 
 
 A 
 
 Isobutane. 
 
 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 CH 2 ; the latter mem- 
 bers, being solid. Parafin itself is a mixture of 
 the higher members. 
 
 Methane, CH 4 , 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, CH 3 , H (methane), 
 when acted on by chlorine forms methyl chloride 
 CH 3 , CI. Ethyl hydride C 2 H 5 ,H (ethane) simi- 
 larly also forms, by losing an atom of hydrogen, 
 ethyl chloride C 2 H 5 C1, 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, CHC1 3 , results. 
 Chloroform however, is commercially prepared, by 
 distilling together, either methyl, or ethyl alcohol, 
 and bleaching powder. 
 2C 2 H 6 0+5CaCl 2 2 =2CaC0 3 +2CaCl 2 +Ca(HO) 2 +4H 2 0+ 
 
 Alcohol. 
 
 2CHC1 3 . 
 
 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 
 hydrate. It possesses strong solvent powers on the 
 different 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 
 anaesthetics, 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 a nti- spasmodic and anodyne. 
 
 Dose, 0.06-0.30 f Gm. (nt i-v). 
 
 For inhalation 4. — 8 f Gm. (fgi-ij). 
 
 Iodoform, methenyl iodide, CHI 3 , 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 off 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 sequelae. 
 
 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 
 
Parafins, 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; i. 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 2 H 2 , 
 2CHI 3 + q. s. Heat = I 6 + C 2 H 2 . 
 
 Iodoform is neither a local nor general irritant. 
 Internally exhibited, it is antiseptic, anodyne, 
 stimulant, alterative, and tonic. It is not wholly 
 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, CHBrg, 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. 
 
 * ?'■'■ 1 Br 
 
 H-C-H H-C-01 H-i-I H-i-Br 
 ^ A" 1 Br 
 
 Methane. Chloroform. i odoJorm . Brom ofL, 
 
Alcohols, etc. 273 
 
 CHAPTER VI. 
 
 ALCOHOLS, ETC. 
 
 Methyl Alcohol, CH g OH, 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. 
 
 f H 
 
 
 rcH 3 
 
 
 H 5 
 
 II 
 
 c Ih 
 
 °i H 
 
 [oh 
 
 C^ 
 
 H 
 
 H 
 
 c- 
 
 
 . 0H 
 
 
 L OH 
 
 Methyl Alcohol. 
 
 Eihy 
 
 . Alcohol. 
 
 Prop; 
 
 f] Alcohol. 
 
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 C 4 H 10 O, 
 etc., admit of three modifications, and form three 
 insomeric alcohols, primary, secondary and ter- 
 tiary. 
 
 CH 2 CH 2 CH 3 fCH 2 CH 3 fCH 3 
 
 H c ICH b JcH, 
 
 ^ H 1 CH 3 
 
 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. 
 
 c 
 
 rcH 
 
 CH 
 
 H 
 
 OH 
 
 CH, — H 2 = CH 3 — CO — CH ; 
 
 Dimethyl Ketone. 
 
 And 
 
 fCH 2 CH 
 
 c I CH 3 2 - k 2 = CH 3 - CO - C 2 H 6 
 
 1 H Minus. Methyl-ethyl Ketone. 
 
 [OH 
 
 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 
 carbou 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 : 
 
 c J CH 3 + 4 = CH 3 2 - C 3 H 6 0, + H 2 
 
 >. CH Q Formic Acid. Propionic Acid. 
 
 [oh 3 
 
 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 : 
 
270 
 
 Organic Chemistry. 
 
 o 
 t> 
 
 H 
 
 C 
 ft 
 
 ^ 
 
 ri 
 
 o 
 W 
 
 
 o 
 
 O 
 
 HJ 
 
 <! 
 
 << 
 
 ^ 
 
 
 
 ^ 
 
 g 
 
 « 
 
 P4 
 o 
 
 -i 
 
 ft 
 
 
 
 r-~< 
 
 J 
 
 H 
 
 
 « 
 
 pd 
 
 Ph 
 
 W 
 
 
 K 
 
 
 w 
 
 
 O 
 
 be . 
 
 + 
 
 Rplnw 90 cci^cccocm • aio co t- cc co 
 r^eiow -u. H ^ i- c o • o n n n n oo 
 
 O 
 
 o h ^ co n q a w -o 
 
 HHHnHHN(M01 
 
 N N """^OOOOOOOOOOO 
 
 co-pl l-rt HH H-i M t r<>fMM > * -l ~''*"*i > ^'" >~~< I - -! I-_I ■~ H 
 
 DOOOOQOOQQQOOOO r JOOOO 
 
 ■3 -| • ^ 
 
 O « .S ?* a •- "S -"S * .S - fl 
 tl i-rt s- H y s_ • -i d &D S- - ■, OJ 
 
 O.U O J 
 
 a V> £i, >> S3 ^ ^ ^ n» • 
 
 o "3 
 
 ° GO CO OS CM O Tti 
 
 S N OS O CO IC CO 
 CD , — ' i — I , — i , — I 
 
 Is 
 
 3 
 
 on oooo : :°. : :°* : : : : :°.°. 
 
 Q «) « h h h h , . »-H . . hrl Kyi Hpl 
 
 ^(-H MMWHM . . hM . . MH hU HM 
 
 hrlt-HHH^MHH-lhM . . o- . . * . . . . «- c 
 
 l-H rq eo ■* in to t- -i -i mm 
 
 OQOOQQQ • -O • -C Ow 
 
 
 S3 
 
 
Ethyl Alcohol, etc. 277 
 
 CHAPTER VII. 
 ETHYL ALCOHOL, ETC. 
 
 Ethyl Alcohol, C 2 H 5 OH, 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. 
 
 C 6 H 12 6 = 2C 2 H 6 + 2C0 2 
 
 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 pas- 
 teurizing, by heat or. by bottling, or the use of 
 chemicals. 
 
 C 2 H 6 + = C 2 H 4 + H 2 
 
 Alcohol. Aldehyde. 
 
 C 2 H 4 + = C 2 H 4 2 
 
 Aldehyde. Acetic Acid. 
 
 Acet-Aldehyde C 2 H 4 0. 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, C 2 H 3 O.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, CH 3 O.Cl; 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, C 2 H 3 O.NTI 4 . Polymers 
 of aldehyde are known, a doubling and trebling of 
 the molecule, as C 4 H 8 2 , and C 6 H 12 3 . 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, C 2 H 3 2 .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, 
 CH0 2 H ; next, acetic, and so on. With each ad- 
 dition of CH 2 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 name, 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 (C 2 H 3 2 ) 2 -j- 3 Aq. 
 The latter compound is of great value to the 
 chemist, and possesses soothing astringent medic- 
 inal properties. Calcium carbonate will dissolve in 
 acetic acid (even dilute) forming calcium acetate 
 Ca(C 2 H 3 2 ) 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, C 5 H 11 C 2 H 3 2 , has 
 the flavor of bananas; ethyl butyrate, C 2 H 5 C 4 
 H 7 2 , of pineapples, and amyl valerate, C 5 H 11 
 C 5 H 9 2 , 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 5 H 11 C 2 H 3 2 + XaOH = ]S T aC 2 H 3 2 + 
 
 Amyl Acetate. Sodium Acetate. 
 
 6,H 1 ' 1 OH 
 
 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, C 2 H 4 2 
 
 Monochloracetic acid, C 2 H 3 C10 2 
 Dichloracetic acid, C 2 H 2 C1 2 2 
 
 Trichloracetic acid, C 2 HC1 3 2 
 The aldehyde of trichloracetic acid is the liquid 
 chloral, C 2 HC1 3 0, 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. 
 
 C 2 H 6 + 8G1 = 5HC1 + C 2 HC1 3 
 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. 
 
 C 2 HC1 3 + KOH = KCH0 2 + CHC1 3 
 
 Chloral. Pot. Formate. Chloroform. 
 
 24 
 
282 Organic Chemistry. 
 
 Chloral forms with water in molecular propor- 
 tions, chloral hydrate, C 2 HC1 3 0,H 2 0, 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 pyorrhoee, 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 habit 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 Gra (gr. x). 
 
 Syrupi aurautii cort. 
 
 Aq. menth pip. aa 15.00 f Gm (fgss). 
 M. S. A hypnotic potion in acute alveolar abscess. 
 
284 Organic Chemistry. 
 
 CHAPTER VIII. 
 
 ETHERS, ETC. 
 
 Oxygen Ethers are denned as alcohols (typical), 
 with the hydroxyllic hydrogen replaced by an al- 
 cohol radical. Thus: 
 
 C2 2 5 }° c 2 M:}° 
 
 Ethyl Alcohol. Ethyl Oxide. 
 
 They may also 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. 
 
 i}'° h}<> S2}o 
 
 Sodium Hydrate. Sodium Oxide. 
 C 2 H 5 In 
 
 C 2 H 5 f° 
 
 Ethyl Alcohol. Ethyl Oxide. 
 
 Ethyl Oxide (C 2 H 5 ) 2 0, common ether, known 
 also as sulphuric ether, can be obtained from a 
 large number of ethyl compounds, as for instance : 
 
 C 2 II 5 T + C 2 H 5 
 E 
 
 = KI + 
 
 EthvJ Iodide. 
 
Ethers, etc. 285 
 
 Practically, ether is obtained from ethyl alcohol 
 by the dihydrating influence of sulphuric acid, at 
 the proper temperature : 
 2C 2 H 6 - H 2 = O 4 H 10 O for, (C 2 H 5 ) 2 0,1 
 
 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 Medic a. — 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 
 Hoffmann'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 (C 2 H 5 N0 2 ), it is an excellent diuretic 
 and diaphoretic, in fevers. 
 
286 Organic Chemistry. 
 
 The first practical use of ether as a general 
 anaesthetic was made by Dr. Morton, a dentist of 
 Boston, in 1846. 
 
 Although much slower in its immediate effects, 
 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, C 2 H 5 C1, on account of its ten- 
 dency to induce excessive cold by rapid evaporation, 
 
Ethers, etc. 287 
 
 has been employed as a local anaesthetic 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 CH 2 , and containing equivalent chlorine 
 as a substitute for hydrogen. 
 
 CH3CI CH 2 C1 2 
 
 Methyl Chloride. Mithene Chloride. 
 
 C 2 H 5 C1 C 2 H 4 C1 2 
 
 Ethyl Chloride. Ethene Chloride. 
 
 C3X1 7 C1 C 3 HgCl 2 
 
 Propyl Chloride. Propene Chloride. 
 
 The density of these haloid ethers, increase in 
 regular gradation, by each addition of CH 2 , just like 
 the typical 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, CH 3 C1, 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 2 1I 5 C1, is 
 a light liquid, the vapor of which is two and a half 
 times as heavy as air; and ethyl bromide, C 2 H 5 Br, 
 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 : 
 
 g H 4o + C 2 H 6 I = KI + CH b lo 
 
 -^ J Ethyl Iodide. P PT J 
 
 Pot. Ethylate. ^ 2 ^5 
 
 Methyl-ethyl Ether. 
 
 Methyl-ethyl ether,^ 1 ^ 1 Boils at 11°C 
 
 2 5 J 
 
 Ethyl-butyl " ^H 5 | « 8Q o 
 
 Methyl-amyl " ^^ jo " 92° 
 
 Ethyl-amyl " ^^ |o 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, C 16 H 33 OH, is characteristic of spermaceta ; 
 and melyl alcohol, C 30 H 61 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. 
 
Ethers, etc. 289 
 
 Amyl alcohol, jpentyl alcohol, C 5 H 11 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. 
 
 C II 1 
 
 Amyl acetate, p 5 ^ 1 /) > 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, C 5 H 11 1N'0 2 , 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 
 
290 Organic Chemistry. 
 
 CHAPTER IX. 
 
 OLEFINES, ETC. 
 
 The homologous hydrocarbon series CnH 2 n, next 
 isologous to the parafins, are simple multiples of 
 CH 2 . They are dyad radicals, produced by ab- 
 straction of two atoms of hydrogen from the satu- 
 rated parafins. Thus — 
 
 CH 4 - 
 
 Methane. 
 
 H 2 
 
 - CH 2 
 
 Methene, or Methylene. 
 
 2 H 6 - 
 
 Ethane. 
 
 H 2 
 
 = C 2 H 4 
 
 Ethene, or Ethylene. 
 
 « 
 
 H 2 
 
 = C 8 H 6 
 
 Propene, or Propylene. 
 
 a 
 
 H 2 
 
 — C 4 H 8 
 
 Tetrene, or Butylene. 
 
 a 
 
 H 2 
 
 = C 5 H 10 
 
 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 C 2 H 4 , forms with chlorine, 
 an oily liquid, C 2 H 4 C1 2 . 
 
 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, C 30 H 60 , are solid. 
 
defines, etc. 291 
 
 The defines maybe formed by various reactions* 
 only one of which we will mention, i. e., the ab- 
 straction of water, from corresponding monatomic 
 alcohols (methane series), by powerful dehydrating 
 agents, such as sulphuric acid, zinc chloride, or phos- 
 phoric oxide. Thus — 
 
 C,H„OH - H 2 = C 5 H 10 
 
 Amyl Alcohol. Araylene. 
 
 The alcohols of the define series are diatomic, as 
 ethylene alcohol, C 2 H 4 (OH) 2 . They are called 
 glycols because they are intermediate in the series 
 belonging to ordinary alcohol, and the series of tri- 
 atomic alcohols, of which latter glycerine, C 3 H 5 
 (OH) 3 , is the best known. 
 
 Diatomic alcohols, glycols, produce by oxidation, 
 two series of acids, monobasic and 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. 
 CH 2 OH C 2 OH COOH 
 
 CH 2 OH COOH COOH 
 
 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 : 
 
292 Organic Chemistry. 
 
 Carbonic acid, CH 2 3 
 
 Glycollic acid, C 2 H 4 3 
 
 Lactic acid, C 3 H 6 3 
 
 Butylactic acid, C 4 H 8 3 
 
 Valerolactic acid, C 5 H 10 Oj 
 And the oxalic series : 
 
 Oxalic acid, C 2 H 2 4 
 
 Malonic acid, C 3 H 4 4 
 
 Succinic acid, C 4 H 6 4 
 
 Pyrotartaric acid, C 5 H 8 4 , 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- 
 lene glycol, C 3 H 6 (OH) 2 + 2 = H 2 + C 3 H 6 3 , 
 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 
 
 CH $ — CH^XooTl4 or < I 
 
 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(CH 3 -CH < C00 )Ca. CH 3 -CH< C00Na 
 
 Calcium Lactate. Sodium Lactate. 
 
 CH 3 — CH< co g' Na 
 
 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, 
 
 CH 3 — CH< C 5 ( J H « CH 3- CH <COO,C 2 H 5 . 
 
 Ethyl Lactic Acid Monoethyl Lactate. 
 
 CH 3~ CH <cbd,c 5 2 H 5 . 
 
 Diethyl Lactate. 
 
 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. 
 
 C 6 H 10 O 5 +H 2 O = U 6 H 12 O 6 . 
 
 Starch. Glucose, Levulose, and Dextrose 
 
 ^6^12^6 = 2C 3 H 6 3 . 
 Glucose. Lactic Acid. 
 
 C 12 H 22 11 +H 2 = 40 3 H 6 3 . 
 
 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, Ca(C 3 H 5 3 ) 2 , being formed, 
 which permits a continuation of the process. 
 
 Oxalic Acid, C 2 H 2 4 , 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 2 — COOH CHOH— COOH CHOH— COOII 
 
 h 
 
 i i 
 
 H 2 — COOH CH 2 -COOH CHOH— COOII 
 
 Succinic Acid- Malic Acid Tartaric Acid. 
 
defines, 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 C0 2 , takes 
 place. 
 
 Cream of tartar, is hydrogen-potassium tartrate, 
 
 TT ^| 
 
 jt VC 4 H 4 6 ; 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 : 
 
 HNaC0 3 +HKC 4 H 4 6 =KNaC 4 H 4 6 +H 2 0+C0 2 . 
 
 Rochelle Salt. 
 
 The escaping C0 2 , 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- 
 
 cs, used more or less in medi- 
 
 mony, SbQ JC 4 H 4 ' 
 
 cine, as an emetic. 
 
 Citric acid, C 6 H 8 7 , 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 : 
 
 C 6 H 5 7 
 
 Citric Acid. 
 
 Klc 6 H 5 7 
 
 Dipotassium. 
 Citrate. 
 
 C 6 H 5 7 
 
 K 
 H 
 
 Monopotassium. 
 Citrate. 
 
 |jc 6 H 5 7 
 
 Tripotassium. 
 Citrate. 
 
Fatty Acids, 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 palmitic, margaric and stearic 
 belong to the group of monobasic fatty acids. Pal- 
 mitic acid, C 16 H 32 2 , 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 17 H 34 2 , is in- 
 termediate between palmitic and stearic acids. The 
 latter acid, C 18 H 36 0, 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, C 18 H g4 2 , is monabasic, but belongs 
 to another series of acids, having the general 
 formula, CnH 2 n — 2 2 . It is the 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 3 H 6 " ; . 
 
 Glycerine, Glycerol, is propenyl alcohol, and as 
 propenyl, is a triad radical, the alcohol in question 
 must be triatomic. 
 
 C 3 H 5 '" 
 
 With some monobasic acids, therefore, this alco- 
 hol may form three distinct ethers, as with acetic 
 acid : 
 
 C 2 H 3 2 rC 2 H 3 2 ^C 2 H 3 2 
 
 CoHr "< OH CoHrK C Hq0 CoHr < C 9 H o O o 
 
 OH (OH (C 2 H 3 2 
 
 The natural oils and fats are generally found as 
 triple (normal) ethers of palmitic, margaric, stearic 
 and oleic acids : 
 
 (C 16 H 31 2 rc 17 H 33 2 
 
 C 3 H 5^ C 16 H 31 2 C 3 H 5^ ^17 H 33 2 
 
 1 C 16 H 31 2 l C 17- H 33 2 
 
 Palmitin. Margarine. 
 
 [^18^35^2 (C l8 H 33 2 
 
 C 3 H 5 < C 18 H 35 2 C 3 H 5 < C 18 H 3 30 2 
 
 (.C 18 H 35 2 1^18H3 S 2 
 
 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 
 
 C 3 H 5 (C 18 H 35 2 ) 3 + 3K0H = 3KC 18 H 35 2 + C 3 H 5 (0H) 3 
 Propenyl Stearate. Pot. Stearate. Prepenyl Alcohol. 
 
 (Ste'arin). (Soap). (Glycerine). 
 
 Glycerine is also produced in small quantity in 
 sugar fermentation, and is now separated largely 
 from the fats, by high pressure steam. 
 
 When acted on by dilute nitric acid, glycerine 
 
 exchanges 2 atoms of hydrogen for 0, forming 
 
 glyceric acid. 
 
 CH 2 OH 
 
 i 
 
 HOH 
 
 COOH 
 
 When treated with strong nitric and sulphuric 
 acids, glycerine yields the explosive compound 
 known as nitro-glycerine, C 3 H 5 (JS0 3 ) 3 . This pro- 
 penyl-nitrate is a thick oily liquid ; it burns quietly, 
 but if struck fiercely or ignited by a fulminate, it 
 explodes with 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 liquid 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. 
 
300 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, C 3 -H 4 0, 
 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. (31J) 
 
 Glycerina, . 30.00 fGm. (fgi) 
 Acidi Carbolici, 8.00 fGm. (feij) 
 
 Glycerina, . 30.00 fGm. (fgi) 
 Sodii Biboras, . 8.00 Gm. (gij) 
 
 The univalent radical allyl, C 3 H 5 , 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— C— H 
 H-C— H 
 
 H— C— H 
 
 II 
 C-H 
 
 1 
 
 H— C— H 
 
 Glycerol. 
 
 H— C— H 
 
 1 
 H 
 
 Allyl Alcohol. 
 
 301 
 
 The natural oil of garlic owes its pungency to 
 allyl sulphide (C 3 H 5 ) 2 S ; the oil of mustard, to allyl 
 sulphocyanate, C 3 H 5 CNS. 
 
302 Organic Chemistry. 
 
 CHAPTER XL 
 AMYLENE, ETC. 
 
 We have alluded to the olefin es, dyad hydrocar- 
 bons of the general formula, CnH 2 n, and stated 
 that one source of their derivation is by dehydrat- 
 ing the alcohol of the same number of carbon 
 atoms. Thus, isopentene (amylene), C 5 H I0 , is ob- 
 tained by action of dehydrating agents, such as 
 sulphuric acid, zinc chloride, phosphoric oxide, 
 etc., on pentyl (amyl) alcohol, 
 
 CsHiiOH — H 2 = C 5 H i0 . 
 
 The formula, C 5 H i0 , is capable of four modifi- 
 cations. Wormed pentene, sometimes regarded as 
 ethyl-allyl, C 2 H 5 ,C 3 H 6 , 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 6 H i0 are repre- 
 sented below : 
 
Amylene, etc. 303 
 
 1st. CH 3 — CH a — CH 2 — CH = CH 2 
 
 Normal Pentene. 
 
 2d. qh 3 >CH — CH = CH 2 
 
 Isopentene. 
 
 3d. CH 3 — CH 2 — CH = CH — CH 3 . 
 4th. Qg 3 >C = CH — CH 3 
 
 Pental. 
 
 Pental is said to be produced from amylene hy- 
 drate (amylene 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 5 H u OH C 6 H I0 }oH 
 
 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 anaesthetic 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 Nevertheless, pental has not been re- 
 ceived thus far with as much favor as its friends 
 think it deserves. 
 
 The series of hydrocarbons, CnH 2 n — 2, of which 
 Ethine (acetylene), C 2 H 2 , 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 CH 2 . 
 
 Acetylene, C 2 H 2 , 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- 
 
Amylene, etc. 305 
 
 guished as 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 = C 2 H 2 . 
 
 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 2 H 4 , C 2 H 2 -f H 2 = C 2 H 4 . 
 
 Ethylene combines with concentrated sulphuric 
 acid to form basic ethyl-sulphate, C 2 H 4 + H 2 S0 4 
 == H, C 2 H 5 S0 4 , and this, when heated with caustic 
 potash, yields as follows : 
 H, C 2 H 5 S0 4 + 2KOH = C 2 H 6 + H 2 + K 2 S0 4 
 
 Alcohol. 
 
 In ethane, C 2 H 6 , the 2 carbon atoms are united by 
 1 bond, in ethene (ethylene (C 2 H 4 ), the carbon atoms 
 are united by 2 bonds, and in ethine (acetylene) the 
 carbon atoms are united by 3 bonds, thus : 
 H 
 
 I 
 H— C— H 
 
 H— C— H H— C—H C— H 
 
 k 
 
 H— C— H C— H 
 
 Ethane. Ethene. Ethine. 
 
 The hydrocarbons of the general formula, Cn 
 26 
 
306 Organic Chemistry. 
 
 H 2 n — 6, are represented by the first member of the 
 series, Benzene, C 6 H 6 , (not the petroleum product, 
 Benzine); the second member Toluene, C 7 H 8 , 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, 6 H 6 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. 307 
 
 — c— q— H— C— C— H 
 
 // X // \ 
 
 -C C— H-C C— H 
 
 — C=C— H— fcC— H 
 
 Benzene Ring. Benzene. 
 
 H— C C— CH S 
 
 H— C=C— H 
 
 Methyl Benzene. 
 (Hat-rack). | (Toluene). 
 
 Groups of compound radicals like CH 3 attached 
 to the nucleus ring, in the place of H, form lateral 
 chains, which themselves may give up H, to form 
 substitution derivatives. 
 
 The homologues of benzene, as toluene, etc., 
 (C 6 H 6 + CH 2 , etc.), may be derived by substitution 
 of methyl, CH 3 , for one or more of the six hydro- 
 gen atoms ; and where but one hydrogen atom is 
 removed from benzene, the compound radical phenyl, 
 C 5 H 5 , 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, C 8 H 8 , naphthalene, C 10 H 8 , and anthracene, 
 C l4 H 10 , and the terpenes, C 10 H 16 . 
 
 Phenyl alcohol,C 6 H 5 0^1, 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— O— 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 
 C 6 H 5 OK, by giving up its hydroxy lie hydrogen to 
 the metal. This reaction however suggests an 
 alcohol, and moreover, carbolic acid forms, like 
 the alcohols, compound ethers, such as methyl 
 phenate C 6 H 5 — — CH 3 , {anisol), and ethyl phe- 
 nate C 6 H 5 =0— C 2 H 5 , (phenetol), etc. 
 
 Materia Medica. — Phenyl alcohol, carbolic acid, 
 phenic acid, simply phenol, "when 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 Gm. (grj) in solution, or pill. 
 
 Antidotes, olive oil and saccharated lime. 
 
 Robinson'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. 
 
 R. Acida carbolici, 2.00 Gin. (gss) 
 Glycerini, . 10.00 fGm. (feijss) 
 
 Aq. Kosajq. s. ad., 120.00 fGm. (fgiv) 
 M. S. Antiseptic solution. 
 
 Creasote is a product of the distillation of 
 wood tar, and is a mixture of several phenols, 
 such as carbolic acid, creasol, C 8 H 10 O 2 , and cre- 
 sylol, C 7 H 8 0. These latter may also be attached 
 to the benzene hat-rack: 
 
310 Organic Chemistry. 
 
 CH 3 -C— C— CH 3 H— C— C-CH-. 
 
 H-<5 .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, anesthetic, 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. (Xj-ij) 
 Antidotes, same as carbolic acid. 
 
Benzene Group. 311 
 
 CHAPTER XII. 
 
 BENZENE GEOUP. 
 
 The aromatic alcohols of the benzene homologues, 
 are formed by substitution of OH for H in the lat- 
 eral chains, and contain the group CH 2 0H. As, 
 
 H— C— C— H H— C— C— H 
 
 - // \ // \ 
 
 H— C C— CH 8 H— C C— CH 2 OH 
 
 \ / \ / 
 
 H— C=0— H H— C=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, C 6 H 5 COOH, is characteristic of 
 the urine of herbivorous animals. It exists already 
 formed in certain balsams and gum resins, as in 
 gum-benzoin, 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 
 
312 Organic Chemistry. 
 
 salts called benzoates are generally soluble in water 
 and have the formula, MC 7 H 5 2 . - 
 
 Calcium benzoate is changed by dry distillation 
 into calcium carbonate and benzone, or the ketone 
 of benzoic acid. 
 
 Ca(C 7 H 6 2 ) 2 = CaC0 3 + C,H 5 -CO-C e H,. 
 
 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 Wash.'" 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, NH 4 C 7 H 5 2 ,is 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. 
 
 OH 
 Salicylic acid, C 6 ^4<poOH occurs xn salicin, of 
 
Benzene Group. 313 
 
 the willow and poplar, and free, in the flowers of 
 meadow-sweet; and as mythylie ether, in oil of 
 wintergreen (Gaulheria jprocumbens), 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 
 sodii phosphas, increase its solubility. It is affec- 
 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 G-m. (gr. viij-xx.) 
 
 Gallic Acid, dioxysalicylic acid, trioxybenzoic 
 
 acid, C 7 H 6 5 , may be also erected on the benzene 
 
 ring. 
 
 27 - r 
 
314 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 14 H 10 O 9 = O C 6 H 2 =(OH) 3 
 
 CO-C 6 H 2 ==(OH) 2 
 
 \jOOH 
 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 
 tinctorial. The galls are irregularly rounded and 
 tuberculated nuts, from J to f 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 
 in water, glycerine, alcohol, and ether. It produces 
 coagula with gelatine and albumen, and 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 effectually arrest the hemorrhage, by 
 its astringent action on the vessels, and by its coag- 
 ulating effect on the albumen of the escaping blood. 
 
 Internally, tannin combinations, are frequently 
 exhibited in diarrhoea, cholera, and hemorrhage. 
 
 Dose 0.06-0.18 Gm. (gr.j-iij.) 
 
 R. Acidi Tannici 4.00 Gm. (31), 
 Glycerin*. 
 Aqua Dest. aa 15.00 fGm (f^ss). 
 
 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 quercns 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. 
 C 14 H 10 O 9+ H 2 O=2C 7 H 6 O 5 . 
 
 Tannin. Gallic Acid. 
 
 Nitro-benzene, C 6 H 5 jN0 2 , 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 phenylamine, C 6 H 5 NH 2 , 
 also known as amidobenzene, or aniline. 
 
 C 6 H 5 N0 2 +6H = 2H 2 0+C 6 H 5 NH 2 . 
 
 Nitre-benzine. 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 is the* 
 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, C 6 H 2 Vyo •' is also known as 
 
 picric acid. The picrates are highly explosive salts. 
 Many derivatives of benzene are used in medi- 
 
Benzene Group. 317 
 
 cine, such as salol, a compound of salicylic acid and 
 phenol; phenacetine, and the analogous com- 
 pound, acetanilide, C 6 H 5 — NH — C 2 H 3 2 ; resor- 
 cin, C 6 H 4 (OH) 2 ; pyridine, C 6 H 5 N; naphthaline, 
 C 10 H 8 = H H 
 
 I I 
 
 /V\ 
 
 H— C C C— H 
 
 I II I 
 
 H— c c :c— H 
 c c 
 
 i k 
 
 formulated by 
 over lapping of two benzine rings; quinicine, 
 C 9 H 9 N 2 , to which antipyrine, C 11 H 12 N 2 0, is re- 
 lated, etc. 
 
 They are antiseptic, antipyretic, and analgesic ; 
 and alone r 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 in the proportion to form water, 
 united to carbon. They include starch, woody fiber, 
 and sugars. 
 
 Starch, C 6 H 10 O 5 , 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 : 
 
 • 6C0 2 + 5H 2 = C 6 H 10 O 5 +.O ia 
 
 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 (C 6 H 10 O 5 ) 2 . 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 aud 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, C 6 H 10 O 5 , is the chief constituent of 
 vegetable fiber. 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, C 6 H 7 (N0 2 ) 3 5 , is produced. 
 Guncotton is highly explosive. 
 
 Celluloid consists of pyroxylin mixed with cam- 
 phor, 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 film, 
 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, C i2 H 22 11 , and in- 
 clude cane and beet sugar (sucrose), milk sugar 
 (lactose), and a variety of starch sugar (mal- 
 tose), etc. 
 
 Glucoses, C 6 H 12 6 , include grape sugar (dex- 
 trose), and 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 w r ater. When heated it 
 loses part of its aqueous elements, and is converted 
 into caramel. 
 
 Grape sugar (Glucose) exists in many sweet 
 fruits, and in 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 10 H 16 , are homologous with pen- 
 tone, C 5 H 6 , having the general formula CnH 2 n — 4 ; 
 and areisologous with decane, C 10 H 22 . 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 10 H 16 , 
 and are regarded as tetrad radicals ; although ap- 
 parently satisfied, they are capable of taking up 
 two molecules of HC1. If the molecule, C 10 H 16 , 
 be doubled, the polymer, C 20 H 32 , 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 Terebinthinoe, C 10 H 16 , 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 pine. 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, C 19 H 29 COOH. 
 
 Other resins, such as shellac, copal, sandara.c, 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- 
 peutine, 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 the 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 C 10 H 14 O 4 , a highly oxidized hydro- 
 carbon, which with moisture, and summer-heat, 
 developes nascent oxygen. 
 
 C 10 H 14 O 4 +2H 2 O = H 2 O 2 +C 10 H 16 O 4 . 
 
 Oxygenated Hydrogen Camphoric 
 
 Terpene. Dioxide. Acid. 
 
324 Organic Chemistry. 
 
 Materia Mebica. — Although many of the essen- 
 tial oils (especially that of cloves), have been, 
 from time immemorial, favorite domestic remedies 
 against toothache; and in practice, as ingredients 
 of pulp cap-pings, 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, C i0 H i6 , and an oxygen 
 oil, eugenol, or eugenic acid, C 9 H 1;[ COOH. 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 effectually 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 sequelse. 
 
 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. (ttl ij-v) 
 
 Oil of Sassafras is obtained oy distilling the 
 bark and wood of the root of the sassafras offici- 
 nales, 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. (ttl j-iv) 
 
 Oil of Cinnamon, oleum cinnimomi, is obtained 
 from the inner bark of the shoots of the cinnimo- 
 muw, zeylanicum (cassia), trees of the natural order 
 Lauraceae, 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, 
 C 6 H 5 - 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. (n^ g-v) 
 
Terpenes, 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 CH 3 C 7 H 5 3 . 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. (m, 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, 
 C io H i6> q/m«we, 
 
 C 10 H 14 =(C 6 H 4 <g|3_ C H 2 ^CH 3 -) 
 
 2 
 
 and eucalyptol, C I0 H i5 (OH). It exhibits a destruc- 
 tive influence on microbic forms of animal and 
 vegetable life. 
 
 Alone or combined with other antiseptics, it is 
 effective 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 fQ-m. (n\,v-xxx.) 
 
 Dose of tincture 2.00-8.00 fGm. (fSss-ij.) 
 
 B. Olei eucalypti. 
 
 Acidi carbolici aa 6.00 fGm. (fejss.) 
 
 Olei Gaultheria 2.00 fGm. (fees.) 
 M. S. Apply by syringe, in pyorrhoea (Dr. G. V. Black, 
 from Gorgas.) 
 
 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 i0 H 16 , and the ten carbon 
 phenol, carvol, C i0 H i3 OH. 
 
 Dose of the oil 0.06-0.30 fGm. (mj-v.j 
 
 Carvacrol, C 10 H 13 OH, 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 1 H 1 3 (OH), is isomeric with carvacrol. 
 It is a constituent of the volatile oil of the garden 
 plant, Thymus vulgaris, and of several other 
 plants. The isomeric relation of thymol, to carva- 
 crol, may be most easily understood by the benzene 
 hat-rack, 
 
 CH 3 . CH 3 
 
 I I 
 
 H— C C— OH H— CT C— H 
 
 I II I II 
 
 H-C C— H H— a C-OH 
 
 Carvacrol. Thymol. 
 
 Both are methyl-propyl-phenols. In carvacrol the 
 28 
 
330 Organic Chemistry. 
 
 methyl group (CH 3 ) stands to the hydroxyl group 
 (OH) in the or^Ao-position, and in thymol, in the 
 mefa -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, C 10 H 13 (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 hydroxyllic H, plus I, and may 
 be chemically known as thymol iodroxide. 
 
 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 
 
Terrenes, 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 XVI. 
 
 TERPENES, PHENOLS, ETC.— (Continued.) 
 
 Resorcin, C 6 H 4 (OH) 2 , as maybe 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 piperita, ob- 
 tained by distilling the fresh leaves of the plant. 
 It consists of a terpene and a mon atomic alcohol, 
 the latter called menthol, C 10 H i9 (OH) ; also known 
 as peppermint camphor. 
 
Terpenes, Phenols, etc. 333 
 
 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 terpen es, isomeric or polymeric, with oil of 
 turpentine (C l0 H i6 ). 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 (Hg 2 S), 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 insoluble in water, and 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. 
 
 Naphthaline, C 10 H 8 , 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 10 H 7 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. 
 
Resins, 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 
 Northern 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 astringent 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) 
 
 R. Aluminis, .... 4.00 Gm. (#) 
 
 Tincture Myrrhs, . . 8.00 fGm. (ftij) 
 Infusi Rosse comp. . . 160.00 fGm. (f§v) 
 
 M. S. Use as a gargle. 
 
 (Modified from Farquharson.) 
 
 Camphor, C 10 H 16 O, common camphor, (like other 
 camphors, such as caryophillin, C 20 II 32 O 2 ), may 
 be regarded as an oxygenated terpene. Closely re- 
 
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 10 H 17 OII, and its 
 homologue, patchouli camphor, C 1 5 H 2 7 OH, menthol, 
 or mint camphor, C 10 H 19 OH, absinthol, C 10 H I5 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 compounds, of which camphoric 
 acid, C 8 H 14 (COOH) 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 formulas, thus : 
 
 CH 3 CH 3 
 
 I I 
 
 c .a h 
 
 H— C C=C=0 H— C C— O— H 
 
 L 
 
 H 2 =C C=H 2 H 2 =C C=H 2 
 
 C-H C-H 
 
 I I 
 
 C 3 H 7 C 3 H 7 
 
 Camphor. Borneol. 
 
Hesins, Camphors, etc. 337 
 
 CH 3 
 
 ii— a c-o 
 
 .4 
 
 H 2 =C C— 
 
 \ / \ 
 C-II OH 
 
 I 
 C 3 H 7 
 
 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. Combined with chloral, or in 
 strong solution with chloroform, it is an effective 
 local anaesthetic, and is used as such in obtunding 
 29 
 
338 Organic Chemistry. 
 
 sensitive dentine, exposed dental nerve, 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 Gm. (3iv) 
 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. 839 
 
 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 filling 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 effect 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 Gm. (gr. v-xv.) 
 
 Calendula, the fresh flowering garden marigold, 
 furnishes a tincture which possesses a stimulant 
 
840 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. 
 
Alkaloids. 341 
 
 CHAPTER XVIII. 
 NATURAL ALKALOIDS. 
 
 Alkaloids are organic bases capable of uniting 
 witb acids to form salts. Many of them exist in 
 union with characteristic acids, in certain vegetable 
 products ; they also occur in animal bodies, as 
 leuco'maines ; and as a result of putrefaction, as 
 ptomaines. They are mostly poisons, are closely 
 related to the artificial amines, and contain IS" as an 
 essential element. 
 
 Those that are made up of C, H, and E", as 
 nicotine, C 10 H 14 N 2 , etc., are generally volatile 
 liquids ; while those which also contain 0, as 
 Caffeine, C 8 H N 4 O 2 , Morphine, C 17 H 19 N0 3 , 
 etc., are non-volatile solids. 
 
 Their 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. 
 
 (KH 3 ) 2 + H 2 S0 4 = (NH 4 ) 2 S0 4 . 
 
 Ammonia. Am. Sulphate. 
 
 C 17 H 19 N0 3 .+ H 2 S0 4 = C 17 H 19 M) 8 H 2 S0 4 . 
 
 Morphia. Morph, Sulphate. 
 
 Zn + H 2 S0 4 = ZnS0 4 + H a . 
 
 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, C 20 H 24 N 2 O 2 ,3fI 2 O, 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 sufiicient 
 representatives of the entire genus. 
 
 1. C. Calisaya, C. Flava, yellow bark. 
 
 2. C. 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 quinie, 
 (monobasic pentatomic) acid, C 6 H 7 (OH) 4 COOH. 
 
 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, (C 20 H 24 N 2 O 2 ) 2 , H 2 S0 4 ,3H 2 0, 
 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 
 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 Quiuia sulphatis, 1.00 Gm. (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, C 17 H t9 }sr03, 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, C 6 H 3 5 COOH. The favorite salt of mor- 
 phine, is the sulphate, (C 17 H 19 N0 3 ) 2 , H 2 S0 4 5H 2 0, 
 soluble in water and alcohol, but not in chloroform 
 or ether. Consists of white 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 effect ; and sleep ensues, induced by cerebral 
 anemia. Awakening is accompanied by headache, 
 digestive disturbance, and (with opium)constipation. 
 Subcutaneous injection of, 
 Morphia 0.01 Gm. (gr.f ) 
 Aqua Dest. 1.00 fGm. (m,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.-J-fc.) 
 Dose of Opium, 0.06 Gm. (gr. j.) 
 Dose of Tinctura opii, 1.00 fGm. (ni^xv.) 
 Dose of Tinctura opii et camphorata, 4.00 fGm. (fgi.) 
 Cocaine, is obtained from the leaves oiErythroxy- 
 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, C 17 H 21 N0 4 . It 
 forms with acids, neutral 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 anaesthesia 
 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, C 17 H 19 N"0 4 , HC1 2 H 2 0, 
 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. (rn,x) 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 ^Etheris) 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 confiding 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. f-j). 
 
Alkaloids, etc. 349 
 
 B. Cocaina Hydrochloris 1.00 Gra. (gr. xv). 
 Atropia Sulphas 0.0 1 Gm. (gr. £). 
 Arid! Carbolici (cryst.) 0.25 Gm. (gr. iv). 
 Chloral Hydratis 0*20 Gm. (gr. iij). 
 Aqua Dest. Ad. 32.00 fGm. (f|i). 
 
 M. For extraction of tooth, inject 1.00 fGm. (n^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. (f&i). 
 Aqua Dest. 6.00 fGm. (fgjss). 
 
 M. Six (6) Injections. 
 
 R. 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, Chloroformi 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, C g gH^NO-L 2 , 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 radieis 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 employment should be 
 avoided in cases of suspected cardiac weakness. 
 
 Antidotes : Emetic, animal charcoal pulv. Tannin, hot 
 alcoholic stimulants, and digitalis ; also, amyl nitrite. 
 
 Dose, tincture of the root, 0.06-0.30 fGm. (Xj-v) 
 " Aconitine, . . . 0.001 Gm. (gr. ^) 
 
 Atropine, C i 7 H 23 N~0 3 , * s the active medicinal 
 principle of the root and leaves of atropa belladonna, 
 or deadly nightshade, a perennial herbaceous plant, 
 natural to the mountainous regions of Southern 
 Europe and Asia, but now cultivated in this coun- 
 try and elsewhere. 
 
 Atropine Sulphate (C i7 H 2 3N03) 2 H 2 S0 4 ,ismuch 
 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 motor-oculi nerve, which sup- 
 plies the sphincter muscular filaments of the iris, 
 allowing the sympathetic, 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. ^.) 
 
 Dose, Fluid Extract of root 0.06-0.30 fGm. <Xj-v.) 
 
 R. Extractum Bellad. fluidum Bad. 
 
 Tinctura Aconiti Badicis aa 8.00 fGm. (gij.) 
 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 Stramonium, 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 of jimson leaves, is very efficacious 
 in reducing the pain and swelling, in acute alveolar 
 absjcess. 
 
 Cannabin, is the most active principle of cannabis 
 sativa or Hemp, (Cannabis Indica and C. Americana). 
 
 Cannabis sativa must not.be confounded with 
 Apocynum Cannabinum " 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 Tinctura Cannabis Indica. 
 (Dose, 2.00-4.00 fGm. (n^xxx-lxj 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. (ng-lx.) 
 
 R. Extractum Hamaraelidis Fluidum 4.00 fGm. (fej.) 
 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, a Synthetic " (better, Artificial), 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 yellow 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 
 
 Calcium phosphate 
 
 Calcium carbonate 
 
 Magnesium phosphate 
 
 Sodium carbonate aud chloride 
 
 (Fremy). 
 
 28.0 
 
 64.4 
 
 5.3 
 
 1.0 
 
 1.3 
 
 100.0 
 
 
 Ash. 
 
 Calcium Phos. 
 
 Mag. Phos. 
 
 Cal. Carb. 
 
 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 Mitchell's Chemistry.'] 
 
I 
 
 General Index, 
 
 357 
 
 GENERAL INDEX. 
 
 PAGE. 
 
 ..''.88 
 
 .. 279 
 .. 197 
 . 199 
 . 311 
 
 Acids 
 
 Acid Acetic 
 
 Arsenic 
 
 Arsenous 
 
 Benzoic 
 
 Boric 96 
 
 Butyric 273 
 
 Butylactic 292 
 
 Carbonic 93 
 
 Carbolic 307 
 
 Chromic 212 
 
 Cinnamie 326 
 
 Campboric 323-336 
 
 Citric 296 
 
 Eugenic 324 
 
 Formic 275 
 
 Gallic 313 
 
 Glacial Acetic 279 
 
 Glyceric 298 
 
 Glycollic 291 
 
 Hydrocbloric 55 
 
 Lactic 292 
 
 Malic 295 
 
 Maloric 292 
 
 Margaric 297 
 
 Metaphosphoric 83 
 
 Molybdic. 208 
 
 Nitric 67 
 
 Nitro-hydrocbloric 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 
 
 Sulfurous 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 
 
 Aldebyds 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 
 
858 
 
 General Index. 
 
 PAGE. 
 
 Amidogen. 258 
 
 Amylene 291-302 
 
 Amyl Acetate 289 
 
 Amyl Alcohol 289 
 
 Amyl Nitrate 289 
 
 Analysis 30 
 
 Anaesthetics 71 
 
 Anisol 308 
 
 Anilin 316 
 
 Antimony 202 
 
 Acids 203 
 
 Oxids 203 
 
 Oxysulfid 204 
 
 Antimonous chlorid 204 
 
 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 
 
 PAGB. 
 
 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 
 
 Oxychlorid 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 
 
 Caffein 341 
 
 Calcium. 143 
 
 Benzoate 312 
 
 Carbonate 144-147 
 
 Chlorid 143 
 
 Fluorid 146 
 
 Hydrate 143 
 
 Lactate 293 
 
 Oxid 113 
 
 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-Hydrates. 318 
 
 Carbomid 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 
 
360 
 
 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 
 
 Iodid 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 31y 
 
 Gun-cotton 319 
 
 Powder 134 
 
 Gutta-percha. 333 
 
 Haemostatic 18S 
 
 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 
 
 lmidogen 253 
 
 Indium 181 
 
 India Rubber 333 
 
 Ink 188 
 
 Iodin 60 
 
 Iodoform 270 
 
 Iridium. ... 223 
 
 Iron 183 
 
 By Hydrogen 187 
 
 Iron, Cast 184 
 
 Dyalized 187 
 
 Malleable 184 
 
 Pig 184 
 
 Wrought 184 
 
 Isobutane 267 
 
 Isomerism 263 
 
 Optical 264 
 
 Isomorphous 105 
 
 Isopentene 302 
 
 Isologous Series 254 
 
 Kaolin 179 
 
 Ketones 261-274 
 
 Labaraques Solution 140 
 
 Lactic Acid ' 292 
 
 Latin A bbreviations 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 
 
 Reflection 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 
 
 Malonic 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 Mediea 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 
 
 Nebula? 242 
 
362 
 
 General Index. 
 
 PAGE. 
 
 Nickel 195 
 
 Compounds 196 
 
 Nicotin , 341 
 
 Niobium 207 
 
 Nitrogen 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 327 
 
 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 
 
 Parafins 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 Cassius 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 134-136 
 
 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 
 
 Sodse Chloratse 140 
 
 Sodium 138 
 
 Arsenite 199 
 
 Compounds 138-141 
 
 Bismuthate 207 
 
 Lactate 293 
 
 Tungstate 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. 
 
 Wa ter „ 50 
 
 Glass. 90 
 
 Weights, Measures 123 
 
 Wet Method 2 16 
 
 White Lead 169 
 
 Witch-Hazel 354 
 
 Wolfram.. 208 
 
 Yttrium 148 
 
 PAGE. 
 
 Zinc 160 
 
 Cblorid igl 
 
 0x id 161 
 
 Oxychlorid 152 
 
 Oxy-phosphate 162 
 
 Sulfate 163 
 
 Zirconium 174 
 

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