LIBRARY OF CONGRESS, 
 
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 Shelf..- E.lUo^ /r 
 
 UNITED STATES OF AMERICA. 
 
■ 
 
A SYNOPSIS 
 
 OF 
 
 JY^edical (jiemistry. 
 
 A Brief Suggestive Consideration of the Practical 
 
 Facts in Theoretical, Inorganic and Organic 
 
 Chemistry, and in the Analysis of Poisons, 
 
 with a Full Consideration of the 
 
 Qualitative Analysis of Human 
 
 and Animal Urine. 
 
 FINLEY ELLINGWOOD, M. D. 
 
 Professor of Medical Chemistry and Demonstrator of Analytical Chemistry in the 
 
 Bennett Medical College: Professor and Demonstrator of Chemistry in the 
 
 Chicago Veterinary College ; Editor of the Chicago Medical Times; 
 
 Etc., Etc. 
 
 CHICAGO. 
 J. M. W. JONES STATIONERY & PRINTING CC 
 76, 78, 80 AND 82 SHERMAN STREET, 
 
Entered According to Act of Congress, in the Year 1889, by 
 
 FINLEY ELLINGWOOD, 
 
 In the office of the Librarian of Congress, at Washington, D. C. 
 
PREFACE' 
 
 During the past few years of my experience as a lecturer 
 on Medical Chemistry, I have appreciated the difficulty exper- 
 ienced by the larger proportion of medical students in obtain- 
 ing, in the short time allotted to the study, from the mass 
 of chemical literature of the day, the essential facts which will 
 make the study of Medical Chemistry of practical value to them. 
 Because of this difficulty, the entire subject is not understood, 
 and many students leave College Tcnoiving nothing about Medical 
 Chemistry. I believe that a little well learned and thoroughly 
 comprehended, will be of infinitely greater practical value than 
 the entire subject gone over and nothing understood. 
 
 With this in mind, I have endeavored to arrange, in a sim- 
 ple manner, devoid of technicalities, for my own classes, the 
 essential facts, in a concise, compact form, in the order followed 
 in my lectures, in which each topic is fully considered. The 
 blank page is intended for the entry of notes by the student, 
 in the course of the lectures, which shall assist his more perfect 
 comprehension of the subject. 
 
 I acknowledge my indebtedness to the literature of the 
 present time, and especially to the following authors : Witt- 
 haus, Fowne, Attfield, Barker, Bartley, Hoffmann and Ultz- 
 mann, Draper, Harley, Lloyd, Clowes, "Wolff, Tyson, Worm- 
 ley, etc. 
 
 If other than my own students shall see any practical 
 value in the arrangement I have here made, and can by this 
 assistance the more easily comprehend this difficult subject, I 
 shall be fully repaid. 
 
 FlNLEY ELLINGWOOD. 
 Chicago, October 1st, 1889. 
 
THEORETICAL CHEMISTRY. 
 
 Chapter I. 
 
 Science is a classified knowledge of nature, and is 
 divided into two classes — natural science and physical 
 science. 
 
 Natural Science treats of the general structure and 
 external appearance of nature. 
 
 Physical Science treats of the properties and com- 
 position of all matter. 
 
 Chemistry is that branch of physical science which 
 treats of the ultimate or atomic composition of bodies. 
 
 Matter is anything cognizable by our physical senses. 
 
 Physics and Chemistry both treat of the composi- 
 tion of matter, but physics considers matter in the 
 gross without recognizing changes which alter the abso- 
 lute character of matter, while chemistry studies the 
 most minute composition of matter, the character of its 
 ultimate constituents and all the possible changes to 
 which it may be subjected. 
 
 Inorganic Chemistry studies the composition of 
 inorganic or unorganized bodies. 
 
 Organic Chemistry studies the composition of organ- 
 ized bodies and their products. (Strictly, but illogically, 
 it is the study of those substances containing carbon.) 
 
 In the Study of Matter we will consider its divi- 
 sions, attractions, indestructibility, weight and general 
 states. 
 
 Chemistry recognizes three divisions of matter — 
 the mass, the molecule and the atom. 
 
 The Mass is any portion of matter which may be 
 appreciated by the senses. 
 
 The Molecule is the smallest particle into which 
 compound matter can be divided. 
 
 The Atom is an ultimate particle of matter, the 
 smallest subdivision possible. 
 
Two or more atoms compose a molecule, and any 
 number of molecules make up a mass of matter. 
 
 The Attractions of Matter are the forces which 
 control all matter. These are gravitation, coJiesion and 
 adhesion, and chemism. 
 
 Gravitation is the law of attraction of masses of 
 matter. 
 
 Cohesion holds the molecules of a mass together 
 when the molecules are alike, and adhesion when they 
 are unlike. 
 
 Chemism holds atoms together to form molecules. 
 
 Matter is Indestructible. It changes its form, 
 but the original constituents never change. 
 
 Weight is the measurement of the force by which a 
 body is attracted toward the center of the gravity of 
 the earth. 
 
 In chemistry, we consider three kinds of weight — 
 absolute, apparent and specific weight. 
 
 Absolute Weight is the weight of a substance 
 unaffected by the atmosphere, the entire apparatus being 
 in a vacuum. 
 
 Apparent Weight is the usual weight, as deter- 
 mined in the atmosphere by scales. 
 
 Specific Weight or specific gravity is the com- 
 parison of the weight of a given bulk of a substance 
 with an equal bulk of some substance accepted as the 
 standard of comparison. 
 
 The General States in which matter may exist 
 are three — solid, liquid and gas. 
 
 In the solid form the cohesion between the molecules 
 of matter is great, and the mass can be separated only 
 with violence. 
 
 In the liquid form the molecules are not firmly held 
 together, but are capable of freer motion among them- 
 selves. 
 
 In the form of a gas, there is no attraction between 
 the molecules of the matter, but a law of repulsion _ 
 seems to exist which keeps the molecules apart. A gas 
 is called an elastic fluid. It is easily compressed, and its 
 density depends upon the amount of pressure to which 
 it is subjected. 
 
CHEMICAL ELEMENTS. 
 
 NAME. 
 
 
 it 
 
 2-1 
 
 J' 9 ! 
 
 if 
 
 
 H. 
 
 F. 
 CI. 
 
 B. 
 
 I. 
 
 Na. 
 K. 
 Li. 
 Ag. 
 Rb. 
 Cs. 
 Tl. 
 
 O. 
 
 s. 
 
 Ca. 
 Sr. 
 Ba. 
 Mg. 
 Zn. 
 
 Se- 
 Se. 
 Te. 
 Cd. 
 Gl. 
 Yt. 
 Ce. 
 La. 
 D. 
 E. 
 N. 
 P. 
 As. 
 Sb. 
 Au. 
 Bi. 
 B. 
 Ga. 
 C. 
 Sn. 
 Pb. 
 Pt. 
 Fe. 
 Si. 
 Al. 
 Ti. 
 Th. 
 In. 
 Pd. 
 Zr. 
 Cb. 
 Ta. 
 V. 
 Mn. 
 Cr. 
 Ni. 
 Co. 
 Ur. 
 Mo. 
 Wo. 
 Ru. 
 Ro. 
 Ir. 
 Os. 
 Ter. 
 Sc. 
 
 1 
 19 
 35 5 
 80 
 127 
 23 
 
 108 
 
 85.5 
 133 
 204 
 
 16 
 
 32 
 
 40 
 
 87.5 
 137 
 
 24 
 
 65 
 200 
 
 63.4 
 
 79 
 128 
 112 
 
 14 
 
 92.5 
 141 
 139 
 145 
 166.5 
 
 14 
 
 31 
 
 75 
 120 
 196 
 210 
 
 11 
 
 70 
 
 12 
 118 
 207 
 197 
 
 56 
 
 28 
 
 50 
 231 
 113 
 106 
 
 89.6 
 
 94 
 182 
 
 50 
 
 55 
 
 52.5 
 
 68 
 
 59 
 204 
 
 96 
 184 
 104 
 104 
 197 
 199 
 148.5 
 
 44 
 173 
 
 I. 
 
 I. 
 I. III. v. 
 I. III. v. 
 
 i. 
 i. in. 
 
 1. III. V. 
 
 I. 
 i. in. 
 
 i. 
 
 i. 
 i. in. 
 
 n. 
 
 II. IV. VI. 
 
 ii. 
 
 II. IV. 
 
 n. 
 ii. 
 ii. 
 
 Hg2. II. 
 
 II. 
 
 II. IV. VI. 
 
 II. IV. VI. 
 
 II. 
 
 n. 
 u. 
 
 II. IV. 
 
 II. 
 n. 
 n. 
 
 i. ni. v. 
 
 III. v. 
 III. v. 
 III. v. 
 
 ni. 
 
 III. v. 
 
 in. 
 in. 
 
 II. IV. 
 
 II. IV. 
 II. IV. 
 II. IV. 
 II. IV. 
 II. IV. 
 
 IV. VI. 
 II. IV. 
 II. IV. 
 
 II. 
 
 II. IV. 
 
 II. IV. 
 V. 
 V. 
 
 III. V. 
 II. IV. VI. 
 II. IV. VI. 
 II. TV. VI 
 II. IV. VI. 
 II. IV. VI. 
 II. IV. VI. 
 
 IV. VI. 
 
 ii. rv. vi. 
 
 II. IV. VI. 
 
 ii. rv. vi. 
 
 II. IV. VI. 
 
 + 
 
 
 Chlorine 
 
 - 
 
 
 
 Sodium {Natrium) 
 
 Potassium (Kalimn ) 
 
 
 
 
 
 Rubidium 
 
 
 Thallium 
 
 
 
 
 
 
 
 
 
 
 
 Barium 
 
 
 
 
 
 
 
 
 
 
 
 
 
 + 
 
 
 Yttrium 
 
 + 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 1 
 
 + 
 
 
 Boron 
 
 
 Tin (Stannum) 
 
 
 
 
 
 
 
 
 
 
 + 
 
 
 
 14- 
 
 
 
 
 
 
 1 
 
 
 
 
 
 
 
 
 + 
 
 Chromium 
 
 Cobalt 
 
 i 
 
 Tungsten ( Wolfram) 
 
 I 
 t 
 
 
 
 
 
 
 
 
 Ytterbium 
 
 
 
 
Very many substances can be made to assume all of 
 the states of matter, and to change backward and for- 
 ward from a solid to a liquid and to a gas ; or from a gas 
 to a liquid or solid. This is done by the application or 
 abstraction of pressure, or by the application or abstrac- 
 tion of heat. . 
 
 An Element, or a simple substance, is one which 
 cannot be subdivided into, or made to yield other sub- 
 
 A Compound, or a compound substance, is one com- 
 posed of the union of two or more elemental or simple 
 substances. A compound may be made to change its 
 character, and be resolved into two or more simple sub- 
 stances. 
 
 There are sixty-seven well-known elements. At our 
 usual temperature and atmospheric pressure, five of 
 these are gases (H. O. N. F. CI.); three are liquids 
 (B. Hg. Ga.), and the remainder are solids. 
 
 In the designation of the elements in chemical form- 
 ulas certain symbols are used. The symbol is either the 
 initial letter of the Latin name of the element, or the 
 initial letter followed by a suggestive letter from the 
 
 name. 
 
 A Symbol stands for the name of the element. It 
 also stands for one atom of the element ; for the weight 
 of one atom, the atomic weight of the element ; and for 
 one volume. ■ 
 
 An Atom is a most minute portion of a body ; an 
 indivisible particle of matter. 
 
 Atoms differ in weight, and in the quantity and qual- 
 ity of the power by which they unite with each other in 
 forming molecules,, m . 
 
 To all atoms are ascribed a definite relative weight. 
 
 The Atomic Weight of an element is the compar- 
 ative weight of a volume of the element, compared with 
 the same quantity of hydrogen, which, being the light- 
 est of all the elements, is taken as the standard of com- 
 parison, and this comparative weight of the element 
 given to an atom of the element is said to be the weight 
 of the atom. _ 
 
 When atoms unite to form molecules they obey the 
 inherent law of their natures— the law of chemism; and 
 
they unite in definite proportions which, in given com- 
 pounds, never vary. 
 
 Atoms are believed to be always united in the torm 
 of molecules. 
 
 A Simple Molecule is a molecule in which the 
 atoms are alike — an elemental molecule. 
 
 A Compound Molecule is one in which the atoms 
 are unlike. 
 
 We have said that atoms differ in the quantity of the 
 power with which they combine to form molecules. To 
 illustrate : One atom of chlorine will combine with one 
 atom of hydrogen, but one atom of oxygen will not 
 combine with less than two atoms of hydrogen, and one 
 atom of nitrogen demands three atoms of hydrogen, 
 and one atom of carbon demands four atoms of hydro- 
 gen. 
 
 The Equivalence or combining power of an atom 
 is the number of hydrogen atoms it would combine 
 with, or be equal to. 
 
 Atoms are called monads, or dyads, or triads, or tet- 
 rads, or pentads, or hexads, or heptads, as they demand 
 the equivalent of one, two, three, four, five, six or seven 
 atoms of hydrogen. 
 
 Some atoms vary in their combining powers, bul- 
 phur and oxygen may unite with one of sulphur and one 
 of oxygen, or one of sulphur and two of oxygen, 
 or one of sulphur and three of oxygen— never more 
 than three. Oxygen has two equivalences always. 
 If that is true, then the variation is in the sulphur. 
 When sulphur unites with one atom of oxygen, it has 
 two equivalences like the oxygen. When it unites with 
 two atoms of oxygen, it must have twice as many or four 
 equivalences, and when with three of oxygen it must 
 have six. 
 
 The variation in equivalences always increases or 
 diminishes by two. Thus an atom may combine with 
 one or three or five equivalences ; or two or four or six. 
 The equivalence of an atom is indicated by a Roman 
 numeral placed above and to the right of the symbol. 
 
 A Molecule is formed by the union of two or more 
 atoms. It is the smallest particle into which compound 
 matter can be divided and retain its identity. 
 
A Formula is the written representation of a mole- 
 cule, or of a reaction between molecules. 
 
 In Writing a Formula, the symbols of the constit- 
 uent elements are written side by side, and if more than 
 one atom is used, the number is placed a little below and 
 to the right of the symbol. 
 
 In multiplying molecules, the number of molecules to 
 be considered may be placed just before the formula, or 
 the formula may be enclosed in brackets and the number 
 placed just below and to the right. 
 
 A formula represents four things — the elements, the 
 number of atoms, the volumes of the substance and the 
 weight of the molecule — the molecular weight. 
 
 A Simple Molecule is one in which the atoms are 
 alike. It contains usually only two atoms, but there 
 may be as many as six. 
 
 A Compound Molecule is one in which the atoms 
 are unlike. It may contain any number of atoms. 
 
 There are two classes of compound molecules. 
 
 Those in which the unlike atoms unite directly are 
 called binary molecules, because, however many 
 atoms there may be, they are of only two hinds. 
 
 Those in which the unlike atoms are united by a 
 third atom. These are called ternary molecules, be- 
 cause there must be at least three kinds of atoms. 
 
 Electricity is the only force which seems to influence 
 the law of chemism. A current of electricity, passed 
 through a liquid compound, or a solution of a com- 
 pound, will cause the compound to decompose, and all 
 the atoms of one element will go to the positive pole of 
 the battery, and those of the other element will go to the 
 negative pole. Those which go to the positive pole are 
 called negative elements, and those that go to the 
 negative pole are called positive elements. 
 
 The elements of every compound molecule are united 
 with reference to their electro-chemical character. 
 
 An element, however, may be positive in one com- 
 pound and negative in another. Its electro-chemism is 
 not arbitrary. 
 
 In a binary molecule (a molecule with two kinds of 
 atoms) one of the elements will be positive to the other, 
 which is negative. 
 
In Naming the Compounds, the name of the pos- 
 itive element is written first, and the name of the nega- 
 tive element, with the ending ide, is written second ; 
 S"0" is the sulphur oxide. 
 
 The equivalence is also considered in the name. If 
 the elements combined are monads, then the name of 
 the positive does not change. If they are combined in 
 their highest equivalence, then the positive element ends 
 with ic ; S^ 0" 3 is the sulphur^ oxide. If they are 
 combined in their next to the highest equivalence, then 
 the positive element will take the ending ous; S lv O" 2 is 
 the sulphurous oxide. If there is a still lower combi- 
 nation, the positive element takes the prefix hypo, and 
 the suffix ous, also; S^O" is the hypo-sulphurous oxide. 
 If there is a higher combination than the ic compound, 
 the positive element takes the prefix per and the suffix ic. 
 There are numerical prefixes attached sometimes, 
 which also show the number of atoms. If one atom is 
 used, the prefix is mon; if two, di; if three, tri; if 
 four, tetr; if five, penta. 
 
 In the Ternary Molecules, one element which is 
 positive is united to another which is negative, by a 
 third element, which acts as the linking or uniting element. 
 The linking element will be found to exercise the 
 same function in very many ternary compounds, as 
 there are only a few which can exercise this function. 
 The commonest of these are oxygen, sulphur, and nitro- 
 gen, and the one which we will consider most is oxygen. 
 A molecule of water is written H 2 ; graphically 
 H-O-H. This type determines the structure of the ter- 
 nary molecules. It is called the water type. 
 
 The first class, called acids, are formed by the union 
 of a negative element by oxygen to hydrogen, which is 
 positive. 
 
 The second, called bases, are formed by the union of 
 an element which is positive by oxygen to hydrogen, 
 which is negative. 
 
 The third class, called salts, are formed by the union 
 of a negative element by oxygen to a positive element. 
 There is no hydrogen in a salt. 
 
 Acid. Base. Salt. 
 
 E-O-H E-O-H E-O-E 
 
An Acid is a sharp, sour substance which turns vege- 
 table blues red. 
 
 A Base — A basic substance, a hydrate, an alkali, is 
 the opposite of an acid. It has a peculiar taste, and 
 turns the red, produced by an acid, back to a blue. 
 
 A Salt occupies a neutral position ; is not chemically 
 active, and has no peculiar marked chemical properties. 
 The union of an acid and a base will form a salt and water. 
 
 All substances formed by the rule given for acids 
 are acids; but all the substances known in chemistry to 
 possess the properties of an acid, are not formed this 
 way. There are a few substances which have a binary 
 molecule, and yet have acid properties. 
 
 In the Naming of Ternary Compounds, instead 
 of the ide terminal of the binaries, the suffix ate or ite is 
 used to designate that oxygen unites two other elements. 
 
 If the elements are in their highest equivalence, the 
 ending of the negative element is ate; if in their next 
 lower equivalence, it is ite ; if lower yet, the prefix 
 hypo is subjoined to the negative. If higher than the 
 ate, it has the prefix per. 
 
 The commonest method of naming is to follow the 
 name of the characteristic element with the word acid 
 or base, and determine its equivalence by the same 
 suffixes as the binaries, ic or ous. 
 
 To illustrate : Hydrogen, which is positive, may be 
 united by oxygen to sulphur, which is negative. The 
 negative element sulphur, taking the ending ate, gives 
 the hydrogen sulphate, provided sulphur is in the equiva- 
 lence of a hexad ; if it is next lower — a tetrad — the 
 the compound would be hydrogen sulphite', if still lower, 
 it would be the hydrogen hyposulphite. 
 
 This compound is an acid. Considering sulphur as 
 the characteristic element, the compound is a sulphur 
 acid. In the highest equivalence of the sulphur, it is 
 sulphuric acid ; in the next lower it is the sulphuiYWs 
 acid ; and still lower the /lyposulphurous acid. 
 
 In a careful study of all the ternary compounds, we 
 find that all of them may be placed in a few classes, and 
 that in each class there is a group of atoms which is 
 present in every compound of that class. The groups 
 of atoms are called radicals. 
 
A Radical is an atom or an unsaturated group of 
 atoms, which is found present as characteristic of dis- 
 tinct classes of compound molecules. 
 
 A radical has one, two, three, or more unsatisfied 
 bonds or equivalences like atoms, and is thus known as 
 a monad, dyad or triad radical. 
 
 The hydroxyl radical (HO)' forms the hydrates. The 
 nitrosyl radical (N0 3 )' forms the nitrates. The am- 
 monium radical (NH 4 )' forms the ammonium com- 
 pounds. The chloryl radical (C10 3 )' forms the chlorates. 
 The sulphuryl radical (S0 4 )" forms the sulphates. The 
 carbonyl radical (CO s )" forms the carbonates. The chro- 
 myl radical (Cr0 4 )" forms the chromates. The phos- 
 phoryl radical (P0 4 )'" forms the phosphates. The 
 cyanogen radical (CN)' forms the cyanides. 
 
 If we closely observe the structure of bases, we ob- 
 serve that they are compounds of the hydroxyl radical, 
 and are thus called hydrates. 
 
 There are a class of compounds which are the ano- 
 logues of the acids, bases and salts, formed from the 
 ammonium radical. These are called amides, amines 
 and alkalamid.es, or ternary compounds, in which nitro- 
 gen instead of oxygen is the linking element. 
 
 An Amide is a compound in which a negative ele- 
 ment is united by nitrogen to hydrogen, which is posi- 
 tive. 
 
 An Amine is a compound in which a positive ele- 
 ment is united by nitrogen to hydrogen which is nega- 
 tive. 
 
 An Alkalamide is a compound in which a negative 
 element is united by nitrogen to a positive element. 
 
 I have said that each atom represents one volume, 
 and each molecule represents two volumes. 
 
 Ampere's Law. Ampere asserted that equal vol- 
 umes of all substances in a state of gas must contain 
 the same number of molecules. 
 
 If this is true, all molecules must be of the same size ; 
 and if all molecules are the same size, a molecule contain- 
 ing one hundred atoms must have those atoms crowded 
 into the same space as two atoms would fill, in a molecule 
 containing only two. 
 
 This fact accounts for the change of size or volume 
 
when certain substances change their chemical charac- 
 ters ; and it also accounts for the change in the density 
 or weight of the substances. 
 
 If equal volumes of different substances contain the 
 same number of molecules, and there is a difference in 
 the weight of the separate molecules, there would be 
 the same difference in the weight of the volumes. 
 
 A molecule of hydrogen weighs one ; a molecule of 
 nitrogen weighs 14 times as much ; one of oxygen 
 weighs 16 times as much, and one of chlorine weights 
 35.5 times as much. These facts being true, equal vol- 
 umes of these substances must weigh in exactly the 
 same proportions. 
 
 It will be observed that the weight of these molecules 
 and volumes correspond exactly with the atomic weights 
 of the elements represented. 
 
 The atomic weights of the separate elements in a 
 compound represents the exact comparative weights of 
 the substances in any quantity of the compound. 
 
 The carbonate of calcium has this formula, CaC0 3 , 
 that is, one atom of calcium, atomic weight, 40 ; one 
 atom of carbon, atomic weight, 12, and three atoms of 
 oxygen, each weighing 16, the three weighing 48. The 
 molecule, then, weighs 404-124-48, or 100. That is 
 one hundred times as much as one hydrogen atom. 
 
 If we had 100 pounds of the carbonate of calcium 
 the proportions would be exactly the same, i.e.: 40 lbs. 
 of carbon, 12 lbs. of calcium, and 48 lbs. of oxygen. 
 
 Changes taking place between chemical substances 
 can be estimated exactly on the basis of their atomic 
 weights. 
 
 The following rules will determine the amount of any 
 constituent of a compound in a given quantity of the 
 compound : 
 
 Rule. — Multiply the atomic weight of the unknown 
 substance by the weight of the quantity, and divide 
 that product by the molecular weight of the compound. 
 
 By applying the above rule to each one of the con- 
 stituents of a compound, the sum of the results should 
 equal the total quantity. 
 
 To determine the per cent, of any one constituent 
 in the compound : Multiply the atomic weight of that 
 n 
 
constituent by 100, and divide that product by the 
 molecular weight of the compound. 
 
 Knowing the percentage amounts of the constituents, 
 to determine the amount of any constituent in a given 
 quantity of the compound: Multiply the quantity by 
 the percentage amount of the unknown constituent, and 
 the product will be the amount of that constituent in 
 the given quantity. 
 
 INORGANIC CHEMISTRY. 
 
 Chapter II. 
 
 HYDROGEN. 
 
 Symbol H', Atomic weight, 1. 
 Hydrogen is an invisible, colorless, odorless, tasteless 
 gas. It is the lightest substance known. It is 14.45 
 times lighter than air, and 11,000 times lighter than 
 water, 100 cubic inches weighs 2.15 grains. One grain 
 measures 43.75 cubic inches. It is slightly soluble in 
 water ; one and one-half volumes of the gas will dissolve 
 in 100 volumes of water. Because of its lightness it is 
 taken as the standard of density, atomic and molecular 
 weight and volume. It is combustible and respirable, but 
 will not support combustion or respiration. Heated 
 with oxygen, they will unite with an explosion ; mixed 
 with chlorine and exposed to strong sunlight, they will 
 unite, otherwise it is not chemically active. A pressure 
 of 650 atmospheres will reduce hydrogen to a liquid. 
 Many metals will absorb hydrogen, notably palladium, 
 one volume of which will take up 900 volumes of the 
 gas. Graham maintained that under these circumstances, 
 hydrogen is a metal, with a density of 2., and he called 
 it hydrogenium. Hydrogen was known 300 years ago. 
 It occurs in the exhalations of volcanoes, and composes 
 the larger portion of the atmosphere of some of the 
 fixed stars. The iron of Leonarto contains a large 
 quantity of hydrogen gas. It exists in water, and in 
 most organic substances, and in acid and basic substances. 
 It can be obtained from water, by decomposing the 
 
 12 
 
water with potassium, sodium or electricity, or with iron 
 at a red heat, the oxygen of the water uniting with the 
 elements used, form an oxide, and the hydrogen is set free. 
 By acting on an acid with a metallic substance, hydrogen 
 is set free, as: H 2 S0 4 +Zn=ZuS0. 1 +H 2 . Hydrogen, 
 because of its lightness, was originally used to inflate 
 balloons. In later years less expensive compound gases 
 serve the purpose equally well. It is used in combus- 
 tion to produce great heat. Hydrogen enters into very 
 many compounds, which will be considered in their 
 proper order. 
 
 The Nascent State of an element named (from 
 nascere, being born) is the condition of the atoms of the 
 element at the inappreciable moment when they are 
 neither united with atoms of their own or other kinds ; 
 or the time between the moment of the liberation of the 
 atoms from one compound, and their union to form any 
 other compound. It is reasonable to suppose that their 
 chemical energy, unsatisfied at just this brief moment, is 
 in its full exercise, or that the energy is just the amount 
 greater that would be necessary to decompose a satisfied 
 molecule, once formed ; whether that be a simple mole- 
 cule, or a compound molecule. 
 
 OXYGEN. 
 
 Symbol O". Atomic weight, 16. 
 
 Oxygen is probably the most important of all 
 chemical elements. It is a colorless, odorless, tasteless 
 gas, 16 times heavier than hydrogen, 100 cubic inches 
 weighs 34.25 grains. It is slightly soluble in water, 3 
 volumes of oxygen in 100 volumes of water. Chemi- 
 cally, it is very active. It is not combustible, but is 
 the typical supporter of combustion. It unites directly 
 with all elements, except fluorine, to form oxides. The 
 union of oxygen with other substances, notably with 
 carbon, accompanied with light and heat, is called 
 combustion. It is the element which supports respira- 
 tion. At a pressure of 300 atmospheres, and a temper- 
 ature of — 220° Fah., it becomes a liquid. 
 
 Oxygen was discovered in 1774 by Priestly; he called 
 it dephlogisticated air. The following year Scheele dis- 
 covered it and called it empyreal air. Lavosier gave it 
 
the name of oxygen, from two Greek words, signifying 
 an ' ' acid former. " 
 
 It is the most abundant element in nature. It com- 
 poses eight-ninths of the weight of water, one-fifth of 
 the air, three-fourths of the weight of animals, four- 
 fifths of the weight of vegetables and one-half of the weight 
 of minerals. In fact, it constitutes more than 65 per 
 cent, of the globe. It unites to form compounds with 
 every element except fluorine. 
 
 Although so common in its occurrence, it is difficult 
 to obtain free in large quantities. It may be obtained 
 from the decomposition of water by electricity, and 
 from the mercuric oxide by heat, or by heating the 
 chlorate of potassium, facilitated by the presence of the 
 black oxide of manganese. The reaction which takes 
 place in the latter case is the following : (KC10 3 ) 2 + 
 Heat, = (KC1) 3 + (0 2 ) 3 . One ounce of the chlorate 
 will yield more than one gallon of oxygen gas. 
 
 Oxygen is essential to animal life. It is inhaled into 
 the lungs and, passing through the thin walls of the air 
 vesicles by diffusion, enters directly into the blood, com- 
 bines directly with the hsenioglobin, and oxidizes the 
 waste products of the system within the circulation. 
 One hundred volumes of the arterial blood in a dog con- 
 tained twenty-two volumes of oxygen. It becomes a 
 part of the tissues, and assists in the production of body 
 heat. It stores up also the vital force in the food and 
 imparts it to the animal. 
 
 It is used in the arts to increase the intensity of com- 
 bustion, in the production of great heat. 
 
 OZONE AND ANTOZONE. 
 
 Symbols (<9 3 ) and (O). 
 Oxygen is a dyad under ordinary circumstances, and 
 the molecule is composed of two atoms. It may exist 
 under forced circumstances with three atoms in the 
 molecule, or with only one atom in the molecule. In the 
 former case it is called ozone, and in the latter, anto- 
 zone ; or, active oxygen. The molecule of oxygen is be- 
 lieved to be formed like this : 0~0. The molecule of 
 ozone is formed like this: o<§, and that of antozone 
 like this : 0> , (0 2 ) (0 3 ) and (O). If the density of a 
 
substance is equal to one-half of its molecular weight, 
 then the density of oxygen is 16, the density of ozone is 
 24 and that of antozone is 8. These substances exist in 
 the air after a violent thunderstorm from the decompo- 
 sition or rearrangement of the oxygen molecule by elec- 
 tricity. Ozone is best known; it has a peculiar sul- 
 phurous odor, and has a powerful purifying influence. 
 It is an active disinfectant. It is concentrated oxygen. 
 
 WATER. 
 
 H 2 0. Di Hydrogen Oxide. 
 
 Water is a stable liquid — limpid, mobile, odorless, 
 colorless, tasteless, neutral — a poor conductor of heat, a 
 better conductor of electricity. It is 773 times heavier 
 than air, 11,143 times heavier than hydrogen. Within 
 range of 180° Fah., it will exist in the three states of 
 matter — a solid at and below 32°, a liquid between 32° 
 and 212° and a vapor above 212°. 
 
 There is a great change in volume between the liquid 
 and gaseous forms, one volume of the former producing 
 1,700 volumes of the latter. By the action of cold, 
 water contracts to a point equal to 39 1-9° Fah.; below 
 that it slowly expands. This is the point of maximum 
 density of water. 
 
 In 1781 Cavendish proved the composition of water, 
 and in 1805 it was proved that one ounce of water was 
 produced from 2,500 cubic inches of the mixed gases, 
 hydrogen and oxygen, in the proportion of two volumes 
 of the former to one of the latter. 
 
 Water occurs abundantly in nature, free, and in com- 
 bination. It may be formed synthetically, by burning 
 together hydrogen and oxygen gases. 
 
 In the economy of nature, water is most important. 
 It is an almost universal solvent, and by this property it 
 supplies nutrition to all life. Seven-eighths of the hu- 
 man body is water. It is taken in by food, drink and 
 respiration. It enters into the composition of rocks, 
 and determines the crystallization of all crystalline bodies. 
 HYDROGEN DI-OXIDE. • 
 
 H % 2 . Free Hydroxyl. 
 Hydrogen di-oxide; peroxide of hydrogen, or 
 oxygenated water, is a colorless, syrupy liquid. It 
 
contains an excess of oxygen, and is thus a powerful 
 oxidizer. It will not freeze at — 30° Fahrenheit, and in a 
 vacuum it may be evaporated unchanged. It is very 
 unstable, readily giving up an atom of oxygen from 
 every molecule. Diluted with water, it is more per- 
 manent. It bleaches all vegetable colors. 
 
 It was discovered in 1818 by Thenard. It may be 
 prepared by the action of hydro carbonic acid and the 
 barium di-oxide with the reaction — Ba0 2 +H 2 (C0 3 )= 
 Ba(C0 3 )+H 2 2 . 
 
 This agent is a valuable therapeutic agent. In sur- 
 gery it is an active disinfectant, prevents the formation 
 of pus, and stimulates to healthy granulation. It is 
 also used in the manufacture of oxygen gas in small 
 quantities. 
 
 NITROGEN. 
 
 Symbol, iV x ~ III_v - Atomic weight, 11^. 
 
 Nitrogen is a colorless, odorless, tasteless gas; 100 
 cubic inches weighs 30.14 grains. It will not burn nor 
 support combustion. It is respirable, but will not sup- 
 port respiration. It is not poisonous. It is soluble 
 in water, one volume of the gas to fifty volumes of 
 water. In its elemental form it is chemically inactive, 
 but its compounds are all violently active. 
 
 It was discovered by Rutherford in 1774, and because 
 it would not support life, he called it Azote. Afterward 
 it was called Nitrogen, — the "nitre former." 
 
 It composes four-fifths of the atmosphere, and is 
 found free in the gases of the stomach and intestines. 
 It is found in combination in vegetable and animal 
 bodies, in ammonia, and in combination with alkalies 
 in the earth. It may be freed from admixture with 
 oxygen in the air by removing the oxygen by the oxida- 
 tion of some metals and phosphorus. 
 
 Nitrogen dilutes the oxygen in respiration, and facili- 
 tates the functions of that important clement. It is an 
 essential constituent of the animal economy, but is sup- 
 plied principally through the food. It is not used in 
 the arts. 
 
 Its commonest compounds are ammonia and the am- 
 monium compounds, NH 3 and (NH 4 )' and the oxides 
 and acids of nitrogen, and it enters into all the nitrates. 
 
THE ATMOSPHERE. 
 
 Air is the gaseous envelope which encircles the earth. 
 It is a mixture of gases, and not a chemical combina- 
 tion; yet it is very constant in its composition. 
 
 The complex character of the air was discovered in 
 1669 by Mayow. The quantity, or proportion of its 
 constituents, was discovered in 1771 by Priestly. 
 
 The air is composed of two free gases, oxygen and 
 nitrogen, mixed with unvarying uniformity by the law 
 of diffusion in the proportions of 20.93 parts of 
 oxygen by volume or 23 parts by weight, and 79.07 
 parts of nitrogen by volume or 77 parts by weight. 
 In addition to these there is water vapor, and the 
 nitrogen oxides, and carbonic acid gas, and ammonia, 
 and ozone. And there is. also dust, sodium chloride,- 
 spores, germs, animalcules, insects and eggs. 
 
 The composition of the air is proved in three ways :_ 
 
 1st. The gases are not present in proportion of their 
 atomic weight. . 
 
 2d. The gases can be mixed mechanically, and a 
 perfect atmosphere produced. 
 
 3d. Each of the gases dissolves in water according 
 to its individual solubility, perfectly independent of the 
 other. . 
 
 The height of the air is not known, but is believed to 
 be no less than 200 miles, with the greatest density 
 nearest the earth, one half of the entire quantity being 
 within 2i miles of the earth. Yet, notwithstanding the 
 difference in density, there is no difference in the pro- 
 portions of the ingredients. < ; 
 
 It is impossible to name all the uses of the air. It is 
 essential to respiration, and the support of all life, and 
 is also essential to the laws which control the earth in 
 itself. 
 
 DIFFUSION. 
 
 If the mouths of two jars containing different gases 
 be brought together so that the gases are in contact, and 
 allowed to remain at rest a given time, it will be found 
 that there is a uniform mechanical admixture of the 
 gases in each of the j ars. If a porous partition be placed 
 between the two jars the result will be the same. This 
 is called diffusion. 
 
Physics asserts that the molecules of all gases are 
 ever in motion in straight lines, and as molecules differ 
 in weight, the lighter ones must move correspondingly 
 faster than the smaller ones to offer the same resistance 
 to the outward medium of pressure. If this is true a 
 lighter gas will diffuse itself more quickly than a heavier 
 
 Graham's Law is that the velocity of diffusion of 
 two gases is inversely proportional to the square roots 
 of their densities. 
 
 AMMONIA. 
 
 N'"II\. 
 
 Ammonia is an intensely pungent, irrespirable gas, 
 colorless and transparent, does not burn or support com- 
 bustion. It is alkline in its taste and in its reaction, and 
 is called volatile alkali. It is about half as heavy as the 
 air, and is very soluble in water. At the freezing point 
 one volume of water will dissolve 1,150 volumes of 
 ammonia, forming the well known aqua ammonia, or 
 the ammonium hydrate. At a temperature of 40°, or 
 under pressure of only 6.5 atmospheres, it is reduced to 
 a colorless, mobile, unstable liquid. This liquid will 
 solidify at —103° Fan., it volatilizes rapidly with the 
 abstraction of heat. 
 
 Ammonia was known to the old alchemists 600 years 
 ao-o In 1TY4 Priestly separated it as a gas, and called 
 if alkaline air, although Black had obtained it free in 
 
 It is produced by the decomposition of organic matter 
 containing nitrogen. It is given off in the decomposi- 
 tion of animal urine, and in the burning of horn, hair 
 or hides. It was first obtained from the distillation of 
 camel's dung, near the temple of Jupiter Ammon in the 
 Libyan desert. It is an important constituent of guano. 
 Coal contains two per cent, of nitrogen, and when the 
 coal is distilled in the production of illuminating gas, a 
 strong ammoniacal liquor remains as a by-product, from 
 which ammonia gas is now manufactured. 
 
 Ammonia may be produced by acting upon nitric acid 
 with zinc, with the following reaction (HN0 3 ) 9 +ZnV- 
 (Zn"(N0 3 ).)4+(H,0) 3 +NH 3 . It may also be prepared by 
 actin^ on muriate of ammonium— ammonium chloride, 
 
with quick lime (NH 4 )Cl) 2 +CaO=CaCl 2 +H 2 0+(NH 3 ) 2 . 
 Ammonia is a powerful stimulant, and is a valuable 
 therapeutic agent. The salts are used internally very 
 freely. It is a powerful escharotic. In sufficient quan- 
 tities it is violently poisonous. It is used in the arts for 
 many important purposes. 
 
 AMMONIUM COMPOUNDS. 
 
 There is a large number of compounds which belong 
 to the same family, and are found to contain in their 
 chemical structure the group of atoms, or the radical 
 
 (NH 4 y. 
 
 These are called the ammonium compounds from the 
 radical which is called the ammonium radical. No sub- 
 stance has ever been isolated which was known to be 
 free ammonium. Weyl claimed that he had obtained a 
 substance with the formula (NH 4 ) 2 . Although never 
 free it acts similar in all its compounds to the metals 
 sodium and potassium. And its compounds are the 
 analogues of the compounds of these metals. 
 
 Ammonium Hydrate (NH 4 )HO, is the result of 
 the action of water upon ammonia gas, NH 3 +H 2 0= 
 (NH 4 )HO. It is an unstable, pungent, mobile liquid, 
 giving off the vapor of ammonia. 
 
 Ammonium Sulphate (NH 4 ) 2 (S0 4 ) is obtained by 
 acting upon the ammoniacal liquor from gas works 
 with sulphuric acid. It is a crystalline body, easily 
 soluble in water. 
 
 Ammonium Carbonate (NH 4 ) 2 C0 3 or sesqui-car- 
 bonate is prepared by heating the carbonate of calcium 
 and the chloride of ammonium together and condensing 
 the volatilized product. It is a hard mass; translucent; 
 and it gives off the characteristic odor of ammonia. It 
 is unstable. 
 
 Ammonium Nitrate (NH 4 )N0 3 is a crystalline 
 body formed by the action of the ammonium hydrate 
 upon nitric acid. It is readily soluble in water and 
 melts at 300° Fah. 
 
 Ammonium Chloride (NH 4 C1) — Muriate of am- 
 monium or sal-ammoniac is a common ammonium salt. 
 It is prepared by acting upon the ammoniacal liquor of 
 gas works with hydrochloric acid and subliming the 
 
 19 
 
evaporated product. Its crystallization is peculiar. It 
 forms a fibrous tough mass with a pungent salty taste. 
 
 Ammonium Bromide (NH 4 )Br. may be formed 
 by the direct union of ammonia and hydrobromic acid. 
 It is a granular powder, which alters its color on expos- 
 ure to light. 
 
 Ammonium Iodide (NH 4 )I, is a crystalline body, 
 very deliquescent. It decomposes in the air giving out 
 the odor of iodine. It is formed by the action of 
 hydriodic acid and ammonia. 
 
 HYPO NITROUS OXIDE. 
 
 N % 0. Laughing Gas. 
 
 Hypo Nitrous Oxide is the gas which was first 
 used as an anaesthetic. It is a rather heavy gas, color- 
 less and odorless, but with a sweetish taste. It is one 
 and one-half times heavier than air. It is soluble in 
 water — 100 volumes of water will dissolve 78 volumes 
 of the gas. At a pressure of 30 atmospheres, and at 
 zero of the thermometer, it becomes a colorless, mobile 
 liquid, which, if dissolved in the bi-sulphide of carbon 
 and evaporated in a vacuum, will produce the lowest 
 known temperature — 220° Fahrenheit. It is a very 
 unstable liquid, and explodes readily. This gas will 
 sustain respiration and support combustion. 
 
 Laughing gas was discovered by Priestly in 1776, 
 and was used as an anaesthetic by Wells in 1846. 
 
 It may be obtained by the distillation of the ammon- 
 ium nitrate, with this reaction — (N0 3 XNH 4 ) 2 +Heat= 
 (H 2 0) 4 +(N 2 0) 2 . 
 
 Hypo nitrous oxide is used largely as an anaesthetic 
 at the present time, in minor surgery, and in dentistry, 
 when a transient effect is desired. It is used as an in- 
 halant in pulmonary troubles, and in those cases de- 
 manding more perfect aeration of the blood. 
 
 NITRIC ACID. 
 
 H(NO s ). Hydrogen Nitrate. 
 
 Nitric acid, or aqua fortis, is one of the commonest 
 
 and most useful of the acids. In its pure state it is a 
 
 heavy, colorless, fuming liquid, with a specific gravity 
 
 of 1.52. It boils at 187° Fah. and freezes at —40°. It 
 
is not a stable acid, but changes its character by beat or 
 when exposed to the air. Jt acts violently upon all or- 
 ganic substances, and upon metals, either alone or in 
 their compounds. Its union with non-nitrogenous or- 
 ganic substances, such as sugar, glycerine, and cotton 
 forms explosive compounds. 
 
 There are at least five varieties of nitric acid in com- 
 merce and pharmacy : First — The pure acid, just de- 
 scribed, marked C. P. (chemically pure). It must be 
 kept in strong smoked glass bottles in the dark, the 
 bottles always full, and stopped with glass stoppers, 
 sealed with paraffine. Second — The Commercial Aqua 
 Fortis, a yellowish, very impure liquid, too impure for 
 chemistry or pharmacy. It may contain arsenic, iron, 
 sulphuric, or hydrochloric acid, and the nitrogen oxides 
 as impurities. It is also in two strengths: the single 
 acid contains 39 per cent, of the strong acid, and the 
 double acid contains 64 per cent. Third — The Fuming 
 Nitric Acid, highly concentrated; more or less free from 
 impurities. It is of a reddish yellow color, and is a 
 powerful oxidant. Fourth — The U.S. P. Acid. It 
 contains TO per cent, of the C. P. concentrated acid; is 
 a valuable caustic and escharotic. Fifth — The Dilute 
 U.S. P. Acid. It contains only 10 per cent, of the C. 
 P. acid. The B. P. acid contains 17.44 per cent. 
 
 Nitric acid may be prepared by the action of sul- 
 phuric acid upon the nitrate of sodium, or potassium, in 
 a glass retort. Na(N0 3 )+H 2 (S0 4 )=HNa(S0 4 )-f H(N0 3 ). 
 The nitric acid is driven off by distillation. 
 
 Nitric acid was known in the eighth century. Ray- 
 mond Lully, in the eleventh century, described its com- 
 position fully. 
 
 It has many uses in the arts and manufactures, in 
 medicine and chemistry. 
 
 Nitric acid produces on animal tissues a characteristic 
 yellowish discoloration, by which its action may be 
 known. 
 
 When a poisonous dose of any corrosive acid has been 
 taken, neutralize at once by soap and water, or carbon- 
 ate of magnesia in water, or lime water. Don't waste 
 time with oils, and do not use the stomach pump, as 
 perforation may occur. 
 
 21 
 
THE HALOGENS. 
 
 The four elements— fluorine, chlorine, bromine and 
 iodine — when studied together, seem to exhibit a re- 
 markable relationship. If anything positive is known 
 of fluorine, it is a light gas ; chlorine is a heavy gas ; 
 bromine a liquid, and iodine a solid. As there is an in- 
 crease in their atomic weights, there is a decrease in 
 their comparative chemical activity. Their specific grav- 
 ity, freezing point and boiling point, rises as their 
 atomic weights increase. They are electro-chemically neg- 
 ative ; all have a characteristic odor, and are excellent 
 disinfectants and bleaching agents. They all combine 
 energetically with metals forming similarly constructed 
 compounds, or isomorphous compounds, with the same 
 element ; that is, crystallizing with the same peculiari- 
 ties. Because of the resemblance in their sodium, potas- 
 sium and other salts, they are called the halogens, or ' 'salt 
 formers," and their salts are called the haloid salts. 
 
 FLUORINE AND HYDROFLUORIC ACID. 
 
 Symbol F. Atomic weight, 19. HF. 
 
 Fluorine has not yet been isolated. It is always found 
 in combination with calcium, silicon, aluminum or 
 sodium. Its chemical activity is so great that it enters 
 into direct union with the substance of the vessel in 
 which it is received when liberated. The fluorides of 
 calcium {fluor spar), sodium and aluminum (cryolite), 
 and hydrofluoric acid, are well known. 
 
 Hydrofluoric Acid is the congener of hydrobromic, 
 hydrochloric and hydriodic acids. It is an intensely 
 corrosive acid, attacking glass and all vessels containing 
 silicon. Its fumes are dangerously irritating, and must 
 not be inhaled. 
 
 CHLORINE. 
 
 Symbol CI. Atomic weight, 35.5. 
 Chlorine is one of the heaviest of the gases. It is a 
 greenish yellow, pungent, irritating, suffocating gas. It 
 is irrespirable, and will neither burn nor support com- 
 bustion under ordinary circumstances. It is soluble in 
 water, one volume of which will dissolve three volumes 
 of the gas, producing a quite stable liquid, chlorine 
 
water. It is 2.5 times heavier than air, and may be 
 easily reduced to a liquid at a pressure of four atmos- 
 pheres, producing a dark yellow unstable liquid. It is 
 an active substance chemically, in its usual form, but if 
 prepared in the dark, it is inactive or passive. It unites 
 most readily with hydrogen, and to this is due the fact 
 that it possesses powerful bleaching and disinfectant 
 properties. It abstracts the hydrogen from the water 
 present and sets the oxygen free, which is really the 
 active agent. 
 
 Chlorine was discovered by Scheele in 1774. He 
 called it " dephlogisticated muriatic acid." In 1810, 
 Sir Humphrey Davy established its elemental character, 
 and named it chlorine, from the Greek word Chloros, 
 green, because of its green color. It is never found free, 
 but is very common in combination with sodium, potas- 
 sium, magnesium and calcium. Every quart of sea 
 water, because of the presence of these compounds, 
 contains nearly five quarts of chlorine gas. 
 
 Chlorine may be obtained by acting upon common 
 salt, NaCl, and black oxide of manganese with sulphuric 
 acid. This is the reaction : (NaCl) 2 +(H 2 (S0 4 )) 2 +Mn0 2 
 =Mn(S0 4 )+Na 2 (S0 4 )+(H 2 0),+Cl 2 . It is collected in 
 the bottom of an upright jar, by the upward displace- 
 ment of air. It may also be obtained by the action of 
 hydrochloric acid on the black oxide of manganese with 
 this reaction : Mn0 2 +(HCl) 4 =MnCl 2 +(H 2 0) 2 +Cl 2 . 
 
 . Chlorine is a powerful disinfectant, and many of its 
 compounds are useful for that purpose. It destroys 
 many organic coloring substances, thus acting as a pow- 
 erful bleaching agent. 
 
 HYDROCHLORIC ACID. 
 HCl. 
 
 Chlorine unites directly with hydrogen, forming a gas 
 called hydrochloric acid gas. The old alchemists 
 called this the spirit of sea salt. It is a colorless gas, 
 with a pungent odor and a shaip acid taste. It fumes 
 strongly in the air, is irrespirable, and injurious to veg- 
 etation. It will neither burn, nor support combustion. 
 It may be reduced to a liquid by a pressure of 40 atmos- 
 pheres, at a temperature of — 50° Fan., which is the pure 
 
 33 
 
acid, and is intensely corrosive. Glauber, in the 17th 
 century, called this gas muriatic acid, from the Latin 
 muria, or brine. Sir Humphrey Davy discovered its 
 true composition in 1810. 
 
 It is obtained by the action of sulphuric acid on com- 
 mon salt, with this reaction : H 2 S04+(NaCl) 2 =Na^S0 4 
 
 +(HCi) 2 . , ; t. 
 
 The liquid hydrochloric acid of commerce and phar- 
 macy is a solution of the gas in water. It is a colorless 
 liquid when pure, with all the characteristic acid prop- 
 erties of a strong mineral acid. The officinal hydro- 
 chloric acid contains 31.9 per cent, of the gaseous acid, 
 and has a specific gravity of 1.16. The dilute acid of 
 the pharmacopcea contains only 10 per cent, of the gas. 
 
 Hydrochloric acid is a valuable therapeutic agent, it 
 is the free acid of the gastric juice, and is important in 
 assisting digestion. It also has abundant uses in the 
 arts. 
 
 SODIUM CHLORIDE, 
 
 NaCl. 
 
 Common Salt is obtained from sea water, by allow- 
 ing the water to evaporate in shallow vats or pans. The 
 salt being easily crystallizable, crystallizes out of the 
 concentrated liquid, and the mother liquor is poured off 
 and the salt collected. Vast beds of rock salt, and 
 mines of salt are found in various parts of the world. 
 
 This substance has been long known. It is very sol- 
 uble in water, and is used as a preservative of various 
 substances. It is used in the arts and in manufactures. 
 It is found in all plant life, and is present in every tissue 
 and fluid of the animal body. 
 
 BROMINE. 
 
 Symbol Br. Atomic weight, 80. 
 Bromine is a heavy, blood-red, fuming liquid. It 
 has a strong, irritating, offensive, pungent odor, and is 
 corrosive to animal tissues. It fames at all tempera- 
 tures above its freezing point. It boils at 145.4° Fan., 
 and freezes at —12°. It is slightly soluble in water, one 
 part of bromine in 33 parts of water, at 60° Fah., is 
 freely soluble in alcohol, chloroform, ether and the car- 
 bon di-sulphide. It is similar to chlorine in its action, 
 
but is less active. It colors starch yellow, and precipi- 
 tates silver from its solutions. 
 
 It was discovered by Balard, in 1824, in sea water. 
 
 It is not found free, but always in combination with 
 the alkalies and magnesium in sea water and mineral 
 springs. 
 
 It is obtained from sea water. The water is evapor- 
 ated until the more easily crystallizable salts are precip- 
 itated. The mother liquor (Bittern) is then treated with 
 sulphuric acid, and the black oxide of manganese, which 
 sets chlorine free in the mixture, which, from its su- 
 perior chemical activity, replaces the bromine, setting 
 it free in the form of a vapor, which is conducted into 
 a cooled receiver and condensed. 
 
 Bromine is used quite freely in therapeutics, in its 
 compounds, and as a disinfecting and decolorizing agent. 
 It is used in photography. 
 
 The common compounds of bromine are the hydro- 
 bromic acid, HBr, and the bromides of sodium, 
 potassium, and magnesium. 
 
 HYDROGEN BROMIDE. 
 
 HBr. Hydrobromic Acid. 
 Hydrobromic Acid gas is colorless, fumes strongly 
 in the air, is readily soluble in water, forming a solu- 
 tion of the acid with properties similar to hydrochloric 
 
 It is prepared by treating phosphorus under cold 
 water with bromine, and distilling the liquid. Squibb 
 prepares it by acting on a hot solution of bromide ot 
 potassium with sulphuric acid. The reaction with the 
 phosphorus in water is this: P4+(Br 2 )io==(-^^r 5 ) 4 i- 
 (H 2 O) 18 =(H 3 PO 4 ) 4 +(HBr) 20 . 
 
 The solution of hydrobromic acid gas in water pro- 
 duces the liquid acid of pharmacy. It is a colorless 
 liquid with the characteristic properties ot a mineral 
 acid. The official acid contains about 10 per cent, ot 
 the gas. . 
 
 It is a useful medicine, acting more efficiently than 
 any other of the bromides. It is a sedative and nerve 
 tonic. 
 
IODINE. 
 
 Symbol I. Atomic weight, 127. 
 
 Iodine is a purplish black crystalline solid, very 
 slightly soluble in water, one part dissolving in 7,000 
 parts of the water. It is readily soluble in alcohol, 
 ether, carbon disulphide and chloroform. It is the 
 least active of the halogens. It is not an active poison, 
 but destroys tissue and turns the skin yellow. It reacts 
 readily with starch, forming the deep blue starch iodide. 
 This reaction will detect the presence of iodine in 
 300,000 parts of water. The di-sulphide of carbon 
 will react upon iodine in a million parts of water, pro- 
 ducing a peculiar purplish color. Iodine melts at 225° 
 Fahrenheit and boils at 347°, gives off a purplish vapor 
 and sublimes at all ordinary temperatures. 
 
 It was discovered by Courtois in 1811 in the mother 
 liquor of a solution of the ashes of seaweed, from 
 which the soda salts had been precipitated by crystalli- 
 zation. It received its name from its violet colored 
 vapor. It is never found free, but always in combina- 
 tion with an alkali or magnesium, in the ashes of sea 
 weeds and in sea water. 
 
 It is a valuable medicine, free and combined with 
 metals and alkalies. It is used also in photography. 
 
 The common compounds of iodine are the hydriodic 
 acid, HI, the oxides and the iodides of potassium, 
 sodium, magnesium, calcium and iron. 
 
 HYDROGEN IODIDE. 
 
 HI. Hydriodic Acid. 
 
 Hydriodic Acid is a colorless gas with a strong 
 acid reaction, and fumes in the air. It is easily con- 
 densed into a liquid at a pressure of four atmospheres. 
 It is as soluble as the hydrochloric acid gas in water, 
 and its saturated solution gives the liquid (hydriodic) 
 acid, which has a specific gravity of 1.7, boils at 2.60° 
 Fahrenheit and contains 57 per cent, of the gaseous 
 acid. 
 
 The solution of the hydriodic acid gas in water yields 
 a colorless liquid, with the characteristic properties of a 
 mineral acid. It has a specific gravity of 1.7, and con- 
 tains 57 per cent, of the gaseous acid. 
 
Hyclriodic acid is assuming an important place in 
 medicine. It is used in the laboratory as a valuable 
 chemical reagent in organic chemistry. 
 
 ARSENIC. 
 
 Symbol, As. IIL v - Atomic weight, 75. 
 
 Arsenic is a heavy brittle solid of a dark steel gray 
 color and a metallic lustre. It has two distinct allo- 
 tropic modifications. One is the form just named, and 
 the other is the amorphous variety, of a black color and 
 a vitreous appearance. Arsenic volatilizes without fus- 
 ing at 325° Fah. 
 
 It has been known for centuries. It occurs native 
 and in combination with other elements. Orpiment and 
 realgar are sulphides of arsenic, and mispickle is a union 
 of iron and arsenic. 
 
 Arsenic is obtained by heating mispickle, or some of 
 the sulphides of arsenic in retorts. The arsenic sub- 
 limes and condenses in the cooler portions of the retort. 
 It is also obtained by reducing the oxide by heating it 
 with charcoal. 
 
 Arsenic is used in the arts and pyrotechnics, and in 
 the manufacture of shot and fly paper. 
 
 The common compounds of arsenic are: The hydro- 
 gen arsenide, AsH 3 ; the tri-sulphide, As 2 S 3 , or 
 orpiment ; the oxides and acids of arsenic, As 2 3 , 
 arsenious oxlde, and H 3 As 2 3 , the arsenious acid ; 
 the arsenic oxide, As 2 5 , and the arsenic acid H 3 As0 4 , 
 and potassium arsenide or Fowler's Solution. 
 
 arsenious oxide. 
 
 As 2 3 . Arsenious Acid. 
 Arsenious Oxide, the tri-oxide of arsenic or white 
 arsenic; the arsenic of the shops is a white crystalline, 
 solid, ordinarily, but may also exist in an amorphous, 
 vitreous form. It has a sweetish taste, afterward me- 
 tallic, acrid, and nauseating. It has no odor, is slightly 
 soluble in water — two parts of the crystals will dissolve 
 in 1,000 parts of pure cold water, and 87 parts of the 
 crystals in 1,000 parts of boiling water. The solution 
 made with boiling water may be evaporated until the 
 quantity is reduced about one-half, when 166.6 parts of 
 
arsenic will remain in perfect and permanent solution. 
 Arsenious oxide occurs native as such. It occurs as 
 a by-product where any ores are roasted which contain 
 arsenic. It is so obtained for commercial and other 
 purposes. The oxide sublimes and the first sublimate is 
 purified by re-sublimation. 
 
 Arsenious oxide is a valuable remedial agent, prop- 
 erly used. It is an energetic corrosive poison. 
 
 ANTIMONY. 
 
 Stibium. Symbol Sb'. Atomic weight, 122. 
 
 Antimony is a brittle crystalline solid of a bluish 
 white color, resembling zinc. 
 
 It occurs free in nature, and also in combination, 
 principally with sulphur, to form a tri-sulphide, called 
 stibnite. 
 
 It is obtained by roasting the sulphide and fusing the 
 product with charcoal. 
 
 It is used in the manufacture of type metal and brit- 
 tania. 
 
 The common compounds of antimony are : hydrogen 
 
 ANTIMONIDE, Sl/'TIg, the ANTIMONY CHLORIDE ; Sb^'Cls, 
 
 the butter of antimony, the tri-sulphide, or sulphuret 
 of antimony, and three oxides, the tri- oxide, Sb 2 3 , the 
 pent-oxide, Sb 2 5 , and the tetr-oxide, Sb 2 4 ; tartar 
 emetic is the antimonium and potassium tartrate, 
 (KSbOC 4 H 4 (i ). It is prepared by boiling three parts of 
 the tri-oxide of antimony with four parts of cream of 
 tartar. The mixture is then filtered, the filtrate evaporated 
 and the tartarized antimony crystallizes out. It is of 
 considerable use in pharmacy and medicine, and is an 
 active irritant poison to man. It is corrosive, and a 
 powerful emetic. 
 
 SULPHUR. 
 
 Symbol S. n - IV - VL Atomic weight, 32. 
 Sulphur in its commonest form is a lemon yellow solid; 
 brittle, tasteless, odorless, and crystallizable ; insoluble 
 in water, but soluble in the di-sulphide of carbon. It 
 exists in three allotropic modifications, which include 
 many forms. In the amorphous variety, there is the 
 crude sulphur, and the roll sulphur or brimstone. In 
 the crystalline variety, there is the flowers of sulphur, 
 
and precipitated or milk sulphur, and the last is the 
 plastic form. Sulphur melts at 234° Fah. and boils at 
 824°. It readily sublimes. It is purified by sublim- 
 ation. 
 
 Sulphur was known to the ancients. It is found free 
 in the volcanic regions of Sicily and Italy. As iron 
 pyeites it is found in Sweden, Norway, Spain and 
 Portugal. It is found in all parts of the world com- 
 bined with lead (galena), with zinc (blende), and in 
 the sulphates. It is present in animal and vegetable 
 tissues in considerable quantities. 
 
 The sulphur of commerce is prepared usually from 
 the free native sulphur, by sublimation. If the vapor is 
 received in cold chambers, the product is the dry crystal- 
 line flowers of sulphur ; if in hot chambers the product 
 is in liquid form and is drawn off into moulds and cooled 
 in the form of roll brimstone. 
 
 Sulphur may be separated in the. same manner by 
 heating any of the sulphides above named. Plastic 
 sulphur is prepared by heating melted sulphur to 650° 
 Fah., and then pouring it into cold water. It is soft, 
 plastic, transparent, capable of being moulded like wax. 
 It is not a permanent form, but may change back on 
 exposure, to the yellow crystalline variety. 
 
 Sulphur is used extensively in medicine. It is used 
 in the arts, in the manufacture of sulphuric acid, and in 
 the bleaching of woolen and straw goods. It is used 
 in making matches, and in the manufacture of gun- 
 powder. 
 
 Sulphur unites readily with many elemental substances. 
 The important compounds of sulphur are the mon-oxide 
 (SO); the di-oxide (S0 2 ), and the tri-oxide (S0 8 ). 
 The hydrogen sulphide (H 2 S), the sulphates, and the 
 
 SULPHUR ACIDS. 
 
 SULPHUROUS OXIDE. 
 
 SO % . Anhydride. 
 Sulphurous Oxide, the dioxide of sulphur, is a 
 dense, colorless gas, twice as heavy as air, with the 
 pungent suffocating odor of a burning match. It is 
 quite soluble in water in the proportion of 40 volumes 
 of the gas in one volume of water, forming sulphurous 
 
acid. Dissolved in alcohol it produces a colorless liquid, 
 expansible by heat and very volatile, producing a great 
 degree of cold (-85°) by its volatilization. It is neither 
 combustible, nor a supporter of combustion. It is 
 irrespirable, producing suffocation and exercising a 
 corroding action on the lungs. 
 
 Stahl first described the peculiar character of sulph- 
 urous oxide; but Priestly, in 1774, was the first to 
 carefully examine its properties. It is found abundantly 
 in the exhalations from volcanoes. It is the direct 
 product of the burning of sulphur in the air, or in 
 oxygen, and is thus obtained. 
 
 It is a useful compound. It is a powerfully disin- 
 fectant and antiseptic agent, and is used for that pur- 
 pose. It is a reducing agent, having a great attraction 
 for oxygen. It is used for bleaching, decolorizing and 
 deodorizing purposes. After colors are removed by 
 this agent, they may be restored by the use of weak 
 chlorine water, or an alkaline solution. United with 
 water, the direct chemical product is sulphurous acid. 
 
 HYDROGEN SULPHIDE. 
 
 II^S. Sulphuretted Hydrogen. 
 
 Hydrogen Sulphide is a heavy, colorless gas, with 
 a stinking permanent odor and a disgusting taste. It 
 is slightly acid in its reaction; is not irritating, but is 
 poisonous. A dog will die in an atmosphere containing 
 one part of the gas in 800 of the air. Birds die in one 
 part in 1,000, and a man will die in one per cent, of 
 the gas. It is narcotic in its action and deoxidizes the 
 blood. It is soluble in the proportion of 3.23 volumes 
 of the gas in one volume of water. A pressure of 17 
 atmospheres will reduce it to a colorless liquid. It 
 burns readily. 
 
 Hydrogen Sulphide is the direct product of the de- 
 composition of all animal matter and much vegetable 
 matter. It is a large constituent of sewer gas, and is 
 the cause of much disease in cities. It occurs in the 
 animal body in certain diseases : by the decomposition 
 of albumen in the intestines, in cancerous diseases, in 
 abscesses, in phthisis, and in the bladder in cystitis. 
 
It is used almost only as a re-agent in the laboratory, 
 as its reactions with the metals, producing sulphides, 
 are characteristic and easily distinguishable. 
 
 Its presence in the air may be detected by exposing 
 a white paper wet with a solution of the lead nitrate. 
 The paper becomes blackened. 
 
 THE SULPHUR ACIDS. 
 
 There are many acids formed by the action of water 
 on the sulphur oxides which are very interesting. The 
 common sulphur acids, with a series called the polythi- 
 onic series, or the many sulphur series, from the 
 repetition of the sulphur atoms in the molecule, is the 
 following : 
 
 H 2 S0 2 =Hyposulphurous acid. 
 
 H 2 S0 3 =Sulphurous acid. 
 
 H 2 S0 4 =Sulphuric acid. 
 
 H 2 S 2 3 =Theo-sulphurous acid. 
 
 H 2 S 2 0(i=Di-thionic acid. 
 
 H 2 S 3 6 =Tri-thionic acid. 
 
 Ho S 4 6 =Tetra-thionic acid. 
 
 H 2 S 5 6 =Penta-thionic acid. 
 
 H 2 S.>0 7 =Theo-sulphuric acid. 
 
 By a careful study of this series we may understand 
 how the replacement of the hydrogen in these com- 
 pounds by some other element, will form the many com- 
 pounds known as sulphates, sulphites or hyposulphites. 
 
 HYDROGEN SULPHATE. 
 H^SO^ Sulphuric Acid. 
 
 Hydrogen Sulphate or sulphuric acid, oil of vit- 
 riol, is perhaps the most important of all the acids 
 known. It is a dense, colorless, oily, corrosive acid 
 liquid, with a specific gravity of 1.S5. It has a strong 
 attraction for water, and is used as a drying agent. It 
 unites with water with extreme vigor, producing great 
 heat. There are four varieties of sulphuric acid. 
 
 1st. The commercial oil of vitriol, too impure for 
 chemical or medicinal purposes — used only in manufact- 
 ures. It has a brownish yellow color. 
 
 2nd. The colorless pure acid, just described, marked 
 C. P. — chemically pure. 
 
3rd. The glacial acid, which crystallizes at ordinary 
 temperatures. 
 
 4th. The dilute acid of the pharmacopcea, which 
 contains only 9 or 10 per cent, of the strong acid. 
 
 Su puuric acid was known in the 15th century. It 
 occurs in the natural springs and in some rivers. In the 
 process of its manufacture sulphur is burned in the air, 
 and the product, S0 2 , is conducted into a lead chamber, 
 which contains the higher nitrogen oxides and water 
 vapor. Each molecule of the S0 2 immediately abstracts 
 an atom of oxygen from the nitrogen oxides, and, unit- 
 ing with a molecule of the water vapor, forms the acid. 
 The nitrogen oxides which are reduced by the abstrac- 
 tion of oxygen immediately replace their oxygen from 
 the air. The acid thus quickly formed falls in the water 
 in the bottom of the chamber, which is drawn off when 
 it reaches a specific gravity of 1.45, and is reduced by 
 evaporation to a specific gravity of 1.85, when it is 
 transferred to carboys or tanks for shipment. The re- 
 actions taking place in its formation are the following: 
 S+0 2 =S0 2 +0=S0 3 +H 2 0=H 2 S0 4 . 
 
 Sulphuric acid is the basis of chemical manufacture. 
 It is used in the manufacture of citric, tartaric, and 
 phosphoric acids — in the separation of the alkaloids, in 
 the manufacture of the soda compounds, alum, phos- 
 phorus, and many other chemical and pharmaceutical 
 products. It is used in refining processes; in the puri- 
 fication of petroleum and manufacture of fertilizers; in 
 bleaching and dyeing, and in the manufacture of com- 
 bustibles and explosives. It is used in therapeutics, but is 
 not an important agent. The sulphates, however, which 
 may be formed from it are very important medical agents. 
 
 THEO-SULPHURIC ACID. 
 
 II 2 S 2 0^. Di-SuJphur'tc Acid. 
 Di-Sulphuric Acid, or the Nordhausen Acid, is a 
 dark colored, intensely corrosive, fuming, concentrated 
 heavy acid, having all the properties of the sulphuric 
 acid intensified. It is prepared by the distillation of 
 dried ferrous sulphate in Nordhausen, in Saxony, for the 
 dissolving of indigo in the manufacture of the celebrated 
 Saxony blues. It hisses in water, and is immediately 
 destructive to animal tissues. Its uses are limited. 
 
PHOSPHORUS. 
 
 Symbol P. IIL v - Atomic weight, 31. 
 
 Phosphorus in its ordinary form is a translucent, 
 wax-like, yellow solid ; luminous in the dark, unstable 
 in the air. It is not soluble in water, but dissolves in 
 alcohol, petroleum, ether, and the di-sulphide of carbon. 
 It is violently poisonous, producing its effects by cleoxi- 
 dation of the blood. It melts at 112°, boils at 554°, 
 giving off a colorless vapor. Phosphorus is used in the 
 manufacture of matches. It is an active therapeutic 
 agent, but is too poisonous for common use. The acids 
 of phosphorus and the phosphates and hypophosphites 
 are common restoratives to the osseous and nervous 
 structures of the system. 
 
 Phosphorus may exist in two distinctly different allo- 
 tropic states. The first is the form just described, and 
 the second is the variety known as the red phosphorus. 
 The red variety is insoluble in those solvents which will 
 dissolve the other form. It has no odor, does not oxidize 
 in the air, and is neither luminous nor poisonous. It is 
 prepared by retaining the ordinary variety at a heat of 
 500° for 36 hours. The heat destroys its affinity for 
 oxygen. 
 
 Phosphorus was discovered by Brandt in the product 
 of evaporated urine, in 1669. It does not occur free, 
 but is always found in combination, most often with 
 calcium, sodium and potassium. It is derived from 
 bones in which it exists as the tri-calcium phosphate. 
 
 The ashes of burned bones are mixed with two-thirds 
 their weight of strong sulphuric acid and 20 parts of 
 water. This mixture stands 24 hours. The superna- 
 tant liquid is poured off and evaporated to a syrupy 
 consistency. This is mixed with 20 per cent, of its 
 weight of powdered charcoal and sand, and heated to 
 redness. When dry, the mass is heated in retorts to a 
 white heat, when the phosphorus distills over and is 
 condensed in receivers. The crude product is melted 
 under water, and washed with a mixture of sulphuric 
 acid and potassium bi-chromate for purification. The 
 liquid product is moulded in sticks, in tubes cooled in 
 water. It is kept in water for its proper preservation. 
 
POTASSIUM. 
 
 Kalium. Symbol K. Atomic weight, 39. 
 
 Potassium is a silver white or bluish white, lus- 
 trous metal, which melts at 144° Fab.., the liquid hav- 
 ing a little of the appearance of mercury. It distills at 
 a red heat. It abstracts oxygen with great facility from 
 the atmosphere and thus tarnishes quickly. It acts upon 
 water, abstracting the oxygen and setting the hydrogen 
 free, which may burn in the intense heat produced in 
 its liberation. 
 
 It is found in its compounds in various parts of the 
 earth. It exists in animal and vegetable structures, in 
 the soil and rocks and in the sea. It does not occur 
 free. It was obtained free first by Sir Humphrey Davy, 
 in 1807. It is obtained in the lye from a solution of 
 wood ashes, and the hydrate, in this form, has been long 
 used in making soap. 
 
 It is prepared by heating together the potassium car- 
 bonate and carbon. This, heated to a white heat with 
 the potassium tartrate, drives off the free potassium by 
 distillation, and is received and condensed under naph- 
 tha. The process is difficult and dangerous. 
 
 Its uses in its elemental state are limited, but it unites 
 readily with many elements, forming the long list of po- 
 tassium compounds which are of more or less import- 
 ance in chemistry, in medicine and in the arts. 
 
 The important compounds are its compounds with the 
 halogens and the potassium hydrate, carbonate, nitrate, 
 sulphate, and chromates. 
 
 SODIUM. 
 
 Natrium. Symbol Na. r - IIL Atomic weight, 23. 
 
 Sodium resembles potassium in appearance. It is a 
 soft, silver-white metal, lustrous and easily tarnished. 
 It melts at 204° Fah., and volatilizes at a white heat, the 
 vapor burning with a bright yellow flame. It abstracts 
 oxygen from water, liberating the hydrogen, but not as 
 actively as potassium. 
 
 Davy obtained the metal free in 1807. In its com- 
 pounds it is most abundant. It occurs in sea and rock 
 salt, in borax, in nitrate of soda and in the carbonate 
 and silicates. It is essential to all animal life. 
 
It is prepared in the same manner as potassium, from 
 its carbonate. 
 
 In its elemental form its use is limited to metallurgy. 
 In its compounds, it is of extended importance in medi- 
 cine, in arts and in manufactures. 
 
 The important compounds of sodium are its halogen 
 compounds, its carbonate, sulphate, hydrate, phosphate, 
 and nitrate, and sulphite and hyposulphite. 
 
 CALCIUM, 
 
 Symbol Ca. UIV - Atomic weight, 4-0. 
 
 Calcium is a brilliant light yellow, malleable and 
 ductile metal, of the hardness of gold. It fuses at a 
 red heat, and burns readily with a brilliant reddish-yel- 
 low flame. It is permanent in dry air, but oxidizes 
 quickly in moist air. 
 
 It was obtained pure first in 1855 ; but its charac- 
 ter was known to Davy in 1810. In its compounds it is 
 a very widely distributed and an important element. All 
 limestone, chalk and marble are calcium carbonate, and 
 gypsum is calcium sulphate. 
 
 It is prepared from fusing the calcium chloride or 
 iodide with sodium or zinc, or by acting upon the melted 
 chloride with electricity. Its important compounds are 
 the calcium oxide, hydrate, chloride, sulphate, carbon- 
 ate, phosphate and silicate. 
 
 Its salts are very important in the animal economy. 
 The phosphates are abundant in the bones and teeth, in 
 the nervous structure, and, in fact, in every tissue and 
 solid of the body. The phosphates remain in solution in 
 the body fluids, unless those fluids become alkaline when 
 they are precipitated in a white crystalline form. Alka- 
 line urine is turbid, because the phosphates and carbon- 
 ates of the lime are precipitated. The compounds of 
 calcium are nearly all important therapeutic agents. 
 They are of extended use in the manufactures and in the 
 arts. 
 
 MAGNESIUM. 
 
 Symbol Mg. 11 - Atomic weight, 2 J/,. 
 Magnesium is a tenacious, ductile, brilliant, silver- 
 white metal with a specific gravity of 1.75. It melts at 
 a low red heat, and distills at a white heat. It is per- 
 
manent in dry air, but will readily tarnish in moist air. 
 It burns with a bluish-white, brilliant light. 
 
 Magnesium is abundant in nature, but always in its 
 compounds. It is obtained free by acting upon the 
 fused chloride with electricity; and by fusing the chlor- 
 ides of sodium and magnesium with sodium; afterward 
 purified by distillation in hydrogen gas. 
 
 The elemental magnesium is used to produce brilliant 
 lights, mainly for photographic purposes. The com- 
 pounds are important remedial agents, and are present 
 in animal and vegetable structures. 
 
 ALUMINUM. 
 
 Symbol Al. n - Atomic weight, 27.5. 
 
 Aluminum is a brilliant, silver-white metal ; mal- 
 leable and ductile, susceptible of a high degree of polish. 
 It does not readily tarnish in the air. It is similar to 
 silver in many of its properties. Wohler first obtained 
 the metal free in 1828. 
 
 Aluminum is most widely distributed in nature. It 
 occurs in mica, feldspar, slate, clays, and in crystalline 
 rocks. 
 
 It occurs in emery, in the ruby and sapphire. The 
 process of its separation has recently been simplified, and, 
 because of that fact, it is coming into very general use. 
 
 It is obtained by melting the chloride or the double 
 chloride of sodium and aluminum in a verbratory fur- 
 nace. It is also obtained from other aluminum com- 
 pounds. 
 
 It is used in the arts where silver and nickel are used. 
 It is only inferior to the first; and highly superior to the 
 latter. Some of its compounds are of use in medicine. 
 
 IRON. 
 
 JBerrmn. Symbol Fe. ll - IV - VI - Atomic weight, 56. 
 
 Iron is an element of the utmost utility to man. 
 When pure, it is a soft, brilliant, silvery- white, crystal- 
 line metal ; the most tenacious of all metals ; malleable 
 and ductile. In dry air it is not affected, but oxidizes 
 quickly in the presence of moisture. At a bright-red 
 heat it will decompose water, forming the ferroso ferric 
 oxide and setting the hydrogen free. 
 
It has been known during the history of man. It is 
 iound free in some meteorites, but is commonest in vari- 
 ous ores from which it is easily separated by heat. 
 
 Its principal ores are the iron pyrites, micaceous or 
 clay ores, oxides, carbonates, sulphates, arsenates, phos- 
 phates and oxylates. 
 
 The processes of its separation from its ores by heat 
 are not complex, and are carried on, on a very extensive 
 scale in many countries. 
 
 Iron is the most common of all the metals. In man- 
 ufacture, and in the arts, it is indispensable. In chem- 
 istry, pharmacy and in medicine it is of great value. 
 
 The chemical compounds of iron, most useful to the 
 physician, are the chlorides, the oxides, the hydrates, 
 the carbonates and the sulphates. 
 
 LEAD. 
 
 Plumbum. Ph. lliy - Atomic weight, 207. 
 
 Lead is brilliant, bluish-white, very soft and malle- 
 able. It fuses at a low heat, and is slightly volatile. It 
 tarnishes very quickly in the air, and when heated oxi- 
 dizes rapidly. 
 
 Lead has been known for ages. It occurs in mines in 
 England, Spain, America, and other countries. It is 
 prepared from galena or the sulphide of lead by roast- 
 ing the ore in a reverberatory furnace. 
 
 It is widely used in manufactures and in the arts. Its 
 use in medicine and chemistry are limited but important. 
 Its compounds in any quantity in the animal economy 
 are slowly poisonous. The common compounds are the 
 man oxide, the tetroxide, the dioxide, the chlorides, 
 iodides, nitrates, sulphates, and carbonates; the sul- 
 phide, the acetate, and the chromate. 
 
 COPPER. 
 
 Cuprum. Symbol Cu. n - 1Y - Atomic weight, 63.5. 
 
 Copper is a peculiar, reddish appearing metal— soft, 
 ductile, and tenacious. It does not easily change in the 
 air. It melts at 2200°, and is volatile. 
 
 Copper has been long known. It was obtained by the 
 Romans from Cyprus. It is now obtained from Sweden, 
 China, Japan, and the Ural Mountains, but the largest 
 
mines in the world are on Lake Superior. It is found 
 free and in combination with various substances. The 
 methods of its separation are similar to those of iron and 
 lead. 
 
 Copper is extensively used in manufacture. It is used 
 largely in alloy with zinc, tin, or nickel. It is used in 
 chemistry and in medicine. Its common compounds are 
 the chlorides, iodides, oxides, the sulphate, carbonate, 
 
 ZINC. 
 
 Symbol Zn. "■ Atomic weight, 65 
 
 Zinc is a highly crystalline, bluish-white metal, not 
 strongly cohesive. It is pulverizable at a temperature 
 of 300° Fah; it is malleable and ductile, being easily 
 rolled into sheets. It melts at 800° and volatilizes at 
 1800°. It dissolves readily in dilute acids, decomposing 
 them and liberating their hydrogen. 
 
 The ancient Greeks used zinc abundantly in manu- 
 facturing brass. It is now found in various parts of the 
 world. Its ores are calamine (silicate), blende (sulphide), 
 and smithsonite (carbonate). 
 
 In its preparation the ore is heated in the air and the 
 zinc oxidized. The oxide is heated to a white heat with 
 charcoal, and the free zinc is distilled in proper re- 
 ceivers. 
 
 It is used extensively in architecture and to coat iron, 
 because it does not easily oxidize. It is used as an ele- 
 ment in the generation of electricity, and forms valua- 
 ble alloys with copper, tin, and nickel. It has a limited 
 use in medicine. Its common compounds are the 
 oxide, carbonate, and sulphate. 
 
 NICKEL. 
 
 Symbol Ni. IL IV< Atomic weight, 59. 
 
 Nickel is a pure, lustrous, silver-white malleable and 
 ductile metal. It does not readily fuse, and is very te- 
 nacious. It oxidizes in the air. 
 
 It was discovered in 1751. It is obtained from the 
 arsenide called Kupfernickel. It is difficult of separa- 
 tion. It may be prepared from the oxalate or carbonate 
 by fusing them with hydrogen gas. 
 
Nickel is used for coin and for making German silver, 
 in which it is alloyed with copper and zinc. 
 
 Its common compounds are the hydrate, chloride, sul- 
 phate, oxide, and cyanide. 
 
 Cobalt is closely allied to nickel, and is separated 
 from its ores in the same manner. It has the same ap- 
 pearance and the same atomic weight. 
 
 TIN. 
 
 Stannum Sn. ll - lY - Atomic weight, 118. 
 
 Tin is a soft, white, crystallizable metal. It is not 
 very tenacious or ductile, but quite malleable. It melts 
 at 450 o Fah. Is not volatile. 
 
 It was well known to the Ancients, and is mentioned 
 in the Bible. Homer speaks of it, and Herodotus, 
 because of the large quantities of it in the British Is- 
 lands, called them the tin islands. 
 
 It occurs native and also in combination. It is pre- 
 pared for commerce similar to iron or lead. 
 
 It is used extensively in the arts and in manufacture. 
 It is alloyed with lead, copper, antimony and bismuth 
 to form pewter, britannia, bell metal, gun metal, bronze, 
 etc. It is not used in medicine. Its compounds are the 
 chlorides, oxides and sulphides. 
 
 SILVER. 
 
 Argentwm Ag. L IIL Atomic weight, 108. 
 
 Silver is a beautifully brilliant white metal, soft, yet 
 harder than gold, with considerable tenacity, both 
 malleable and ductile. It is an excellent conductor of 
 both heat and electricity — perhaps the best known. It 
 fuses at a high temperature, and is slightly volatile. It 
 is not changed in the air at any temperature. 
 
 It was well known to the Ancients. It occurs in its 
 elemental form, and also in combination with sulphur, 
 arsenic, antimony, copper and the halogens. It is found 
 in South America, in Mexico, in the United States, in 
 Hungary and Saxony. 
 
 Silver is used in the arts, and its salts in medicine. 
 Alloyed with ten per cent, of copper, it forms coin 
 ' silver. It is too soft to be used alone. 
 
 Its compounds are the oxides, chlorides, Iromide and 
 ?, nitrate and 
 
GOLD. 
 
 Aurum Au. I,m - Atomic weight, 196.6. 
 
 Gold is an exceedingly brilliant, soft, orange-yellow 
 metal. It is highly ductile, and extremely malleable. 
 It is a good conductor of heat and electricity. It is 
 permanent, unaffected by any single concentrated acid 
 (insoluble). Hydrochloric and nitric acids combined 
 (Aqua Regia) contain nascent chlorine, which, when the 
 combined acids are brought in contact with gold, will 
 act upon it, forming a solution of the chloride of gold. 
 
 Gold is widely, although sparingly distributed over 
 the earth's surface. It is found in strata of quartz, and 
 in the alluvial sand from the disintegration of quartz 
 rock It is easily extracted by quicksilver, which is 
 driven off by distillation. 
 
 Gold and silver, because of their intrinsic value, are 
 used in the coinage of all nations. Gold is used for 
 jewelry. It is too soft to be used alone, but is combined 
 with silver and copper in alloy. Pure gold is said to be 
 24 carats fine. Twenty-four parts of the alloy is said to 
 be 1 J:, 18 or 20 carats fine, as it contains that many parts 
 of pure gold and the remainder alloy. 
 
 Gold is of no use in medicine uncombined. Its 
 chloride, however, is a valuable therapeutic agent. 
 
 The compounds of gold are the oxides and the chlor- 
 ides, and the compound chloride of gold and sodium. 
 
 PLATINUM. 
 
 Symbol Ft. n - IV - Atomic weight, 198. 
 
 Platinum is a rare, lustrous, silver-white metal; 
 malleable, ductile, and very tenacious. It must be 
 subjected to an intense heat (3218° Fah.) before fusing. 
 It is not affected by the air or oxygen. It is a poor 
 conductor of heat and electricity. Platinum possesses 
 the peculiar property of condensing gases on its sur- 
 face. In the form of a powder it will absorb 800 vol- 
 umes of oxygen, and alcohol poured upon this alloy is 
 spontaneously inflamed. 
 
 Platinum exists in union with other elements and very 
 rarely in a free state. It is found in North and South 
 America, in Russia and Borneo. 
 
Platinum is used for making chemical vessels, because 
 acids and powerful chemicals do not act upon it. It is 
 used in the coinage of Eussia. Its only important com- 
 pound is the tetrachloride (PtCL,). 
 
 BISMUTH. 
 
 * Symbol Bi. IIL v - Atomic weight, 210. 
 
 Bismuth is a hard, brilliant metal with a bronze 
 tint, quite brittle. It is not changed in the air, takes 
 lire in a strong heat, and burns readily with a peculiar 
 bluish-white flame. It has been known for 400 years. 
 It occurs in the elemental form, and also as the sulphide 
 oxide, and carbonate. The pure bismuth may be ob- 
 tained by heating the nitrate with charcoal. 
 
 Bismuth is used in the arts to form alloys, but the 
 compounds only are used in medicine. 
 
 The compounds are, the chloride (BiCl 3 ), the oxides 
 (Bi 2 5 and Bi 2 O s ), and the hydrate (Bi(HO) 3 ), nitrate 
 (Bi(N0 3 ) 8 , sulphate (Bi 2 (S0 4 ) 3 , carbonate and phosphate 
 Bi(P0 4 ). Bismuth subnitrate is not a definite compound 
 but rather a mixture. 
 
 MERCURY. 
 
 Symbol Hg. n . Quicksilver. Atomic weight, 200. 
 
 Mercury is a liquid metal of a brilliant, silver- white 
 color. It is volatile at a comparatively low tempera- 
 ture. It boils at 680° Fah. , and freezes at —40°. It has 
 only one atom in its molecule. It will form an amalgam, 
 as its alloys are called, with all metals except iron. 
 
 It has been well known for centuries, and is frequently 
 mentioned by ancient writers. It occurs free in consid- 
 erable quantities. It is found most abundantly in com- 
 bination with sulphur as a sulphide (cinnibar). It is so 
 found in Spain, in Austria and in California. The ore 
 is heated in proper vessels, and the volatile product is 
 conducted through cooled pipes or into a cooled cham- 
 ber, where it condenses. Elemental mercury is of but 
 little use in medicine. 
 
 It is used for extracting gold and silver ores; and for 
 amalgams. Its amalgam with tin is the common coating 
 for mirrors. It is used in filling thermometers and in 
 barometers, because of its susceptibility to changes of 
 
temperature, and the wide range between its freezing 
 and boiling points. 
 
 Its compounds, the chlorides and iodides, oxides and 
 sulphates, are of use in medicine and surgery. All the 
 salts of mercury are poisonous. 
 
 MERCUROUS AND MERCURIC CHLORIDES. 
 
 (Eg CI.),. HgCk. 
 
 The Mild Chloride of Mercury, known as Calo- 
 mel, the mercurous chloride, is a heavy white powder, in- 
 soluble in water. It volatilizes at a low heat, and crystal- 
 lizes in minute characteristic crystals. It is used quite ex- 
 tensively in medicine. In sufficient doses it is poisonous. 
 
 Corrosive Sublimate, the mercuric chloride or the 
 corrosive chloride, contains double the amount of chlorine 
 as the mild chloride, and is a powerful corrosive poison. 
 
 It is soluble in both cold and hot water. It is pre- 
 pared by distilling a mixture of common salt (NaCl) and 
 the sulphate of mercury (HgS0 4 ). HgS0 4 +(NaCl) 2 = 
 Na 2 S0 4 +HgCl 2 . Both the chlorides produce character- 
 istic chemical reactions. 
 
 Mercuric Iodide, Hgl 2 is a crystalline powder of a 
 brilliant scarlet red color. It may be prepared by 
 adding a solution of potassium iodide to a solution of a 
 mercuric salt. It is volatile at a low heat. It has a 
 limited use in medicine. 
 
 Mercurous Iodide (Hgl) 2 has a more limited use 
 even than the above. It is a greenish-yellow crystalline 
 substance, and may be precipitated by acting upon a 
 solution of any mercurous salt with iodine. 
 
 ORGANIC CHEMISTRY. 
 
 Chapter III. 
 
 CARBON. 
 
 Symbol C. IV - Atomic weight, 12. 
 Carbon is one of the commonest of the elements. In 
 the air at ordinary temperature, it is a permanent solid ; 
 insoluble in all menstrua. It does not melt or volatalize. 
 It occurs free in three distinct allotropic forms — the 
 diamond, graphite and amorphous carbon. 
 
The Diamond is the hardest substance known. 
 It is pure crystalline carbon, occurring in brilliant octa 
 hedral crystals, usually colorless or yellowish — some- 
 times blue, green, pink, brown or black. It is a poor 
 conductor of heat and electricity. Heated intensely in 
 a vacuum, it is converted into coke. It possesses a high 
 power of refraction. 
 
 Graphite is almost as pure carbon as the diamond. 
 It is crystalline, of a dark gray color and a soft soapy 
 feel. It does not burn readily, nor volatilize. It is the 
 plumbago or black lead of commerce, and is used in the 
 manufacture of lead pencils. 
 
 There are several forms of amorphous carbon, both 
 natural and artificial. The commonest of the natural 
 forms is coal, the hardest of which, anthracite coal, may 
 contain from 95 to 98 per cent, of carbon, but com- 
 monly only from 80 to 90 per cent. The softer, or 
 bituminous coal, ranges from cannel coal and jet down 
 through several stages of decreasing hardness to the 
 brown coal, lignite or wood coal. 
 
 Of the artificial forms of amorphous carbon, the soot 
 or lamp black, is quite pure carbon, and is prepared by 
 the imperfect combustion of pitch, tarry substances or 
 turpentine. 
 
 It is used as a pigment. 
 
 Charcoal is obtained by burning wood with an insuffici- 
 ent supply of oxygen. It condenses gases and odorous sub ■ 
 stances within its pores, and is thus an active disinfecting 
 agent. It is used to prevent putrefaction and as a filtering 
 agent, and also in the manufacture of gunpowder. 
 
 Animal Charcoal is obtained by the incomplete com- 
 bustion of animal substances, conducted in closed vessels. 
 Bone black is made from bones, and ivory black from 
 ivory. Bone black possesses a greater power of absorb- 
 ing the coloring matter and putrid odor of substances 
 filtered through it than wood charcoal. 
 
 By treating bone black with dilute hydrochloric acid, 
 the calcium phosphate which it contains is removed, and 
 the product is the carbo animalis purijicatus. 
 
 Coke is the cinder, or porous, hard, grayish substance 
 which remains in gas retorts after the destructive distil 
 lation of coal in the manufacture of illuminating gas. 
 
When iron retorts are used, there is deposited upon 
 their walls a layer of hard, compact, grayish carbon, 
 called gas retort carbon, which is an excellent conductor 
 of electricity, and is used for the carbons or negative 
 plates of galvanic batteries and for electric light points. 
 
 CARBON MON OXIDE. 
 
 CO. Carbonous Oxide. 
 
 Carbon Mon Oxide is a colorless, tasteless gas, 
 sparingly soluble in water and in alcohol. In the air it 
 burns with oxygen, with a blue flame, producing the 
 higher oxide of carbon, C0 2 . It is unstable in its chem- 
 ical composition, the carbon being better satisfied in its 
 highest equivalence. 
 
 It is formed in any imperfect combustion where carbon 
 is burned in an insufficient supply of oxygen. It may 
 also be formed by passing the carbonic acid gas, C0 2 , 
 over red hot charcoal, when it loses half of its oxygen. 
 
 Carbonous oxide is a poisonous gas. Being given off 
 readily from air tight hard-coal stoves and furnaces, and 
 in the burning of illuminating gas, it is a common cause 
 of vitiated atmosphere in tight rooms. 
 
 Blast furnaces give off from 20 to 30 per cent, of 
 this gas. One part of the gas in 200 of air will kill 
 birds and small animals in a short time. Ordinary 
 illuminating gas contains from 4 to 7 per cent, of this 
 gas. A small quantity in a room produces languor, 
 headache and debility. When inhaled it changes the 
 character of the blood, preventing the corpuscles from 
 carrying ©xygen to the tissues. Its effects are quite 
 permanent. 
 
 CARBON DI OXIDE. 
 
 C0 2 . Carbonic Acid Gas. 
 Carbon Di Oxide is the direct product of the burn- 
 ing of carbon in the air. It may be produced also by 
 the decomposition of the carbonates with hydrochloric 
 or other mineral acids. It is a heavy, colorless, suffo- 
 cating gas, with an acid taste. It neither burns nor 
 supports combustion. It is soluble in equal volumes of 
 water, at ordinary atmospheric pressure. Its solubility 
 increases with increased pressure ; one volume for each 
 additional atmosphere. Soda water is a solution of the 
 
gas in water under pressure. The gas may be reduced 
 by the pressure of 38 atmospheres, at the freezing point 
 of water, to a colorless liquid, which will evaporate on 
 the removal of the pressure so rapidly as to freeze its 
 own vapor. It does not burn or support combustion. 
 
 This gas is an important permanent constituent of 
 the atmosphere, in the proportion of about 4 parts in 
 10,000. It is exhaled by man and animals, and is the 
 product of all combustions and most decompositions of 
 organic matter. It is absorbed by all vegetation, and 
 is thus the source of the supply of carbon. Its absorp- 
 tion takes place only by the influence of sunlight, there- 
 fore there is a larger proportion found in the fields in 
 the night than during the day. There is a larger pro- 
 portion in the air of cities, because of the large quantity 
 of carbon burned and the absence of vegetation to 
 absorb the gas. It is estimated that a man 25 years old 
 exhales about 550 quarts of the gas in 24 hours. If air 
 contains more than 7 parts in 10,000 it is contaminated. 
 If the gas is added to the air of a room without being 
 formed in the air, the contamination is not so serious as 
 when it is produced in the room by the combustion of 
 the oxygen from the atmosphere of the room. In the 
 latter case, the noxious gas is not only added to the 
 atmosphere, but it is added at the expense of the oxygen 
 of the same space. 
 
 An animal will die quickly in a room containing one- 
 fifth its volume of C0 2 if the gas was formed from the 
 oxygen in the room, reducing the oxygen two parts per 
 hundred of the atmosphere. But if there is more than 
 the normal quantity of oxygen in the room, from 35 to 
 40 parts per hundred, an animal will live a long time in 
 a larger quantity of the gas. The poisonous effects of 
 the gas are vertigo, drowsiness, headache, irritation in 
 the larynx, increasing muscular weakness, and death 
 from coma. 
 
 The treatment of poisoning from carbonic acid gas 
 consists in stimulation, artificial respiration, oxygen 
 inhalations, electricity and friction. 
 
 Carbon possesses to a greater degree than any other 
 element the power of saturating its own equivalences. Be- 
 cause of this fact, there are a great many compounds of 
 
carbon or organic substances. In the study of inor- 
 ganic substances we have many compounds made up of 
 many of the elements. There are many more organic 
 substances than inorganic; but they are all made up of 
 carbon, united with only a few other elements, princi- 
 pally oxygen, hydrogen, and nitrogen, with different 
 proportions of carbon. The change in the character of 
 the molecules depends, not on a change in the kind of 
 atoms, but on a change in the number of atoms, and in 
 their relative position. 
 
 ALCOHOL. 
 
 (C. 2 & 5 )HO. Ethyl Hydrate. 
 
 Vinic Alcohol, spirit of wine, ethylic alcohol, is a 
 light, colorless, transparent, volatile liquid, with a sharp 
 irritating taste and a spirituous odor. It is lighter than 
 Avater, its specific gravity being only 0.80. It boils at 
 173° Fah., and has never been frozen. It has a great 
 affinity for water, mixing with it in all proportions. 
 
 It attracts water from the air. It is an excellent 
 solvent, dissolving many substances insoluble in water. 
 Medicinal substances dissolved in alcohol are called 
 tinctures. Gaseous and volatile substances so dissolved 
 are called spirits. 
 
 Fermentation is a decomposition, produced in the 
 processes of the nutrition of certain low forms of ani- 
 mal or vegetable life. The common ferments are the 
 torula cerevisce, which produces alcoholic fermentation; 
 the penicillium glcmcum, which produces lactic acid 
 fermentation, and mycoderma acetic, which produces 
 acetic acid fermentation or vinegar. 
 
 Alcohol is the product of the fermentation of certain 
 organic vegetable substances which contain sugar or 
 starch; rye, barley, corn, rice, potatoes, the juices of 
 certain fruits, and molasses, are fermented in the manu- 
 facture of whisky, brandy, beer, ale, wines, rum, etc. 
 
 Alcohol occurs in different strengths. 
 
 Absolute alcohol is the pure alcohol without water or 
 other foreign substance. It is rarely obtained. That 
 which is purchased for absolute alcohol contains at least 
 2 per cent, of water. Alcohol U. S. P. contains 94 per 
 cent, of the absolute. 
 
It has a specific gravity of 0.82 The rectified spirit 
 of wine, spiritus. rectificatus Br. P., contains 84 per cent, 
 of absolute alcohol. 
 
 Dilute alcohol, alcohol dilutum, U. S. P., contains 54 
 per cent of the absolute. This is about the same as the 
 proof spirit of commerce. 
 
 Alcohol in sufficient doses is a powerful irritant poison. 
 It abstracts water from the tissues and coagulates their 
 albumenoids. Undiluted, it may produce immediate 
 death. Diluted, its use may be prolonged; the poison- 
 ous effects slowly appearing as its use is persisted in. 
 
 It is an active stimulant, and produces temporary activ- 
 ity of all the body functions, followed by a correspond- 
 ing stage of depression. 
 
 ACETIC ACID. 
 C 2 E 4 2 . Pijroligneous Acid. 
 
 Acetic Acid. Acetyl hydrate, or the hydrogen ace- 
 tate, is a colorless, mobile liquid, with a pungent odor, 
 and a sharp characteristic acid taste. When pure, it 
 crystallizes at 62.6° Fah., and boils at 246°. Its spe- 
 cific gravity is 1.08, at the freezing point of water. It 
 mixes readily with water. It produces vesication and 
 corrosive action on animal tissues. 
 
 Acetic acid is produced by the destructive distillation 
 of wood. The crude pyroligneous acid of commerce 
 contains four per cent, of acetic acid and twenty per 
 cent, of oily and tarry substances. This is distilled, 
 and the distillate is acted upon in a complex process, by 
 slacked lime, and the after product by sulphuric acid. 
 The acetic acid is finally separated by distillation. 
 
 The ordinary liquid acetic acid, U. S. P., contains 36 
 per cent, of the pure acid dissolved in water. The pure, 
 free acid is known as the glacial acetic acid. Acetic 
 acid, in sufficient doses, is a corrosive poison. 
 
 Vinegar is a liquid, acidulated with acetic acid ; 
 produced therein by the ferment my coder ma aceti in the 
 natural process of acetous fermentation. Alcoholic fer- 
 mentation first takes place in the fermenting substance, 
 and this is followed by the acetous fermentation, pro- 
 duced artificially by the introduction of the character- 
 istic ferment, or mother of vinegar. 
 
Vinegar is made from cider, wine and beer. It is 
 necessary to add a small quantity of alcohol often dur- 
 ing the fermenting process. 
 
 ETHER. 
 
 ( C 2 H^2 0. Sulphuric Ether. 
 
 Sulphuric Ether, the ethyl oxide, or ethylic ether, 
 is a light, limpid, transparent, colorless liquid, with an 
 intense unpleasant odor, and a sharp, acid, burning taste. 
 
 Its specific gravity is 0-72, and its boiling point is 
 only 94° Fah. It crystallizes at — 24° Fah. It is exceed- 
 ingly volatile, and its vapor is highly inflammable and ex- 
 plosive, mixed with air. It is soluble in water, and in 
 alcohol. It is an excellent solvent of many substances, 
 some not otherwise dissolved. 
 
 Ether is made by the decomposition of alcohol with 
 sulphuric acid. Five parts of the alcohol and nine parts 
 of strong sulphuric acid are mixed in a vessel in a cold- 
 water bath. This mixture, with a small stream of 
 alcohol, is conducted into a retort heated in a sand-bath 
 to 280° Fah. The chemical processes are such, that 
 the sulphuric acid acts upon the alcohol, forming sul- 
 phovinic acid and water. This newly formed organic 
 acid, in its turn, acts upon another molecule of alcohol, 
 forming ether and sulphuric acid. The following is the 
 reaction which occurs: C 2 H 6 0+HoS0 4 =(C 2 H 6 )"S0 4 + 
 H 2 0. (C,H 6 )"S0 4 +C 2 H 6 0=fC 2 H 5 ) 2 0+H,S0 4 . 
 
 Ether is a common and comparatively safe general 
 anaesthetic. It produces local anaesthesia, also, by the 
 abstraction of heat. Internally, it is an active poison, 
 although less so than chloroform. Death occurring 
 more slowly, there is time for the administration of 
 restoratives. 
 
 Artificial respiration, and the application of electricity 
 to the spinal centers and to the respiratory muscles, are 
 the available means of restoration. 
 
 CHLOROFORM. 
 
 CHCl z . Dichloromethyl Chloride. 
 
 Chloroform, formyl chloride, trichloromethane, is 
 
 formed by the saturation of a common organic radical 
 
 (CH)"' with chlorine. This is a derivative of the first 
 
 of the paraffine series of hydro carbons; and the same 
 
radical similarly saturated with each of the halogens 
 forms compounds similar in their construction to chloro- 
 form, forming respectively jluroform, hromoform, and 
 iodoform. 
 
 Chloroform is a heavy, colorless, volatile liquid, with 
 a pleasant etherial odor, and a sharp, pungent, sweet 
 taste — soluble in alcohol and ether, but sparingly solu- 
 ble in water. 
 
 It will dissolve fats, resins, gutta-percha, certain alka- 
 loids, phosphorus, iodine, and other substances insoluble 
 in water or other solvents. 
 
 It is stable in the light. 
 
 It is prepared by heating together recently slacked 
 lime, chloride of lime, and water, to which alcohol is 
 added, and the temperature quickly raised. When the 
 chloroform begins to distill over, the fire is withdrawn. 
 The crude distillate is purified by exposure to sulphuric 
 acid, and mixing this with alcohol and potassium car- 
 bonate, and again distilling. 
 
 Chloroform, taken internally in sufficient quantity, is 
 an irritant poison. Being insoluble and easily diffus- 
 ible, it produces intense local effects rapidly. 
 
 Inhaled, it acts more quickly than other anaesthetics. 
 It paralyzes the nerve centers, and thus immediately in- 
 terferes with the functional workings of the important 
 organs of the body, especially the heart. 
 
 It produces more satisfactory results as an anaesthetic 
 than ether, but, because of its speedy action, is more 
 dangerous. 
 
 There is no known antidote to chloroform. The 
 patient may be quickly inverted. Nitrate of amyl, am- 
 monia, hypodermic injections of nitro glycerine, and 
 electricity, have all been beneficial, and all have failed. 
 
 IODOFORM. 
 
 CH1 Z . Di-iodomethyl Iodide. 
 Iodoform, formyl iodide, tri-iodomethane, is a yellow 
 crystalline solid, with a permanent penetrating odor and 
 a sweetish taste. 96.7 per cent, of its weight is iodine. 
 It sublimes, is insoluble in water and in the stronger 
 acids and alkalies ; soluble in alcohol, ether, and in the 
 
essential oils and in the disulphide of carbon. It is pre- 
 pared in much the same manner as chloroform. 
 
 It is an active disinfectant and antiseptic, and is of 
 extensive use in surgery. It is also given internally for 
 gastric and intestinal disorders, with decomposition, or 
 where an active antiseptic is needed. It may be given 
 also in those cases where iodine is indicated. 
 
 GLYCERIN. 
 
 C z R 5 {IIO) z 
 
 Glycerin is a syrupy liquid, colorless, odorless, with 
 a sharp sweetish taste. Its specific gravity is 1.26. 
 It is not crystallizable or easily volatile (crystals some- 
 times form in glycerin, but the circumstances of their 
 formation is not understood). It is soluble in water 
 and in alcohol, and is itself a good solvent for many 
 organic substances. 
 
 Glycerin exists free in a number of vegetable oils. 
 It occurs in alcoholic fermentation, and as a bi-product 
 in the manufacture of stearin candles and soaps. It is 
 prepared by the distillation in superheated steam of the 
 product of the decomposition of neutral fats. 
 
 Pure glycerin is valuable in medicine, It is a nu- 
 trient, and will supply the place of cod liver oil with 
 children. 
 
 It is an antiseptic, and will prevent decomposition of 
 food in the stomach and the consequent eructations of 
 gas. It is valuable as an external application to bruises 
 and abrasions of the skin and mucous membranes. 
 
 CARBOLIC ACID 
 
 C 6 R 6 O. Phenol. 
 
 Carbolic Acid, phenol, phenic acid, hydrogen phe- 
 nate is a crystalline solid with a peculiar, not unpleasant 
 odor, and an acrid, caustic taste. 
 
 It melts at 95° Fah. and boils at 370° Fah. It liquifies 
 by the addition of about five per cent, of water at ordin- 
 ary temperatures. It is not readily soluble in water, 
 but is soluble in ether and in alcohol. It will not distill 
 without decomposition. 
 
 Carbolic acid is a coal tar product. In the distillation 
 of coal tar, the distillate between 300° and 392° Fah. is 
 treated with a solution of potassium hydrate. The 
 
crystalline product of this reaction is dissolved in hot 
 water, and, becoming cool, the liquid separates in two 
 layers. The heavier layer is neutralized with hydro- 
 chloric acid ; the phenol separates ; is washed, dried 
 with calcium chloride, and redistilled. The product of 
 this redistillation is the crystalline carbolic acid. 
 
 Carbolic acid is a powerful antiseptic. In contact 
 with animal tissues, it produces a characteristic white 
 discoloration and a cicatricial like contraction, and is an 
 anaesthetic. It coagulates albumen. Taken internally 
 in sufficient quantity, it is an energetic poison. It may 
 be detected by the odor and by the white appearance 
 of the membranes. If egg albumen be taken immedi- 
 ately after the taking of carbolic acid, the excess of 
 acid will unite with the albumen to form an insoluble 
 albumenoid. In small doses, it is used as a medicine 
 in cases where an antiseptic is needed, with decided 
 beneficial effects. It also stimulates digestion and pro- 
 motes the functions of the stomach in some cases of 
 dyspepsia with fermentation. 
 
 It is not as extensively used in surgery as formerly, 
 although it is of extreme value as a surgical dressing. 
 
 ANALYTIC AL CH EMISTRY. 
 
 Chapter IV. 
 
 The Laboratory Course in a medical college, be- 
 cause of the limited time the student has to devote to it, 
 is confined to a very limited portion of the entire work 
 of analytical chemistry. It is confined to the study of 
 simple water analysis, of a few reliable tests for common 
 poisons and deleterious substances, whose presence is 
 detrimental to health ; and to the analysis of urine, and 
 perhaps other body fluids and excretory products. 
 A thorough chemical course, however, is of great 
 advantage. 
 
 It is necessary also to precede the study of the tests, 
 etc., by a short study of the laboratory apparatus, and 
 manipulation or laboratory technics. 
 
 Apparatus. — An alcohol lamp, an evaporating dish, 
 a blow pipe, test tubes, tube rack, beaker-glass, glass- 
 
tubing, glass rods, watch glasses, platinum foil, a fun- 
 nel, wash bottles, a tube brush, and filter-paper. 
 
 A Solvent is the liquid which dissolves another sub- 
 stance. 
 
 Water is almost a universal solvent; other liquids are 
 solvents to a certain extent. In chemistry, not only 
 solids dissolve in liquids, but liquids dissolve heavier or 
 lighter liquids or gases. 
 
 A Simple Solution is the action between a solid 
 and a liquid when brought into contact, by which the 
 solid without change of its actual properties becomes 
 also a liquid, and is uniformly diffused through the 
 former liquid. 
 
 A Chemical Solution is the action of a liquid 
 upon a solid, reducing the solid to a liquid by changing 
 the actual chemical characters of both the original solid 
 and the liquid. 
 
 Fusion is the conversion in an unchanged state into 
 liquids by heat, (melting.) 
 
 In strict accordance with the laws of chemistry, if 
 two substances be brought together under proper cir- 
 cumstances, the elements of which each is composed 
 may act upon each other, or react; and changing their 
 character produce other substances. This is a reac- 
 tion. 
 
 A Reagent is the chemical substance which is 
 brought into contact with another to cause it to change 
 its character. 
 
 When one substance reacts upon another the product 
 may be either solids, liquids or gases ; or solids and liq- 
 uids and gases without regard to the physical character 
 of the reagents. 
 
 Eeactions take place readily between liquids and solu- 
 tions of solids ; almost instantaneously between gases ; 
 but very slowly, if at all, between solids, because free- 
 dom of movement of the molecules, to bring them 
 quickly in contact with each other, is essential to speedy 
 chemical action. 
 
 Bertholet's Law. If, when two substances in liq- 
 uid form are brought together, a reaction takes place, 
 forming a substance, solid and insoluble in the liquid 
 
present, that substance will form and separate as a pre- 
 cipitate. 
 
 If a gaseous body can form, it will form and escape 
 as a gas or vapor. 
 
 When a precipitate has settled in a vessel in which a 
 reaction has taken place, it may be separated from the 
 liquid, by decantation ox filtration of the liquid. 
 
 Decantation is simply the pouring off of the super- 
 natant liquid. It is sometimes employed alone, and 
 sometimes before filtration. 
 
 Filtration is the process of straining, and thus sep- 
 arating the liquid from the solid. The filter is that 
 through which the liquid is strained. It may be coarse, 
 porous paper, muslin, asbestos, or glass wool — paper 
 filters are most commonly used. 
 
 After the liquid or filtrate has passed through the filter, 
 if the solid or precipitate is desired, it may be washed by 
 gently adding water until the water escapes clear. 
 
 The precipitate may be removed from the filter by 
 inverting the funnel containing it over an evaporating 
 dish, and washing the filtrate with a fine stream of water 
 into the dish; or a part of it may be removed by a glass 
 rod; or the filter may be taken out of the funnel and 
 spread over a drier and dried, and the precipitate re- 
 moved when dried; or a hole may be punched through 
 the bottom of the filter in the funnel and the precipitate 
 washed through into a clean vessel. 
 
 Evaporation is the conversion of a liquid into a 
 vapor by heat ; the vapor escaping and thus exhausting 
 the liquid. 
 
 Distillation is the rapid evaporation of a liquid and 
 its immediate re-conversion by cold to the liquid form 
 (condensation). 
 
 Sublimation is the conversion of a solid directly into 
 a vapor by heat, and its immediate re-conversion into the 
 solid form by cold. Only a few solids will sublime. 
 
 Desiccation is the complete removal of water from 
 a solid substance, either by heat or by exposure to some 
 chemical substance which has a great affinity for water, 
 as strong sulphuric acid. 
 
 Incineration is the application of sufficient heat to 
 a quantity of matter to remove all the volatile and 
 
 53 
 
organic matter from the non-volatile and inorganic 
 matter. 
 
 GENERAL WORKING RULES. 
 
 1. Keep everything on your table or shelves in per- 
 fect order, always replacing everything immediately 
 after using it. 
 
 2. Keep the reagent bottles on the shelves in their 
 numerical order with the labels outward. 
 
 3. Always see that your reagent bottles are filled 
 before you begin to work. 
 
 4. In using liquid tests, hold the stopper of the bot- 
 tle in the left hand (do not lay it down), and with the 
 bottle in the right hand, 2?our out of the tack of the mouth 
 of the bottle the very least quantity necessary to produce 
 the reaction, pouring very slowly, or drop by drop. 
 
 5. Use a separate portion of the substance you are 
 testing at each test, unless directed otherwise. 
 
 6. Follow your directions closely, literally, and if the 
 results are not as expected, ask for an explanation. 
 
 7. Never use any piece of apparatus unless it is per- 
 fectly clean, and after working see that everything is 
 clean and in its place before you leave. 
 
 8. Write the results of the reactions obtained care- 
 fully in your notes, using the formula? as previously 
 instructed, being sure that the formula? are correctly 
 written. 
 
 9. In writing reactions, it is convenient to use the 
 following abbreviations : 
 
 Ppt. — Precipitate. Pt. or pts. — Part or parts. 
 
 Sol. — Soluble. Sp.gr. — Specific gravity. 
 
 Insol. — Insoluble. Gtt. — Drops. 
 
 Soln. — Solution. P. E. — Equal parts. 
 
 Dil. — Dilute. Con. — Concentrated. 
 
 PRELIMINARY WORK. 
 
 10. Dissolve some potassium nitrate in a little water 
 in a test tube. The result is a simple solution. 
 
 11. Put a small piece of marble (CaC0 3 ) into a 
 tube, add a little water and boil. No change. Add five 
 drops of hydrochloric acid. An effervescence occurs, a 
 gas escapes. Result is a chemical solution. The reac- 
 tion is (Ca // C0 3 )+2(HCl)=(Ca"Clo)+(H 2 0)+CO,. 
 
12. Dissolve some sulphate of copper in a little 
 water in a tube. The result a simple solution. Pour 
 the solution into the evaporating dish and slowly evap- 
 orate. Result : the recovery of the original salt. 
 
 13. Dissolve sodium carbonate in a test tube. Add 
 hydrochloric acid. Pour into the evaporating dish and 
 evaporate. Taste the salt recovered. Reaction Na 2 (C0 3 ) 
 +2 (HCl=2(NaCl)+H 2 0+(C0 2 ). 
 
 14. To a little water in a tube, add a little barium 
 chloride solution. To this add five drops of sulphuric 
 acid. A white precipitate quickly forms. Reaction : 
 (Ba"CL,)+(H 2 (S0 4 )=(Ba / '(S0 4 +2(HCl). 
 
 15. Decant the above liquid into another tube. Add 
 a small piece of marble; effervescence. Reaction the 
 same as number two. 
 
 16. To a little water in a tube, add a little barium 
 chloride solution, and to this add a little ammonium 
 carbonate solution. Reaction : Ba"Cl 2 +2(NHj) (C0 3 )= 
 (Ba"C0 3 )+2(NH 4 Cl). 
 
 17. To a little dilute nitrate of silver solution add a 
 little of the potassium iodide solution. Reaction : 
 Ag(N0 3 )+KI=AgI-f-K(N0 3 ). 
 
 Decant the supernatant liquid, and evaporate and 
 recover the potassium nitrate salt. 
 
 18. To the precipitate add a little strong sulphuric 
 acid. Result : Change of color and violet vapors of 
 iodine and hydriodic acid. 
 
 19. To a little dilute nitrate of silver solution, add a 
 few drops of hydrochloric acid, and study the appear- 
 ance of the precipitate. Reaction : Ag(N0 3 )+HCl= 
 AgCl+H(N0 3 ). 
 
 20. To a little dilute sodium phosphate solution add 
 a few drops of the nitrate of silver solution. Reaction: 
 Na B (P0 4 )+3(Ag(NO a )=(Ag,(P0 4 )+3(Na(N0 8 ). 
 
 21. Treat one-half the precipitate with aqua am- 
 monia. It dissolves. Treat the other half with nitric 
 acid. It dissolves. 
 
 22. Dissolve some sulphate of copper in a tube. 
 Add a few drops of sulphuric acid, and dip a pen-knife 
 blade or piece of bright metal into it. Result : Free 
 copper deposited on the blade. 
 
23. Cut glass tubing into lengths of about seven 
 inches; draw out into sublimation tubes. 
 
 24. Wash a piece of platinum foil, and ignite it in 
 the flame until it no longer colors the flame yellow. 
 
 25. Place a piece of marble on the foil, and heat it 
 in the flame to a bright redness. It neither burns, 
 blackens, nor disappears in a vapor — an inorganic, non- 
 volatile body. 
 
 26. Heat a piece of ammonium chloride on the foil. 
 It disappears; volatizes without change of color — an in- 
 organic volatile body. 
 
 27. Heat a shaving of horn on the foil. It burns 
 and blackens with the peculiar odor of burning hair. It 
 contains carbon and nitrogen — an organic nitrogenized 
 body. 
 
 28. Heat a piece of starch on the foil. It burns and 
 blackens without the odor of burning hair. It contains 
 carbon but no nitrogen — an organic non-nitrogenized 
 body. 
 
 TOXICOLOGY. 
 
 A poison is any substance which, after absorption into 
 the blood, is capable of producing deleterious effects. 
 
 A corrosive is a substance capable of producing 
 deleterious effects by its chemical action upon the tissues, 
 with which it comes in direct contact, without absorp- 
 tion into the blood. 
 
 Sources of evidence of poisoning are : Symp- 
 toms — Post-mortem apj?ea?nnces and chemical analysis. 
 
 In forming an opinion in a case of suspected poison- 
 ing the medical examiner must acquaint himself with the 
 special character of the symptoms, the previous health 
 and habits of the patient, when fo6d or drink was last 
 taken, whether any peculiar odor or taste was observed 
 in the food, and whether others partook of the same. 
 
 The investigation should be made in the presence of 
 the proper law officer and one or more other physicians. 
 All appearances should be carefully noted at the time 
 of their observance, the length of the time the patient 
 has been dead, how long he survived the first symptoms, 
 and the external condition of the body. 
 
In the dissection, the condition of the entire alimen- 
 tary canal and of all the organs essential to life should be 
 minutely examined. g , 
 
 The success or futility of the chemists' labors depend 
 upon the knowledge and care of the physician during the 
 post-mortem, which should, if possible, be conducted in 
 the presence of the chemist who is to perform the analysis 
 The stomach and intestines and their contents should 
 be removed with both ends ligated. And, in addition, 
 a portion of the liver, blood, one kidney, the spleen, 
 heart the brain and a piece of muscle and the urine 
 found in the bladder. The stomach and intestines 
 should be placed in one vessel, the other organs, etc., 
 in another, the brain in another, and the urine in a 
 bottle These vessels must be of glass, and new and 
 clean They must be sealed with glass stoppers or new 
 corks securely tied and heavily coated with paraffine, 
 to be opened only by the chemist who is to perform the 
 analysis. 
 
 STRYCHNINE. 
 
 29 Strychnine is the alkaloid of the strychnos 
 nux Vomica. It is a vegetable basic substance with an 
 intensely bitter taste in aqueous solution, tne ^ A b ^ n g 
 recognized in a solution containing one part in 600 000. 
 
 30. Tests. Make a solution of the sulphate of 
 
 s rye m » agte a drop of the dilute so i ut i on5 an d observe 
 
 its persistent and intensely bitter taste. ...... 
 
 32 Drop into the solution a minute crystal of the 
 potassium bichromate. Observe the coloring—first blue, 
 then violet, changing to rose pink, then to yellow. 
 
 33 Dip a crystal of strychnia into a solution ol 
 iodic acid in sulphuric acid. Observe the yellow color, 
 changing to brick red, then to violet. 
 
 34 Place a crystal of strychnia in a watch glass on 
 white paper, and near it a small crystal of potassium bi- 
 chromate, and drop on to each separately a drop of strong 
 sulphuric acid. After a moment, carefully mix the two 
 solutions. Observe the blue color, then violet, then red, 
 then the entire fading of all color. 
 
35. If the most minute quantity of a strychnia solution 
 be injected under the skin of a frog's back, it will quickly 
 produce violent convulsions of a tetanic character. This 
 is not absolutely reliable as other substances, and some- 
 times only warm water will produce the same effect. 
 
 36. One-sixth of a grain of strychnia is considered a 
 fatal dose. The author has given one-seventh of a grain 
 of the sulphate as an inter-muscular injection, in a severe 
 case of hemiplegia, without unpleasant results. Severe 
 tetanus has resulted from the use of one-tenth of a grain. 
 
 37. The symptoms of poisoning by strychnia arc 
 severe muscular contractions and lockjaw, following 
 quickly after taking the medicine. It produces a sense 
 of suffocation and thirst, and often vomiting, and con- 
 traction of the pupils during the spasm. Death usually 
 occurs within two hours. 
 
 38. Treatment. Place the patient under the influ- 
 ence of chloroform, if in convulsions, and quickly use 
 the stomach pump. Wash out the stomach for a few 
 times every five minutes with water containing pulver- 
 ized charcoal in suspension, or with strong tea. Give 
 full doses of chloral hydrate and the bromides. Gel- 
 seminum, hypodermically, is of value. Morphine and 
 camphor, and oxygen by inhalation, are active antidotes. 
 
 MORPHINE. 
 
 39. Morphine is one of the 18 alkaloids of opium, 
 odorless and very bitter. Soluble, one part in 1,000 of 
 cold water. 
 
 40. Tests. Drop on to some crystals of morphia in 
 a watch glass a few drops of strong nitric acid; an 
 orange red color, changing to yellow is produced. 
 
 41. Dissolve a small portion of the sulphate of 
 morphia in water, and add a few drops of a neutral solu- 
 tion of the chloride of iron ; a blue color is produced. 
 
 42. Add to a solution of morphia a few drops of a 
 solution of iodic acid, a yellow color is produced ; to this 
 add a few drops of chloroform and shake violently. The 
 chloroform will assume a deep violet color, and separate 
 at the bottom. 
 
43. Mix a few crystals of morphine with cane sugar, 
 and add a drop of strong sulphuric acid. A dark red 
 color is produced. 
 
 44. Chloride of gold, when mixed with a solution of 
 the salts of morphia, gives a yellow precipitate, which 
 turns violet blue. 
 
 45. Morphia is a well-known active poison — more 
 active with children than with adults. One grain, taken 
 within six hours, has produced the death of an adult. 
 The symptoms come on gradually, and death generally 
 occurs within twelve hours, though often prolonged. 
 The symptoms are profound stupor, contracted pupils, 
 cyanosis, slow pulse and respiration. 
 
 46. Treatment. If there is a probability that the 
 poison is not all absorbed, wash out the stomach with a 
 strong infusion of coffee or green tea. Give strong 
 coffee freely, and hypodermatic injections of atropine in 
 the earliest stages. Hot baths are of some service. 
 Keep the patient moving. 
 
 ATROPINE. 
 
 C„HnNO s . 
 
 47. Atropine is the alkaloid of the atropa bella- 
 donna. It is a vegetable alkaline substance ; bitter, 
 sparingly soluble, and volatilizes upon the boiling of its 
 solutions. 
 
 48. Tests. Dissolve a crystal of potassium bi-chro- 
 mate in strong sulphuric acid ; add a crystal of atropine 
 and a few drops of water ; observe the odor of orange 
 blossoms. These two solutions remaining in contact 
 for a few hours turn green. 
 
 49. The colorless solution of atropine in sulphuric 
 acid does not turn red by nitric acid, indicating the 
 absence of morphia. 
 
 50. . Add to a strong solution (50 per cent.) of mor- 
 phine a five per cent, solution of corrosive sublimate. 
 Observe the red precipitate. 
 
 51. A few drops of a dilute solution of the salts of 
 atropine dropped into one eye of a cat will quickly 
 produce dilation of the pupil. Compare the two eyes. 
 
 52. Atropine is an active and violent poison. A 
 
small fraction of a grain will produce death. It pro- 
 duces dryness of the throat, dilation of the pupil, loss of 
 speech, delirium, coma and death. 
 
 53. Treatment. Evacuate the stomach, administer 
 stimulants, give morphine hypodermically, and glycer- 
 ine to overcome the sensation of strangling, produced 
 by the extreme dryness of the throat. 
 
 HYDROCYANIC ACID. 
 
 {IICN) Hydrogen Cyanide. 
 
 54. Hydrocyanic or Prussic Acid is a powerful 
 organic acid. It is obtained from bitter almonds, peach 
 and cherry pits, and from laurel water, and is found in 
 the juice of the cassava. It can be formed by chemical 
 processes, synthetically. 
 
 55. Tests. — The characteristic odor of hydrocyanic 
 acid, that of peach bloom, will assist in its detection. 
 
 56. Drop into a solution of the acid a few drops of 
 a solution of nitrate of silver. Observe the dense white 
 precipitate which dissolves both in nitric acid and in a 
 solution of potassium cyanide. 
 
 57. To a solution of the acid add a solution of the 
 ammonium sulphide. Evaporate this to dryness in a 
 water bath, and add to the residue a solution of the fer- 
 ric chloride. Observe the deep red color. 
 
 58. To a solution of the acid add a few drops of a 
 solution of picric acid. Heat the mixture; then cool it. 
 Observe the deep red color. 
 
 59. Dip a piece of filter paper into an alcoholic solu- 
 tion of guaiacum, and then into a dilute solution of 
 sulphate of copper. The vapor of hydrocyanic acid 
 will turn this paper a deep blue. 
 
 60. Hydrocyanic acid is a violent poison when either 
 inhaled or taken internally. The anhydrous acid vapor 
 will produce almost instant death to small animals. If 
 enough is taken death occurs quickly. There is but 
 little time to administer antidotes. 
 
 61. Treatment. — The stomach pump should be 
 used, artificial respiration, electricity, inhalations of am- 
 monium, and cold affusion. If the patient does not die 
 within an hour he may be saved. After death the body 
 exhales a marked odor of the poison. 
 
62. When death is suspected from this poison, and 
 an analysis is to be made, do not open the stomach until 
 the analysis is to he begun. 
 
 OXALIC ACID. 
 
 63. Oxalic Acid is a crystalline, organic acid. It 
 occurs as oxalates in the juices of many plants and trees, 
 and as an excrete product in urine. It has an acid taste, 
 and reddens litmus. 
 
 64. Tests. — Neutralize a solution of the acid with 
 a little ammonium hydrate; then add a solution of cal- 
 cium chloride. Observe the white precipitate, which will 
 dissolve in hydrochloric acid. 
 
 65. Crystals heated with sulphuric acid decompose 
 into gases CO and CO,, etc., and do not char 
 
 66. To a solution of the acid add a few drops of 
 barium chloride solution. Observe the white precipitate, 
 soluble in hydrochloric; insoluble in acetic acid. 
 
 67. To a solution of the acid add a few drops of a 
 nitrate of silver solution. A white precipitate forms, 
 soluble in nitric acid and in aqua ammonia. 
 
 68. Oxalic acid is a violent poison. It acts as a cor- 
 rosive and as a true poison. In dilute solutions it may 
 produce death like a narcotic. In strong solutions it is 
 corrosive. Death occurs quickly, generally within half 
 an hour. 
 
 69. Treatment. — Do not use the stomach pump. 
 Neutralize with lime or magnesium (not the carbonates), 
 in suspension in a little water. If no vomiting and no 
 corrosion, after a time give emetics. 
 
 ARSENIC. 
 
 As. m - 75. 
 
 70. Tests. Heat some crystals of the arsenious 
 oxide in a sublimation tube. The substance disappears, 
 and minute diamond-like crystals of the sublimate form 
 on the walls of the tube above. 
 
 71. Heat a portion of the metallic arsenic in a tube. 
 The sublimate forms in zones— steel gray, black, and 
 dirty gray. 
 
 72. Break off the lower end of the last tube and 
 heat again. Observe the diamond-like crystals of the 
 
sublimate of arsenious oxide, formed by the action of 
 oxygen on the elementary arsenic. 
 
 73. Drop some crystals of the oxide into a tube and 
 on top of the crystals some minute charcoal chips. Heat 
 the charcoal to redness, then heat the oxide. Observe 
 the gray and black zones of elementary arsenic. The 
 oxygen of the oxide has combined with the carbon of 
 the charcoal, and set the arsenic free. 
 
 74. Break off the point of this tube and heat the 
 zones, and observe the white crystals of the sublimate 
 of the oxide re-form on the tube above. 
 
 75. Heat a small portion of paris green in a subli- 
 mation tube. Observe the white diamond-like crystals 
 of arsenious oxide form above. 
 
 76. Place some paris green in another tube, and add 
 chips of charcoal. Heat the charcoal, then the green. 
 Observe the black zones of elementary arsenic. Break 
 off the tip of the tube, and heat again, and observe the 
 white crystals. 
 
 77. Prepare a solution of arsenious oxide (As 2 8 ) 
 by boiling. 
 
 78. Take a little of the solution in the test tube, 
 dilute it with equal parts of water. Add 20 drops of 
 hydrochloric acid ; no result. It is necessary to acidu- 
 late many solutions with hydrochloric acid before add- 
 ing the hydrogen sulphide, or the sulphide of the metal 
 will not precipitate. 
 
 79. Add a solution of hydrogen sulphide freely to 
 the mixture. Observe the yellow precipitate of the 
 sulphide of arsenic. 
 
 80. Warm this and allow the precipitate to separate 
 and settle ; decant ; if necessary, filter. 
 
 81. Place a little of the precipitate in each of two 
 watch glasses. Add to one ammonium hydrate. It 
 dissolves. Add to the other hydrochloric acid. It does 
 not dissolve. 
 
 82. Dry a portion of the precipitate, then mix it 
 with twice as much potassium cyanide. Place it in a 
 sublimation tube and heat. Observe the gray and black 
 zones of the elementary arsenic. Break off the point 
 of the tubes and heat the zones. Observe the white 
 crystals of the arsenious oxide. 
 
83. Fill a small test tube half full of water; add 
 two drops of ammonium hydrate. Then add drop by 
 drop a solution of sulphate of copper until the precipi- 
 tate no longer dissolves. To this add a little of the 
 arsenic solution. Observe the green precipitate. Agitate, 
 and allow to settle ; decant. Pour half of the precipi- 
 tate into another tube ; add to one tube nitric acid 
 (HN0 3 ) ; the precipitate dissolves in a colorless solution. 
 Add to the other tube ammonium hydrate ; the precipi- 
 tate dissolves in a deep blue solution. 
 
 84. Prepare a solution of ammonium hydrate, as 
 above, and add drop by drop a solution of nitrate of 
 silver, instead of the sulphate of copper, in the same 
 manner. To this, add the arsenic solution. Observe 
 the canary yellow precipitate. Decant, and divide the 
 precipitate into two portions. Treat one with nitric 
 acid, and the other with ammonium hydrate. Observe 
 the perfect colorless solution with both. 
 
 85. Reinsch's Test. Boil narrow strips of bright 
 copper foil in an arsenic solution, acidulated with hydro- 
 chloric acid. The copper becomes gray, then black, 
 from the deposit of arsenious oxide. If arsenic is in 
 excess, it forms in scales. 
 
 86. Remove the copper, dry it carefully with filter 
 paper, place in a dry test tube and heat. Observe the 
 white diamond-like crystals of the sublimate of the 
 arsenious oxide. 
 
 87. Arsenic has long been the most commonly used 
 of all poisons for homicidal and suicidal purposes. Inas- 
 much as it is easily detected, and produces a most pain- 
 ful death, this fact is a peculiar one. If taken in large 
 doses, its emetic effect sometimes produces immediate 
 evacuation of the stomach, in man, and no permanently 
 serious results accrue. 
 
 88. Taken in small doses, persisted in and continued, 
 the system can become habituated to it until a very large 
 quantity may be taken without bad effect. 
 
 89. The poisonous effects are those of an irritant to 
 the intestinal tract and nervous system. From two 
 grains of the oxide upward will produce death, which 
 occurs within 24 hours. 
 
90. Treatment. If the case is seen immediately, 
 the stomach pump may be used. If not, emesis may be 
 produced by the sulphate of zinc in large quantities of 
 warm water, or by the hypodermic injection of apomor- 
 phia, T \ to -J of a grain. The chemical antidote must 
 then be immediately administered. Dialized iron is 
 very efficacious, given in doses of five grains for every 
 grain of the arsenic salt. Or the hydrate of iron, in 
 moist magma, quickly prepared by mixing the liquor 
 ferri persulphate, or the tincture of the ferrous chloride, 
 with one-third their bulk of aqua ammonia, and collect- 
 ing the moist product on a muslin cloth ; wash it until 
 all smell of ammonia is gone. Give teaspoonful doses 
 every five minutes until at least 20 times as much as the 
 arsenic salt is taken. 
 
 ANTIMONY. 
 
 Sb. m. 
 
 91. As a poison, it acts upon man and carnivorous 
 animals, but upon cattle and horses it has but little effect. 
 In enormous doses persisted in, it produces emaciation 
 and ultimately slow death. The tartar emetic is very 
 violent in its effect on man. 
 
 92. Tests. Prepare a solution of the tartar emetic 
 (K(SbO)C 4 H 4 6 ) in water by heat, if necessary. 
 
 93. Fill a tube one-fourth full of the solution. Add 
 two drops of hydrochloric acid. A white precipitate 
 forms (Sb 2 O s ) soluble in excess of the acid. 
 
 94. Add a solution of hydrogen sulphide freely to 
 this mixture. Observe the heavy orange red precipitate 
 of the ammonium sulphide, and distinguish between 
 this and the sulphide of arsenic. 
 
 95. Decant and separate the precipitate into two 
 parts. Add to one part ammonium hydrate. It does 
 not dissolve. 
 
 Add hydrochloric acid to the other portion. It dis- 
 solves if slightly warmed. 
 
 96. Reinsch's Test. Boil narrow strips of copper 
 foil in the solution acidulated. Observe the bluish 
 gray, purple, or violet deposit. Heated in a sublimation 
 tube, the sublimate is amorphous, not crystalline, and 
 deposits close to the slips. 
 
97. Antimony is an irritant in its poisonous effects. 
 Two grains has produced death in an adult man. Ten 
 grains is the poisonous dose. Death occurs in from 
 four to six hours. 
 
 98. Treatment. The stomach must be evacuated, 
 large quantities of warm water being used. Strong 
 decoctions of vegetable astringents, as oak bark, tannin, 
 nutgalls or green tea, are then given. 
 
 LEAD. 
 
 PI. 207. 
 
 99. Poisoning by lead is apt to occur accidentally 
 from the varied uses of the substance. 
 
 The oxides, nitrates or carbonates are most likely to 
 be the salts used. 
 
 100. Tests. Prepare a solution of the acetate or 
 nitrate of lead in water. 
 
 101. Fill a test tube one-fourth full of the solution ; 
 add two drops of hydrochloric acid. Observe the white 
 precipitate (PbCL) soluble in excess of water. 
 
 102. Add a solution of the hydrogen sulphide freely 
 to this mixture. Observe the brownish black precipi- 
 tate ; distinctively colored at first (PbS). 
 
 103. Collect the precipitate and divide it into two 
 parts. Add to one part strong nitric acid, warm. The 
 black sulphide is changed to the white sulphate (PbS0 4 ). 
 
 104. Add to the other part dilute nitric acid, and 
 boil. The precipitate dissolves. 
 
 105. To a portion of the original solution add a few 
 drops of the potassium iodide solution. Observe the 
 deep yellow precipitate (PbL) solution. 
 
 106. To a portion of the solution add a small quan- 
 tity of the potassium bi-chromate solution. Observe the 
 yellow precipitate. Add potassium hydrate solution; 
 the precipitate dissolves. 
 
 107. Lead poisoning is most commonly of a chronic 
 character. It is induced in man and animals by taking 
 the lead in slowly with food or drink. Man is poisoned 
 by the frequent handling of lead substances, and animals 
 have been slowly poisoned by eating grass near smelting 
 works where the soot from the w r orks was deposited on 
 the grass. It acts upon the nervous system. Death 
 does not often occur quickly. 
 
 65 
 
108. Treatment. In acute poisoning the sulphates 
 of soda or magnesium may be given freely after evacua- 
 tion of the stomach. In chronic poisoning the iodide of 
 potassium is of value; and the water drank may be per- 
 sistently acidulated with sulphuric acid. 
 
 MERCURY. 
 
 Eg. WO. 
 
 109. In these tests we use the two chlorides of mer- 
 cury. There are some differences in their reactions. 
 
 THE OUS REACTIONS. THE IC REACTIONS. 
 
 110. Heat a little cal- Heat a little corrosive 
 omel in a sublimation tube. sublimate in a tube. It 
 
 It turns yellow; does not 
 fuse; it sublimes. 
 
 111. Suspend a little 
 calomel in water; it does 
 not dissolve. 
 
 112. To a little of the 
 above mixture add a few 
 drops of hydrochloric acid. 
 No result. 
 
 113. To the acidulated 
 mixture add a solution of 
 hydrogen sulphide in ex- 
 cess. Observe the black 
 precipitate immediately 
 formed and colored. 
 
 114. To a little of the 
 mixture add a little aqua 
 calcis. Observe the black 
 precipitate. 
 
 115. Add to the mixture 
 a little potassium hydrate 
 solution. Observe the 
 black precipitate (Hg.,0). 
 
 116. 
 
 turns yellow, fuses, and 
 sublimes. 
 
 Prepare a solution of the 
 corrosive sublimate. 
 
 Fill a test tube one fourth 
 full of the sublimate solu- 
 tion. Add a few drops of 
 hydrochloric acid. No re- 
 sult. 
 
 Fill the tube with the 
 solution of hydrogen sul- 
 phide. Observe the white, 
 light yellow, dark yellow, 
 light brown, dark brown, 
 to black shading, gradually 
 formed, and gradually deep- 
 ening to the black. 
 
 To a little of the solution 
 add a little aqua calcis. 
 Observe the yellow pre- 
 cipitate. 
 
 Add to the solution po- 
 tassium hydrate. Observe 
 the red precipitate (HgO). 
 
 Add to the solution a 
 little of the potassium io- 
 dide solution. Observe the 
 yellow to red precipitate. 
 
117. Treat the sulphide of either of the chlorides 
 with nitric acid. They are partially soluble. They are 
 soluble in equal parts of nitric and hydrochloric acids. 
 
 118. Reinsch's Test, performed as with arsenic 
 and antimony, produces a silver-gray coating on the 
 copper. 
 
 Dry and heat in a sublimation tube; the mercury sub- 
 limes on the sides, and at the bottom of the tube in 
 minute coalcscent globules of free mercury — quicksilver. 
 
 119. Dip a piece of copper or gold in a solution of 
 the corrosive sublimate, and rub the surface through the 
 solution with the point of a knife blade. The mercury 
 is deposited on the metallic surface. 
 
 120. The salts of mercury are active poisons, and 
 recently many deaths have resulted from using the cor- 
 rosive sublimate as an antiseptic. Taken in sufficient 
 quantity, it produces effects similar to arsenic poisoning, 
 except that the effects begin and terminate more quickly. 
 
 121. Treatment. Administer the white of an egg, 
 and after a few minutes evacuate the stomach ; then 
 administer another egg and again evacuate the stomach. 
 In cases of slow, or chronic poisoning, the iodides of 
 sodium or potassium should be given for a long time. 
 
 PHOSPHORUS. 
 
 P. 31. 
 
 122. Tests. It may be known by its peculiar gar- 
 licky odor, and by its luminosity in the dark. 
 
 123. Boil a little starch in some water in a test tube; 
 to this add as much potassium iodide as the starch. 
 Saturate a piece of filter paper with this double solu- 
 tion. This paper, exposed moist to the vapor of phos- 
 phorus, is turned blue. 
 
 124. Phosphorus acts as an acute, and as a chronic 
 poison. It is also a poisonous escharotic. Children are 
 poisoned from match heads. It kills by depriving the 
 blood of its oxygen, and death occurs quickly where suffi- 
 cient has been taken. 
 
 125. Treatment. There is no known chemical 
 antidote. Evacuate the stomach, and administer an old 
 oil of turpentine. Avoid all fixed oils or fats. The 
 calcium and magnesium carbonates in solutions or sus- 
 pensions are thought to be of advantage. 
 
WATER. 
 IL,0. 
 
 Water, because of possible impurities in suspension 
 or in solution, may be the cause of disease and death. 
 
 The clearness of water is not an indication of its 
 purity. Rain water may be found to contain on evapo- 
 ration 40 parts of residue. 
 
 The water of shallow wells is apt to contain much 
 impure organic matter in solution. The application 
 of a few simple tests will determine the presence of 
 impurities. 
 
 Tests. Fill a large bottle half full of water ; shake 
 thoroughly, and smell. If there is any odor, there is 
 an excess of impurities. 
 
 Evaporate 8 or 10 ounces of water, and observe if 
 any odor is present. The amount of odor is in propor- 
 tion to the quantity of organic impurities, and, if present, 
 there will be a black residue on complete evaporation. 
 
 Weigh the dish and residue; then heat until the black 
 residue is converted into a white ash ; weigh again, and 
 the difference in the two weights will be the amount of 
 organic matter in the quantity of water used. 
 
 Take a definite quantity of water and strongly acidu- 
 late with concentrated sulphuric acid. Add to this, 
 from a burette over white paper, a known solution of 
 potassium permanganate. When the salt solution ceases 
 to be decolorized in the water, read on the burette the 
 amount used, and estimate the amount of nitrogenized 
 organic matter present. 
 
 Nitrites in water are a strong evidence of decom- 
 posed animal matter. 
 
 Tests. Concentrate a quantity of water to one-third 
 its bulk. Acidulate with dilute sulphuric acid; add a 
 few drops of a potassium iodide solution, and a small 
 quantity of a solution of starch. The nitrites present, 
 if any, will permit the immediate formation of the blue 
 iodide of starch. 
 
 Nitrates will not produce this reaction. 
 
 The inorganic impurities in water are the chlor- 
 ides, sulphates or carbonates of magnesium, calcium, 
 sodium, or potassium. These salts cause the hardness 
 of water. 
 
If the hardness may be removed by boiling, it is tem- 
 porary. If not so removed it is permanent. 
 
 Tests. Cleanse a platinum foil by burning until it 
 ceases to color the flame yellow. 
 
 Burn on the foil a portion of the inorganic residue of 
 evaporated water. A momentary violet tint appears; 
 potassium is present. If yellow, the salt is sodium; if 
 orange-red, it is calcium. 
 
 Add to the water a solution of nitrate of silver; if an 
 opaque or white cloud appears, chlorine is present, prob- 
 ably in combination with the element detected in the 
 above test. 
 
 Water may be purified by distillation, by boiling, or 
 by filtration. Distilled water is not fit for continued 
 use, as it is not properly aerated. 
 
 ANALYSIS OF URINE. 
 
 Chapter V. 
 
 Urine is a solution in water of the products of the 
 retrograde metamorphosis of the body, secreted by the 
 kidneys. 
 
 Quantity. An adult male in health passes about 
 1,000 grains of solids in twenty-four hours, in solution 
 in from forty-six to fifty-six ounces of water. 
 
 The normal constituents, and their approximate pro- 
 portions, are exhibited in the accompanying table: 
 
 CONSTITUENTS. 
 
 Parts 
 
 Per Thousand 
 
 of Urine. 
 
 Approximate 
 Quantity in 24 
 Hours in Grains. 
 
 Per Cent. 
 
 -of 
 
 Total Solids. 
 
 Water 
 
 Urea 
 
 Uric Acid 
 
 Hippuric Acid 
 
 Chlorides '. 
 
 Phosphates 
 
 Sulphates 
 
 Kreatinin 
 
 Mucus and Coloring Matter 
 
 Urates . 
 
 Hippurates , 
 
 950.00 
 
 26.20 
 
 1.00 
 
 1.50 
 
 5.00 
 
 2.75 
 
 1.30 
 
 .87 
 
 .39 
 
 1.60 
 
 .75 
 
 550. 
 
 20. 
 
 30. 
 100. 
 
 50. 
 
 25. 
 
 18. 
 8. 
 
 32. 
 
 15. 
 
 55.0 
 2.0 
 3.0 
 
 10.0 
 5.0 
 2.5 
 1.8 
 .8 
 3.2 
 1.5 
 
Color. The color of urine varies from a wine-yellow 
 to amber. After the ingestion of large quantities of 
 fluids, it is almost colorless. After free perspira- 
 tion, when but little water has been taken, it is much 
 darker. 
 
 Colorless urine occurs in diabetes, and lactescent urine 
 in interstitial nephritis. Dark yellow or light brown 
 urine occurs in the initial stages of fevers and during 
 their course. 
 
 Dark red urine depends upon the presence of foreign 
 substances taken into the system ; and if dark brown or 
 black, blood is probably present. 
 
 Green urine is produced by jaundice (biliverdin), and 
 sometimes by indican (animal indigo), which also pro- 
 duces blue urine. In either case, especially if indican is 
 the cause of the discoloration, the urine is alkaline. 
 
 Normal urine should be clear, with a faint white cloud 
 of mucus suspended in the center. 
 
 If turbid, heat a small quantity in a test tube. If the 
 urine becomes clear, the cloudiness is caused by urates. 
 If the cloudiness remains or increases, but will disappear 
 on the addition of acetic acid, it is caused by the carbon- 
 ates or phosphates. If the cloud remains after the addi- 
 tion of acetic acid, then pus, blood or albumen are 
 probably the cause of the cloud. 
 
 Odor. The odor of human urine is faintly aromatic 
 in health, when first passed. If there is alkaline decom- 
 position, it is ammoniacal. If inflammation of the 
 bladder is present, it is fetid. 
 
 Food, drinks and medicines often impart odor to the 
 urine. 
 
 Reaction. Normal urine is slightly acid when 
 passed, because of the excess of organic acids and the 
 acid phosphates. Alkaline urine will follow the use of 
 the carbonates, acetates or tartrates. If there is disease of 
 the bladder, the urine may be alkaline from the decom- 
 position of the urea in the urine. Observe whether the 
 decomposition oocurred before or occurs after the pas- 
 sage of the urine. Strongly acid urine favors the for- 
 mation of calculi, and causes irritation of the kidneys 
 and bladder, and may induce structural change in those 
 organs. 
 
 70 
 
Specific Gravity. The specific gravity of human 
 urine, determined by the urinometer, varies between 
 1015 and 1021 when the normal quantity of urine is 
 passed. If the quantity passed varies, the specific grav- 
 ity varies in inverse ratio. 
 
 In disease, the specific gravity varies from 1003 to 
 1010. Low specific gravity is found in diabetes insipidus, 
 and in some forms of Bright's disease. High specific 
 gravity is found in diabetes mellitus, in lithsemia, and in 
 those cases where the water is scanty. 
 
 To determine approximately the total quantity of sol- 
 ids passed in 21 hours, multiply the last two figures of 
 the specific gravity by the arbitrary number, 1.125, as 
 a co-efficient. The product will be the number of grains 
 of solids in one ounce of urine. Multiply this by the 
 number of ounces passed in 21 hours, and that result 
 will be the desired amount. Estimate the percentage of 
 the total amount thus obtained, for the amount of any 
 single substance desired, from the percentage column 
 on page 69. This can only be approximately correct, 
 but is often of great assistance. 
 
 Phosphates. Take a five inch test tube three-fourths 
 full of urine, and boil: a white cloudiness appears. Fill 
 the tube to within one inch of full with the solution of 
 potassium hydrate. The cloud deepens. Set to one 
 side for twenty minutes ; the sediment settles to the bot- 
 tom. If the sediment is half an inch deep, the quantity 
 of the phosphates is about right ; if less than half an 
 inch, there is too little ; if an inch, there is too much. 
 
 The normal quantity of the phosphates is increased 
 after the taking of phosphorus in any form ; after the 
 eating of animal food in large quantities ; in many acute 
 febrile diseases, and the earthy phosphates are increased 
 after disease of the bones, or after nervous excitement 
 or exhaustion. They are decreased in all urine of low 
 specific gravity, in diseases of the kidneys and heart, in 
 brain disorders, and in certain forms of dyspepsia. 
 When present in great excess, they will be precipitated 
 and form a sediment, especially when the urine is 
 alkaline. 
 
 Chlorides. Take a test tube half full of urine. Add 
 three drops of nitric acid to prevent the phosphate from 
 
being precipitated; then add, drop by drop, a few drops 
 of the solution of nitrate of silver. If white, cheesy 
 globules fall to the bottom, without much cloudiness, 
 there are enough of the chlorides. If there is a milky 
 cloudiness, with but little curdiness, there is too little of 
 the chlorides; if there is only a milky opacity, there is 
 a great deficiency of the chlorides. There is no change 
 in the appearance of the urine if the chlorides are 
 absent. 
 
 The chloride of sodium is an important constituent of 
 the animal body, and its excretion should be quite uni- 
 form. It is greatly in excess of the potassium chloride 
 in human urine. The chlorides are found diminished in 
 acute febrile diseases, and their increased diminution 
 foretells an increase of the disease, and an increase in 
 their quantity indicates improvement. Their absence in- 
 dicates a serious condition. They are also diminished 
 when there is effusion and dropsy. 
 
 Their sudden reduction in acute rheumatism foretells 
 a metastasis to the heart. 
 
 They are increased when much salt is taken ; after 
 physical and mental labor ; in diabetes insipidus ; and 
 when effusion is relieved by diuresis. 
 
 Sulphates. To a specimen of the urine add five 
 drops of hydrochloric acid; then add one-third as much 
 of the barium chloride solution as there is urine. If 
 there is a milky appearance, with afterward an earthy 
 precipitate, there is probably the normal quantity of 
 sulphates present. The sulphates of sodium and potas- 
 sium are the salts found. 
 
 They are decreased when meat diet is excluded, and 
 in the beginning of low fevers. They are increased with 
 meat diet; after taking any compounds of sulphur ; and 
 in acute fevers, when the urine has a high specific gravity, 
 especially in inflammatory diseases of the nervous or 
 muscular systems. 
 
 Urea. To a small quantity of the urine add one- 
 third as much strong nitric acid ; cool it immediately to 
 about fifty degrees, and shake it thoroughly; then let it 
 stand for five minutes. If the full normal quantity of 
 urea is present, a very few crystals of nitrate of urea 
 may be seen floating in the urine or attached to the sides 
 
 72 
 
of the tube. If more are seen an excess is present. If 
 albumen is present, it must be first precipitated and the 
 urine filtered. 
 
 To obtain the urea free, concentrate the urine to about 
 one-sixth its bulk ; then add an equal quantity of cold 
 nitric acid. Treat the crystals with the barium carbon- 
 ate solution; dry this product, and extract the urea with 
 alcohol. 
 
 Urea constitutes about one-half of the entire solids of 
 the urine. It represents the constant tissue change in 
 the body, and is the method of elimination of a portion 
 of the superfluous nitrogenous food. 
 
 Urea is increased when the diet is largely animal food ; 
 after violent muscular action; in the developing stages of 
 acute fevers ; in various nervous disorders ; and in some 
 cases of diabetes mellitus. It is diminished in structu- 
 ral disease of the kidneys ; in many forms of chronic 
 disease ; when the diet is exclusively vegetable, and in 
 starvation. Its retention in the system produces uraemia. 
 It is usually present in excess if the specific gravity is 
 high and sugar is absent. 
 
 Uric Acid. To a specimen of urine, add three per 
 cent, of its bulk of strong hydrochloric acid, and allow 
 the specimen to stand twenty-four hours. The minute 
 red crystals of uric acid will be deposited on the bottom 
 and sides of the vessel ; darker, or lighter, as the urine 
 is dark or light. 
 
 Murexid Test. Moisten some crystals of uric acid 
 with nitric acid. Evaporate the product nearly to dry- 
 ness ; the residue is a yellowish mass, if there is only a 
 small quantity of uric acid; pink or red, if the quantity 
 is large. To this, add a few drops of ammonium hy- 
 drate. An immediate rich purplish-red color appears 
 for a moment, then fades away. 
 
 Uric acid is constantly present in the urine of man, in 
 combination with sodium, potassium, and ammonium. 
 It varies with the kind of food taken, and in conditions 
 of disease. It cannot be found in the urine of infants 
 at the breast. It is the commonest ingredient of calculi. 
 It is in excess in all fevers, except yellow fever. It is 
 doubled in typhus, and in small pox. It is absent often 
 when urea is present in large quantities. 
 
 73 
 
Hippuric Acid. Evaporate from 16 to 20 ounces 
 of urine to one ounce, with constant stirring. Cool 
 and filter. To the syrupy filtrate, add 15 drops of con- 
 centrated hydrochloric acid. Stir well for a short time, 
 then treat it with a few ounces of pure ether, contain- 
 ing ten per cent, of absolute alcohol. Slowly evaporate 
 the etherial solution, and the hippuric acid will crystal- 
 ize in the vessel. Uric acid may be precipitated from 
 the urine before beginning the separation of the hip- 
 puric acid. 
 
 Hippuric acid is present in larger quantities in human 
 urine than uric acid, but is so easily soluble that it is 
 difficult of separation. It occurs in the largest quantity 
 after an exclusively vegetable diet. Cranberries, black- 
 berries, and plums increase it. Benzoic acid and balsam 
 of Peru, taken as medicines, produce an immediate in- 
 crease in the quantity of hippuric acid. It is increased 
 in diabetes, in typhus, in chorea, and in most inflamma- 
 tory disorders. 
 
 Albumen. Take a specimen of urine in a test tube, 
 and boil. A cloudiness forms, like that described as 
 phosphates. Add five drops of nitric acid ; the cloud 
 does not clear up as with the phosphates, but deepens, 
 and finally settles. This is albumen. 
 
 In alkaline urine, the nitric acid reacts upon the car- 
 bonates, and produces so much carbonic acid gas as to 
 interfere with the test. In these cases, treat the speci- 
 men with a few drops of acetic acid, and then boil ; a 
 cloud is produced, if albumen is present, which is not 
 dissolved by the addition of more acid. If very little 
 albumen is present, the above test may not be decisive. 
 Pour an inch of strong nitric acid into a clean tube, in- 
 cline the tube a little, and carefully allow a few drops of 
 the urine to run down the incline and gently diffuse it- 
 self on the top of the acid. A brownish-red color is 
 then observed at the line of union. Just above this is 
 a narrow white cloud, if the least albumen is present, 
 the intensity of the cloud depending on the quantity of 
 albumen. If much urea or urates are present, the crys- 
 tals may form higher up, but will disappear if warmed, 
 while the albuminous cloud will not. Do not boil, as 
 all albumen will dissolve in boiling: nitric acid. There 
 
is generally but little urea or urates found where albu- 
 men is present, and, for that reason, the specific gravity 
 is low, unless sugar is present. 
 
 The quantity of albumen passed may vary from the 
 least perceptible quantity, to enough to solidify the en- 
 tire quantity of urine passed when precipitated. 
 
 In the tubules of the kidneys, the normal condition 
 is one of diffusion. The animal membrane through 
 which the diffusion takes place permits the crystalline 
 substances (urea, and the normal salts of the urine) to 
 pass through with the water of the urine, from the blood, 
 but retains the non-cry stalliz able substances (colloids) 
 within the blood. If the pressure upon the membrane 
 is increased, or the membrane in any place destroyed, 
 the albumen may escape with the urine. Albumen is 
 not present, then, in normal urine. It is present when- 
 ever there is increased blood pressure in the vessels of 
 the kidneys (passive hyperemia), in structural diseases 
 of the kidneys (nephritis, Bright's disease), when pus 
 and blood are passed with the urine, and after the tak- . 
 ing of large quantities of egg albumen. 
 
 Sugar. Before testing for sugar, be sure that no 
 albumen is present. If it is, precipitate it by the tests 
 described, and filter the urine carefully. 
 
 Moore's Test. To a specimen of urine, add one-third 
 as much potassium hydrate, and boil. If sugar is pres- 
 ent, the mixture will turn yellow, then brownish yellow, 
 then brown, then nearly black, depending on the quan- 
 tity of sugar present. 
 
 Trommels Test. To a specimen of urine in a test 
 tube, add from 20 to 30 drops potassium hydrate solu- 
 tion ; then add, drop by drop, a solution of copper sul- 
 phate, shaking the mixture after each addition, until the 
 white cloud no longer dissolves. Boil the top of the 
 mixture ; the blue color changes to yellow, then to red, 
 if sugar is present. 
 
 If no sugar is present, a turbid dirty green or grayish 
 green mixture is produced. 
 
 Fehling's Test (Modified). Mix in a mortar a 
 drachm of pure sulphate of copper, five drachms of 
 rochelle salts, and two drachms of pure caustic soda 
 (sodium hydrate). 
 
Take a little of the paste, as large as a small pea, and 
 dissolve by boiling in a drachm or two of water in the 
 test tube. Add a few drops of the urine, and boil again. 
 If sugar is present, the blue color immediately disap- 
 pears, and red, or reddish brown, sub-oxide of copper is 
 precipitated. If no sugar is present, the blue color 
 becomes turbid ; may change to greenish blue, then to a 
 grayish green color, easily distinguished from the dis- 
 tinct light or dark reddish brown of the sugar specimen. 
 
 With Trommer's and Fehling's tests, an excess of 
 uric or hippuric acid, or the urates, will cause a redac- 
 tion of the copper oxide much like the sugar. They are 
 not always reliable for this reason. 
 
 Boettgeis Test. To a small quantity of urine in a 
 test tube, add an equal quantity of sodium carbonate 
 solution (1 to 3). To this add a small quantity subni- 
 trate of bismuth, and boil for some time. The powder 
 turns gray, then brown, then black, according to the 
 quantity of sugar present. It is unchanged if sugar is 
 absent. This test is very reliable. 
 
 Fermentation Test. Determine the exact specific 
 gravity of two specimens of the same urine. To one 
 of the specimens add a little yeast and set them both in 
 a warm place for 2-i hours, when the specific gravity is 
 again taken. The yeast specimen will be found lighter 
 than the other. Every degree of specific gravity it has 
 lost represents one grain of sugar in each ounce of the 
 urine. 
 
 Fit a large test tube or a bottle with a cork through 
 which passes a bent glass tube. Put into the vessel a 
 small piece of yeast, fill it full of urine and cork it tightly 
 with the tube passing nearly to the bottom. Set it in a 
 warm place and dip the open end of the tube into an 
 empty bottle. As fermentation progresses, every vol- 
 ume of gas generated will replace an equal volume of 
 urine, which will escape into the empty bottle, and can 
 be measured. Every grain of sugar decomposed will 
 form 17 cubic centimeters of gas, and replace four 
 fluid drachms and 36 minims of the urine. 
 
 Sugar is present in normal urine in too small a quantity 
 to be detected by the usual tests. Any quantity so dis- 
 covered is abnormal. It is found in large quantities only 
 
in diabetes mellitis. It appears temporarily in smaller 
 quantities after injuries to the brain or central nervous 
 structure, or after profound impressions upon the nervous 
 system ; in pregnancy, in uterine disease, and in certain 
 disorders of the digestion. It is thought to occur fre- 
 quently during the course of many severe inflammatory 
 disorders and prostrating fevers, and after taking cer- 
 tain medicines. 
 
 Its presence is important only when it is more or less 
 recurrent or permanent. 
 
 Blood. When blood is found in urine in any quan- 
 tity, serum albumen must be present also. If albumen 
 is present without blood, the product, coagulated by the 
 tests already described, are white. In the application 
 of the same tests, if any red blood cells are present, the 
 precipitated mass will be discolored from a light brown- 
 ish mass to a dark brown or nearly black precipitate, 
 according to the quantity of blood present, and the 
 urine above the precipitate will become quite clear. 
 When the phosphates are precipitated by the method 
 described, they will be red or reddish brown, instead of 
 their normal color, if blood is present. 
 
 Blood cells may be seen by examining a specimen 
 under the microscope. 
 
 Add a few drops of tincture of guaiacum to a little 
 urine in a test tube. To this add a mixture of ether and 
 per oxide of hydrogen (ozonic ether), and agitate. If 
 blood is present the ether will acquire a blue tint. 
 
 *Blood, blood cells, or blood coloring matter may be 
 found in the urine from a number of causes. From 
 hemorrhage from the capillaries of the parenchyma, as 
 a result of intense congestion, or greatly increased blood 
 pressure; from severe internal hemorrhages; from traum- 
 atism of the kidneys or bladder ; after severe muscular 
 exertions or violent strain ; in destructive structural dis- 
 ease of the kidneys or bladder, as in acute inflamma- 
 tion, and in cancer; often in Bright's disease. And blood 
 will be found sometimes persistently in the gouty or 
 uric acid diathesis. It is also found after the ingestion 
 of certain irritating medicines. 
 
 Pus. Pus is present, if at all, in a sediment. Pour 
 the urine from the sediment; add to the sediment a piece 
 
 77 
 
of caustic soda or potassa, and stir. If pus is present it 
 will turn from white to green, and become vitreous, 
 denser, and finally an adherent mass. No other sub- 
 stance produces this reaction. If only a little pus is 
 present it will change to a mucilagenous fluid instead of 
 an adherent mass. Pus cells seen under the microscope 
 are twice as large as blood corpuscles, and have a gran- 
 ular exterior. 
 
 Upon agitation of a specimen of urine containing pus, 
 the pus is uniformly diffused through the urine, giving 
 it an opaque appearance. It sinks to the bottom quickly 
 as a pale yellow or greenish white sediment. If albu- 
 men precipitates with the usual tests from the urine with 
 the sediment diffused, preserve the precipitate ; allow 
 the sediment in the urine to settle; pour off the super- 
 natant urine and test it and the sediment separately for 
 albumen. Compare the quantity obtained in the three 
 tests — medium quantity in the first ; maximum quantity 
 in the last ; minimum quantity in the second, if pus is 
 present. 
 
 Pus is present in the urine in abscess of the kidneys, 
 bladder, or contiguous structures, and sometimes after 
 destructive inflammation of these organs. 
 
 The writer observed large quantities of pus persisting 
 in a patient with interstitial nephritis, who was an ex- 
 cessive cigar and cigarette smoker. The pus would be 
 absent if he abstained from smoking for a time, but 
 immediately recurred as soon as the smoking was re- 
 sumed. 
 
 Mucus is not easily detected in urine. In excess it 
 is a colorless deposit, which does not mix readily with 
 the urine, but is poured from the vessel like syrup, and 
 is ropy or tenacious. 
 
 It may be precipitated with alcohol and tincture of 
 iodine, or with acetic acid in a solution of potassium 
 iodide. 
 
 It is present in catarrhal conditions of the urinary ap- 
 paratus, and sometimes during pregnancy. 
 
 Bile. Add to a specimen of urine one-third its bulk 
 of the potassium hydrate solution. Then slowly add 
 hydrochloric acid in excess until the alkalinity is entirely 
 neutralized. If bile is present the mixture turns to a 
 
deep emerald green ; if no bile is present it is colorless. 
 The color of urine when bile is present varies from a 
 dark yellow to brown, and leaves a stain on linen. 
 
 Bile is found in the urine in structural diseases of the 
 liver, and at times in temporary disorders of that organ. 
 
 ANIMAL URINE. 
 
 In the analysis of the urine of animals, the student 
 must be familiar with all the methods described in the 
 analyses of human urine, as the tests in either case are 
 the same. 
 
 Man is an omnivorous cmimal, and only differs from 
 the beast of that class in habits and intellectuality. 
 Because of the influence of the mind, and the superior 
 intelligence of man ; because of worry, anxiety, and 
 nerve shock; because of physical habits and social cus- 
 toms, he is subject to diseases which are not found in 
 the lower animals. Yet, all the constitutional diseases 
 of these animals have their congeners in the disorders 
 of mankind. 
 
 A perfect knowledge of the methods of the analysis 
 of urine will render the veterinarian pre-eminently su- 
 perior in the ability to diagnose and treat, not only 
 kidney diseases, but the constitutional disorders of the 
 lower animals. 
 
 Taking into consideration the urine of all animals, 
 wild and domestic, we find interesting differences, as 
 well as great similarity. All urines are not liquid. 
 Many animals, and fowls, have no urinary bladder, the 
 ureters opening into the rectum. In these cases, the 
 urine is solid. The urine of serpents is a solid mass, vary- 
 ing in size from that of a pea to a rounded mass two 
 and one-half or three inches in diameter. The urine of 
 fowls is solid. Guano is almost exclusively the urine of 
 the sea fowl. All insects deposit solid urine. While these 
 facts are true, about the only marked differences in these 
 urines is the absence of water. If the urine of insects, 
 reptiles and fowls be examined in comparison with that 
 of domestic animals and man, many of the same con- 
 stituents will be found in all. There are many striking 
 resemblances. The sodium and potassium phosphates, 
 certain ammonium compounds, sodium chloride, urea 
 
 79 
 
and hippuric acids and their salts are all very common 
 constituents. We, however, need study liquid urine 
 only. 
 
 The food of animals determines, to a certain extent, 
 the character of their urine. The urine of carnivorous 
 animals is rather light colored, clear, without sediment, 
 has an acid reaction, due to the presence of a large 
 quantity of uric acid (which is not found in the urine of 
 herbivora), and to phosphoric acid, represented by the 
 phosphates. The urine changes as the food changes. 
 The urine of many pet dogs presents all the peculiari- 
 ties of that of the omnivora. 
 
 The urine of omnivora we have described in our de- 
 scription of human urine. The urine of herbivorous 
 animals is the darkest of the three, and deposits a sedi- 
 ment on cooling. It is strongly alkaline because of the 
 carbonates of the alkalies. It contains no uric acid, 
 and no phosphates. This fact accounts, to an import- 
 ant extent, for its alkalinity, as it is the phosphoric and 
 uric acids which causes the acid reaction of other urine. 
 Herbivorous urine contains an excess of the carbonates, 
 and hippuric acid, which are absent in the urine of car- 
 nivorous animals, and present only in small quantity in 
 omnivora. The alkaline and earthy phosphates are 
 present in large quantities in the urine of carnivorous 
 animals. 
 
 While these differences appear in the urine of differ- 
 ent animals, we find great variations in the urine of the 
 same animal as the quality and quantity of food and 
 drink changes ; as he is active or passive ; as he is af- 
 fected by the changes in habit, climate, and various 
 other influences. 
 
 In quantity, the horse passes from 43 to 56 English 
 pints of urine in 24 hours, with a specific gravity vary- 
 ing from 1032 to 1050 The specific gravity of the urine 
 of cattle ranges from 1032 to 1042 , that of swine, from 
 1010 to 1012 ; that of goats and sheep, from 1007 to 
 1010. 
 
 There is probably the same relative proportion of 
 solids in comparison with the weight of the animals, 
 eliminated by all of these animals, but those solids are 
 eliminated in a larger or smaller percentage of water. 
 
In testing animal urine, the same apparatus may be 
 used as in the testing of human urine, except that larger 
 test tubes (6 inch) should be used. A few important 
 differences between the normal and abnormal constitu- 
 ents of human and animal urine may be studied. 
 
 Urea, in the urine of horses and cattle, is excreted 
 in a larger proportion than in man. If a half test tube 
 of urine be treated with one- third its bulk of nitric acid, 
 the crystals of nitrate of urea precipitate to one-fourth 
 or one-sixth the bulk of the urine, on cooling. The 
 urine of the dog is generally quite rich in urea. 
 
 Urea is found in the urine of all animals, and as it rep- 
 resents the excess of nutrition, as well as tissue meta- 
 morphoses, artificially fed domestic animals are liable to its 
 accumulation in the system, resulting in a condition of 
 uremic poisoning, with all its influences upon the nerv- 
 ous system — spasm, paralysis, dyspnoea, delirium, coma 
 and death. 
 
 In the disease in horses known as Azoturia, the symp- 
 toms are, to a large extent, those of uremic poisoning. 
 At the same time a great excess of urea is found in the 
 urine. In the uremic poisoning of man, there is a 
 retention of the urea in the blood, there being but very 
 little found in the urine. In azoturia, the probabilities 
 are that there is an enormous excess in the blood, even 
 after the kidneys are doing their very utmost to elimin- 
 ate it. That this excess is augmented by immediate 
 exercise and rapid tissue waste, and as a result violent 
 uremic intoxication suddenly occurs, while the urine is 
 loaded with urea. 
 
 Uric Acid is sometimes found in exceedingly small 
 quantities in the urine of herbivorous animals, although 
 normally absent. It is excessive in the urine of dogs 
 and cats, even when these animals are fed upon mixed 
 diet. While uric acid is absent from the urine of 
 nursing infants, it is found present in tlie urine of suck- 
 ing calves. (Wohler.) At the same time hippuric acid 
 is entirely absent in the calf, but is present in the infant. 
 (Harley.) 
 
 Uric acid calculi are formed in dogs. 
 
 Hippuric acid is the normal acid of the urine of 
 herbivorous animals. It is present in the proportion of 
 
10 or 12 parts per thousand in the urine of horses, and 
 absent in carnivora. 
 
 Horses highly fed without exercise pass a much less 
 quantity of hippuric acid than when at work, although 
 this statement is opposed by good authorities. In mak- 
 ing comparisons, it is difficult to estimate all influences. 
 In all conditions of imperfect aeration of the blood, 
 hippuric acid is found in increased quantities. It is 
 a normal constituent of the blood of herbivorous ani- 
 mals. 
 
 Chloride of Sodium is essential to the nutrition of 
 herbivorous animals. Wild cattle, in some parts of 
 Africa, travel hundreds of miles to drink at salt springs. 
 It increases the functions of the body, and conduces to 
 accumulation of fat and preserves health. Its presence 
 in the urine, when not given in excess, is an index to the 
 physical condition of the animal. 
 
 Albumen. Inflammation of the parenchyma of the 
 kidneys is by no means as common in the lower animals 
 as in man, because with man alcohol and tobacco are 
 active and common causes. Albumen will be found in 
 the urine of animals after hemorrhage into the urinary 
 passages from any cause, as from direct injury or violent 
 muscular exertion. It is found in the "red water" in 
 cattle, because of the presence of blood serum and 
 broken down blood corpuscles. It occurs after injury 
 to, or diseases of, the brain or spinal cord, and from 
 the absorption of certain irritating substances into the 
 blood, such as turpentine, cantharides, etc. If actual 
 inflammation of the kidneys does occur, the pathology is 
 the same as in human urine, with the constant presence 
 of albumen. 
 
 Mucus and Pus. These substances are found in 
 larger quantities, proportionately, in the urine of ani- 
 mals than in that of man, and may be recognized by the 
 same tests. 
 
 The mucus lining of the pelves of the kidneys, or of 
 the ureters, bladder and urethra, may deposit very large 
 quantities of clear, transparent ropy mucus. Mucus 
 from the vagina is often found in the urine after partu- 
 rition. Mucus in excess will sometimes be found in the 
 urine of horses after violent muscular exertion. 
 
Pus is found when there is excessive irritation of the 
 urinary apparatus, or after inflammation of these parts 
 as described. 
 
 Carbonates. — The carbonates of the alkalies potas- 
 sium, sodium, and ammonium, are soluble in water, and 
 do not readily precipitate; but the earthy carbonates are 
 quite insoluble, and the carbonate of calcium will pre- 
 cipitate from the urine of the horse, in health, a short 
 time after it has been passed, in the form of an earthy 
 powder or chalky sediment. It decomposes readily upon 
 the addition of the mineral acids, giving off large quan- 
 tities of carbonic acid gas. (C0 2 ). 
 
 For this reason acetic acid should oe used in these 
 tests instead of nitric acid. 
 
 Ordinary calculi in the horse are largely formed of this 
 substance. 
 
 In calcareous degeneration, or ossification of a part or 
 organ in the animal body, the deposit is largely of the 
 carbonate of lime, which in these cases is in excess in the 
 blood 
 
 Phosphates. — The phosphates are not normally pres- 
 ent in any appreciable quantity in the urine of herbivor- 
 ous animals. 
 
 But certain foods will cause their appearance in large 
 quantities, when they may be precipitated upon the mu- 
 cous surfaces of the bladder and urethra, or upon the 
 external parts. Their presence gives rise to irritation of 
 the bladder and urethra, and may lead to an inflamma- 
 tion of those organs and the kidneys. They are found 
 in excess also in certain inflammatory diseases, either of 
 an acute or chronic character. 
 
 Oxalic Acid. — This substance is more often found 
 in the urine of domestic animals than in man. It is 
 deposited in the form of the insoluble oxalate of lime, 
 when those substances are eaten which contain oxalic 
 acid in abundance, or when from any cause there is a 
 fault in tissue metamorphosis — when the waste products 
 are not properly converted into urea. The formation of 
 oxalic acid within the body seems to be an intermediate 
 stage of tissue change, m the process of the conversion 
 of nitrogenous effete matter into urea, which occupies 
 the highest position m the scale. The process of change 
 
being interfered with, the oxalic acid remains, and is 
 converted into soluble and Insoluble oxalates. 
 
 Tests. — If oxalic acid is suspected in the urine, the 
 addition of acetic acid to urine containing the carbonate 
 of lime will allow the characteristic crystals of calcium 
 oxalate to precipitate alone. If the lime salts are not 
 present, a solution of calcium chloride may be added 
 after the acetic acid, which only serves to prevent phos- 
 phates from being precipitated. These crystals are in- 
 soluble in water, liquor potassa, or acetic acid, but will 
 dissolve immediately in nitric acid without effervescence. 
 Familiarity with the microscopical appearance of the 
 crystals is essential. They assume four distinct forms : 
 The regular octohedra, the dumb-bell, the irregular disc, 
 and the diamond-shaped crystals. 
 
 There is not much danger of mistaking them, as only 
 tri-calcium phosphate and uric acid is likely to be pre- 
 cipitated under the same circumstances, and with these 
 we are familiar. 
 
 Sugar is not common in the urine of herbivorous ani- 
 mals. They are not often subject to diabetes mellitus ; 
 but dogs and other omnivorous animals will excrete 
 sugar in large quantities under certain circumstances. 
 The tests are the same as in human urine. 
 
INDEX. 
 
 ABSOLUTE ALCOHOL,46. 
 Absolute weight, 3, 
 Acetic acid, 47. 
 Acetous fermentation, 47. 
 Acetyl hydrate, 47. 
 Acids, definition of, 9. 
 
 Structure of, 8. 
 
 Arsenious, 27. 
 
 Hippuric, 73. 
 
 Hydrofluoric, 22. 
 
 Hydriodic, 26. 
 
 Hydrocyanic, 60. 
 
 Hydrobromic, 25. 
 
 Hydrochloric, 23. 
 
 Nitric, 20. 
 
 Nordhausen, 32. 
 
 Oxalic, 61. 
 
 Prussic, 60. 
 
 Sulphovinic, 48. 
 
 Sulphurous, 30. 
 
 Sulphuric, 31. 
 
 Uric, 73. 
 Air, 17. 
 Albumen in Urine, 74. 
 
 In Animal Urine, 82. 
 Alcohol, 46. 
 Alkahimides, 10. 
 Amides, 10. 
 Amines, 10. 
 Ammonia, 18. 
 Ammonium Compounds, 19. 
 
 Bromide, 20. 
 
 Carbonate, 19. 
 
 Chloride, 19. 
 
 Bydrate, 19. 
 
 Iixlide, 20. 
 
 Nitrate, 19. 
 
 Sulphate, 19. 
 Ampere's Law, 10. 
 Amorphous Carbon, 43. 
 Analytical Chemistry, 51. 
 Analysis (if I 'line, 69. 
 Animal Charcoal, 43. 
 Animal Urine, 79. 
 Antimony, 28. 
 
 Tests for, 64. 
 
 Antozone, 14. 
 Apparatus, 51. 
 Apparent "Weight, 3. 
 Aquafortis, 20. 
 Arsenic, 27. 
 Arsenic, Tests for, 61. 
 Arsenious Oxide, 27. 
 Atom, 5. 
 
 Atomic Weight, 5. 
 Atmosphere, 17. 
 Attractions of Matter, 3. 
 Atropine, Tests for, 59. 
 Aurum, 40. 
 Azote, 16. 
 
 BASES, definition of, 9. 
 Structure of, 8. 
 BerthoTet's Law, 52. 
 Bile in Urine, 78. 
 Binary Molecules, 7. 
 Bismuth, 41. 
 
 Subnitrate, 41. 
 Bittern, 25. 
 Black lead, 43. 
 Blende, 29. 
 Blood in Urine, 77. 
 Bone Black, 43. 
 Bromine, 23. 
 Bromoform, 49. 
 
 CADMIUM, 38. 
 Calcium, 35. 
 Calomel, 42. 
 Carbo-animalis, 43. 
 Carbo-ligni, 43. 
 Carbon, 42. 
 
 Dioxide, 42. 
 Carbonic Acid Gas, 44. 
 Carbonous Oxide, 44. 
 Carbon Plates, 44. 
 ('ail urn Points, 44. 
 Carbonates in Animal Urine, 
 
 83. 
 Charcoal, 43. 
 
 Chemistry, Definition of, 2. 
 Chemism, 3. 
 
Chemical Elements (Table), 4. 
 Chemical Solution, 52. 
 Chlorine, 22. 
 Chloride of Gold, 40. < 
 
 Of Gold and Sodium, 40. 
 
 Of Sodium, 24. 
 
 Of Sodium in Animal 
 Urine, 82. 
 Chlorides in Urine, 71. 
 Chloroform, 48. 
 Coal, 43. 
 Cobalt, 39. 
 Cohesion, 3. 
 Coin Silver, 39. 
 Coke, 43. 
 Common Salt, 24. 
 Compound, A, 5. 
 
 Molecule, A, 6. 
 Copper, 37, 
 Cryolite, 22. 
 Cuprum, 37. 
 
 DECANTATION,53. 
 Desiccation, 53 
 Diamond, 53. 
 Diffusion, 17. 
 Dilute Alcohol, 47. 
 Dioxide of Carbon, 44. 
 Distillation, 53. 
 Di-sulphuric acid, 32. 
 
 ELECTKO-CHEMISM, 7. 
 Elements, 5. 
 Ether, 48. 
 Ethyl Oxide, 48. 
 Equivalence, 6. 
 Evaporation, 53. 
 
 FERMENTATION, 46. 
 Eiltration, 53. 
 Fluorine, 22. 
 Fluoroform, 49. 
 Eluor Spar, 22. 
 Formula, Definition of a, 7. 
 Formyl Iodide, 49. 
 Fusion, 52. 
 
 GALENA, 29. 
 Gas, 3. 
 Gas Retort Carbon, 43. 
 General States of Matter, 3. 
 
 "Working Rules, 54. 
 Glycerine, 50. 
 Gold, 40. 
 
 Graham's Law, 18. 
 Graphite, 43. 
 Gravitation, 3. 
 
 HALOGENS, THE, 22. 
 Haloid Salts, 22. 
 Hippuric Acid, 74. 
 
 In Animal Urine, 81. 
 Hydrocarbons, 48. 
 Hydrocyanic Acid, Tests f or,60 
 Hydrobromic Acid, 25. 
 Hydrochloric Acid, 23. 
 Hydrofluoric Acid, 22. 
 Hydriodic Acid, 26. 
 Hydrogen, 12. 
 
 Bromide, 25. 
 
 Per Oxide, 13. 
 
 Sulphate, 31, 
 
 Sulphite, 29. 
 Hyponitrous Oxide, 20. 
 
 INCINERATION, 53, 
 1 Indestructibility of Mat- 
 ter, 3. 
 Inorganic Chemistry, 2. 
 Iodine, 26. 
 
 Iodide of Mercury. 42. 
 Iodoform, 49. 
 Iron of Leonarto, 12. 
 Isomorphism, 22. 
 Ivory Black, 43. 
 
 J 
 
 ET, 43. 
 
 T^UPFERNICKEL, 38. 
 
 LABORATORY COURSE 
 51. 
 Laughing Gas, 20. 
 Lead, Tests for, 65 
 Linking Elements, 8. 
 Liquids, 3. 
 
 MAGNESIUM, 35. 
 Mass, 2. 
 Matter, 2, 
 
 Mercuric Chloride, 42. 
 Mercurous Chloride, 42. 
 Mercuric Iodide, 42. 
 Mercurous Iodide, 42. 
 Mercury, 41. 
 
 Test for, 66. 
 Mild Chloride, 42. 
 Mispickle, 27. 
 Molecules, 6. 
 Monoxide of Carbon, 44. 
 Morphine, Tests for, 58. 
 Mother of Vinegar, 47. 
 Mucus in Urine, 78. 
 In Animal Urine, 82. 
 
Mycoderrua Aceti, 46. 
 
 'AMINGof COMPOUNDS, 
 
 N' 
 
 Ternary Compounds, 9. 
 Nascent State, The, 13. 
 Natrium, 34, 
 Natural Science, 2. 
 Nickel, 38. 
 Nitric Acid, 20 
 Nitrogen, 16. 
 Nordhausen Acid, 32. 
 
 OIL OP VITRIOL, 31. 
 Organic Chemistry, 42. 
 Organic Substances, 46. 
 Orpiment, 27. 
 Oxalic Acid, Tests for, 61. 
 In Animal Urine, 83. 
 Oxygen, 13. 
 Ozone, 14. 
 
 PARAFFINE SERIES, 48. 
 Pencillium Glaucum, 46. 
 Peroxide of Hydrogen, 15. 
 Phenol, 50 
 Phosphorus, 33 
 
 Tests for, 67. 
 Phosphates in Urine, 71. 
 Physical Science, 2. 
 Physics and Chemistry, 2. 
 Plastic Sulphur, 29, 
 Platinum, 43. 
 Plumbago, 43. 
 Poison, 56. 
 
 Polythionic Series, 31 
 Potassium, 34. 
 
 Carbonate, 34; 
 
 Hydrate, 34. 
 
 Nitrate, 34. 
 Preliminary Work, 54. 
 1 'i ussic Acid, Tests for, 59. 
 Pus in Urine, 77. 
 
 In Animal Urine, 82. 
 Pyroligneous Acid, 47. 
 
 Q 
 
 UICKSILVER, 41. 
 
 RADICAL, A, 10. 
 l!c;iction, 52. 
 Reagent, 62. 
 
 SALTS, 8. 
 Definition of, 9. 
 
 Science, 2. 
 Silver, 39. 
 
 Simple Molecule, 6. 
 Simple Solution, 52. 
 Sodium, 34. 
 
 Chloride, 24. 
 Solvent, 52. 
 Specific Weight, 3. 
 Stannum, 39. 
 Stibnite, 28. 
 Stoichometry, 11. 
 Strychnine, Tests for, 57. 
 Sublimation, 53. 
 Sugar in Urine, 75. 
 
 In Animal Urine, 84. 
 Sulphovinic Acid, 48. 
 Sulphates in Urine, 72. 
 Sulphur, 28. 
 Sulphuric Acid, 31. 
 
 Ether, 48. 
 Sulphuretted Hydrogen, 29. 
 Sulphurous Oxide, 29. 
 Symbol, 5. 
 
 TARTAR EMETIC, 28. 
 Ternary Molecules, 7. 
 Theoretical Chemistry, 1. 
 Tin, 39. 
 
 Torula Cerevisise, 46.. 
 Toxicology, 56. 
 Tri-oxide of Arsenic, 27. 
 
 UREA, 72. 
 In Animal Urine, 81. 
 Uric Acid, 73. 
 
 In Animal Urine, 81. 
 Urine, Human, 69. 
 Of Animals, 79. 
 
 VINEGAR, 47. 
 Vinic Alcohol, 46. 
 
 WATER, 15. 
 Water Type, 8. 
 Water, Tests for Impuriti 
 
 in, 68. 
 Weight, 3. 
 White Arsenic, 27. 
 
 ZINC, 38. 
 Carbonate, 38. 
 Oxide, 38. 
 
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