NEW BOOKS Applied Colloid Chemistry. General Theory. B y Wilder D. Bancroft. 20 X 14 cm; p p . viii 343;. ATew 170rk: iMcGraw-Hill Book Company, Inc., 1921. Price : $3.00.-In the far off days when the earth was comparatively young, the present reviewer remembers Professor Bancroft as a pioneer in the theory of heterogeneous equilibria and a virile revolter from the elegant triflings of the dilute solutionists. From those historical days up to the present time, there has always been a delightful quality of vigor and freshness about his work-something of the Norse Viking blowing in with the North wind on gentle shepherds in mellow valleys, or of Border Chieftains riding in the night with two-handed claymores. A quality, in short, of original strength, pleasantly spiced with humor and perhaps just a dash of original sin. Are not the pages of a certain well-known American scientific Journal strewn with the literary corpses of dull authors, and of the many who have erred in the fieldsof photochemistry, emulsions, adsorption, and colloids? Professor Bancroft’s many and excellent qualities are well excrnplified in the present volume. There is something titanic about it. Read this from first sight colloid chemistry may not seem to be an the Introduction :-“At important! branch of chemistry, either theoretically or technically; but this opinion changes when we consider that a knowledge of colloid chemistry is essential to anybody who really wishes to understand about: cement, bricks, pottery, porcelain, glass, enamels; oils, greases, soaps, candles; glue, starch, and adhesives; paints, varnishes, lacquers; rubber, celluloid, and other plastics; leather, paper, textiles; filaments, casts, pencils, and crayons; inks; roads, foundry cores, coke, asphalt; graphites, patines; zinc, phosphorus, sodium, and aluminum; contact sulphuric acid, hardened oils, etc.; beer, ale, and wine; cream, butter, cheese, and caseine products; cooking, washing, dyeing, printing; ore flotation, water purification, sewage disposal; smoke prevention; photography; wireless telegraphy; illuminants; comets; pharmacy;. physiology. I n other words colloid chemistry is the chemistry of every-day life.” There you have the true Napoleonic glance. A s Mallock said: “Him not the splintered lightnings, nor the roll Of thunders daunted, undismayed, his soul Rose, and outsoared the thunder, plumbed the abyss, And scanned the wheeling worlds from pole to pole.” That the present volume surveys the whole field in a characteristically original fashion will be evident from the titles of the chapters, which are as follows :I. Adsorption of Gas or Vapor by Solid. 11. Adsorption of Vapor by Liquid, and of Liquid and Solid by Solid and Liquid. 111. Adsorption from Solution. IV. Surface Tension-Brownian Movements. V. Coalescence. VI. Preparation of Colloidal Solutions. VII. Properties of Colloidal Solutions.
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A Dictionary of Applied Chemistry. By Edward Thorpe. Vol. I. Revised edition. 23 X 16 cm; p p . vi 752. New York: Longmans, Green and Co., 1921. Price: $zo.oo.-The preceding edition was got out with commendable promptness and apparently the same plan is to be followed with this one. The publishers, Messrs. Longmans, Green and Co., write that they expect to issue the second volume this summer and the subsequent ones a t intervals spread over the next two years. That programme is all that anybody could ask. The publishers also state that “the entire work has been carefully revised in the light of recent developments. Many new articles have been added and certain of the existing articles have been recast or wholly rewritten. Extensive additions have been made to subjects of technical importance, such as sulphuric acid, nitric acid, chlorine, alkali manufacture, synthetic production of nitrogen products, explosives, the synthetic coloring matters, the metallurgy of the commercially important metals, oils, fats, glycerine, etc. New articles appear on the natural organic coloring matters, and on the relation of color to chemical constitution. Fine chemicals have received special attention,
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all the pharmacological articles have been revised, alkaloids and synthetic drugs have been treated a t greater length and much new matter relating to them has been added.” Among the interesting topics in this volume are: acetic acid, acetone, acetylene, acidimetry, aconite, acridine dyes, actinium, adhesives, adrenaline, aerated waters, agate, alcohol, aldehyde, alizarine, aluminum, alums, amalgam, amber, amino-acids, ammonia, analysis, aniline, anthrocyanins, anthracene, antimony, argon, arsenic, asphalt, assaying, atmosphere, atomic weights, azines, azo dyes, bakelite, baking powders, balance, balata, balsam, benzene, bismuth, bleaching, blood, boiler incrustations, bone, boron, brandy, bread, brewing, bromine, butter, cadmium, caesium, caffeine, calcium. Under acidimetry, p. 59, is given a table based on Thomson’s work. It would have been better t o have supplemented this with a table of pH values. The text of this article is unduly long because the remarks are kept vague. The article on adhesives, p. 76, is probably as good a one as could be written; but it brings out clearly our complete ignorance of the subject except on the empirical side. Under mineral waters, p. 83, the reviewer was interested to read that “the popular demand for a liquid which shall retain its frothy head for some time after it has left the bottle has led t o the manufacturers frequently adding an extract of quillaia bark or other preparation of saponin, sold under the name of ‘foam heading,’ etc. Such an addition is more necessary in liquids containing saccharin than in all-sugar beverages, which froth more with the carbon dioxide.” Under balata is the statement, p. 529, that “in physical properties and chemical composition, balata resembles true guttapercha, for which it is the best natural substitute, and it is of interest in this connection that the trees yielding it belong to the same order as the trees which furnish guttapercha.” Some of the rubber chemists say that the hydrocarbons of balata and guttapercha are identical and the reviewer would have welcomed a more definite stand on this point. On pp. 11-16 there is a misprint in the headings: of acetanilide for acetic acid. Most of the articles are brief; but the editor has shown judgment in the matter. The longest article, as might, have been expected, is the one on analysis, and the next longest is on the azo coloring matters. Others which run over four pages are: acetals, acetic acid, acetylene, acidimetry, aconitine, acridine, dyestuffs, aerated waters, alcohol, aldehyde, alizarine, aluminum, alums, ammonia, anthrocyanins, anthracene, antimony, assaying, atmosphere, azines, balance, barberry, barium, benzaldehyde, brewing, bismuth, bleaching, boi!er incrustations, bone oil, brandy, Brazilwood, brewing, bromine, butter, butyl, calcium. Most of these arc what one would expect; but the reviewer was surprised to find barberry in this list and he had not hitherto appreciated the importance of bone oil. It is a great pleasure to find that a new edition of this important work is called for a t the present time and that the need can be filled so promptly. Both of these things are very encouraging in the midst of the business depression. Wilder D . Bancroft Handbuch der anorganischen Chemie. By R. Abegg and F. Auerbach. I , Second section. 25 x 17 cm; pp. xiii 1072. Leipzig: S.
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Hirsel, 1921. Price: paper, 140 marks; bound, 170 marks.-Prom the preface it appears that work on this volume was begun again in 1918, which shows a promptness in getting back to work after the war that many of us may envy. The elements discussed in this volume are chromium, molybdenum, tungsten, and uranium. There are special chapters on the colloid chemistry of these metals and a very interesting one on what the authors call heteropoly acids, meaning phosphomolybdates, etc. The work done in getting out such a volume is enormous and the value to the chemist is correspondingly great. From a superficial reading the only thing that the reviewer missed was some statement about the ruby turning green when heated. Each man will get different things from the volume according to his especial tastes. Among the things that interested the reviewer were: the effect of adsorption on the atomic weight of chromium, p. 6; the readiness with which chromic oxide changes to chromate when heated in presence of a trace of alkali, p. 8; the adamantine lustre of crocoite, p. 2 2 ; the hardness of chromium, pp. 30, 433; the reduction of hydroxylamine to ammonia by chromous salts, p. 51; the more recent data on the tin-chromium cell, p. 53; the pearly lustre of chromous fluoride, p. 56; the surface color of chromic bromide and oxide, pp. 102, 120; the electrolytic oxidation to chromate with lead peroxide anode, p 292; the effect of ultra-violet light on chromic acid solutions; p. 315, the equilibrium relations for chromium trioxide, p. 327; the color changes of lead chromate, p. 389; the problem of chromium dioxide, p. 398; the perchromates, p. 415; molybdenum blue, p. 626; Tammann’s work on the physical properties of metals, p. 728; and tungsten blue, p. 821. The question of the tungsten bronzes is an interesting one, pp. 834-837. One great trouble is the difficulty of analysis. It seems to the reviewer in his cheerful ignorance of the subject that most of this might be avoided by working synthetically. One could start with weighed amounts of WOZ, WOS and NanO; let them come to equilibrium; and examine for homogeneity. The weak point in this is, of course, that the mixtures might not reach equilibrium; but we do not yet know that and certainly this line of attack is more promising than the analytical one, which has broken down. . In the case of the phosphomolybdates, phosphotungstates, etc., it has been suggested that they are due in part to adsorption; but nobody seems to have tried the simple experiment of dialyzing some of these solutions. Nobody has yet answered the question why the ruby is red. The most plausible explanation is that there are two forms of chromic oxide just as we know that there are two forms of chromic chloride; but the application of Werner’s views to the ruby has not yet been made in any satisfactory way. One might go on indefinitely, pointing out interesting things found in, or suggested by, this book; and others would make similar but entirely distinct lists. This would merely be giving additional proofs of what is already obvious, Wilder D . Bancroft that the book is a monumental piece of work. Elementary Chemistry for Coal-Mining Students. B y L. T . O’Shea. X 14 cm; p p . x i f 319. New York: Longmans, Green and Co., 1920. Price: $3,oo--In the preface the author says: “For many years I have delivered both popular and more or less systematic courses of lectures to deputies and other 20
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workers in coal mines, students who have little or no knowledge of chemistry but are kcenly desirous of learning something of the subject which may be useful to them in their daily occupation. The ordinary text-book of chemistry does not meet their requirements, for it contains much that it is unnecessary for them to study, and much that it is desirable for them to know is not to be found in it. The present work has been prepared with the object of meeting the wants of these as well as of other students of coal-mining. It is really a compilation of those parts of chemistry, pure and applied, that are cognate to the coal-mining industry, and does not pretend to be a textbook of chemistry.” The chapters of special interest to the coal-mining students are entitled: flame and the safety lamp; coal; by-products and their recovery; explosives; explosions in gases. The reviewer turned a t once to the chapter on flames and was a bit disappointed to find on p. 130 that “to produce a flame it is necessary to have two gases in an active state of chemical interaction which will produce sufficient heat to raise the burning gas to a temperature a t which it will give out light, or, in other words, becomes incandescent. Flame then is defined as a gas raised to incandescence by chemical interaction. All flames produced in air are caused by the chemical interaction of combustible gases with the oxygen of the air.” More successful are the paragraphs from the chapter on explosions in gases, p. 261. “In experiments made for the Prussian Fire-Damp Commission it was estimated that from 10 to 13 feet of flame are produced when a blown-out shot of half a pound of gunpowder is fired into gas-free air from a hot-hole stemmed with clay, and that the flame increases to 16 feet when the hole is stemmed with stone dust and coal dust, while if coal alone is used the flame increases to 31 to 52 feet. I n experiments on flameless explosives made by the North of England Institute of Mining Engineers it was proved that considerably more flame was produced when shots were fired into dusty atmospheres than when fired into gaseous atmospheres without dust. “When a gas explosion takes place it may be compared with a blownout shot, and if i t occurs in a dust-free atmosphere the amount of flame produced is that due to the volume of gas that is burnt; but if the air be charged with coal dust the heat of the flame causes some of the dust to distill, with the production of gases which take fire and add to the volume of flame, while the atmosphere becomes charged with red-hot particles of coke dust. “By far the most important effect is the manner in which coal dust will carry on a gas explosion beyond the limits of the gas-fouled areas. Many gas explosions have taken place which have traversed very considerable lengths of roadways, in some cases amounting to thousands of yards. The extent of the explosion in these cases is so great that it is difficult to account for it by the explanation that the atmosphere throughout the course of the explosion was fouled with gas in sufficient quantity to form an explosive mixture. If this were so, there would be evidence of alarm all along the course, but in most cases this is wanting. It is also improbable from the fact that generally the roadways are main intake air-ways, which could only be fouled by gas coming from some sudden outburst. “These main intakes are generally dry and dusty with coal dust which forms tolerably thick layers on the roadways, timbers, and walls, and in its
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finest form floats in the air itself. The dust in such an atmosphere produces just the conditions necessary to continue an explosion of gas when started, for, when the explosion takes place, the flames not only shoot forward into the dusty atmosphere and ignite the dust in suspension, but the vibrating masses of burning gas blow up clouds of dust in front of them which become ignited, and they in turn blow up and ignite further clouds and the explosion is continued along the dusty roads as long as there is coal dust in sufficient quantity capable of being blown up into the air by the force of the exploding mass. “In these explosions it is a well-known fact that their course is stopped by roadways that are wet, from which the dust cannot be blown up in clouds, or roadways dusty with a non-inflammable stone dust, or coal dust largely mixed with stone dust, which proves that coal dust and not gas causes the propagation of the explosion. If the explosion were continued in an atmosphere fouled with gas along its whole course the wetness of the coal dust or the presence of stone dust would make no difference to the explosion, which would continue so long as there was gaseous fuel, and only the absence of gaseous fuel would stop it, whereas in an explosion propagated by coal dust it is the absence of inflammable dust Wilder D . Bancroft that stops the explosion.” Applied Electrochemistry and Metallurgy. B y Charles F. Burgess, H . B . Pulsifer and Benjamin B. Freud. 21 X I? cm; pp. 198. Chicago: American Technical Society, 1920. Price: $2.5o.-Professor Burgess has written the section on applied electrochemistry and Messrs. Pulsifer and Freud the section on metallurgy. The scope of the book is given in the introduction. “The principles of Electrochemistry are almost as old as the science of electricity itself. The phenomenon of electrolysis was discovered in 1800, and its laws were experimentally determined by Faraday in 1833; again the electrolytic cell, with its simple electrodes and conducting liquid, was very early used t o accomplish the dissociation of chemical compounds in the same manner as it is now used in chemical industries; the electric furnace was really discovered almost simultaneously with the arc lamp and in its essentials is identical with it. “The cheapening of electrical power and the increased use of the products involved have been largely responsible for the progress along these lines, and today, the preparation of electrolytic copper is a great industry; hydrogen and oxygen gases are now obtained by the electrolytic decomposition of water; and the method of electrolyzing fused aluminum oxide has brought the price of aluminum to a practical basis. Again, by means of the electric furnace, several highly resisting chemical reductions have been accomplished and methods have been perfected for the manufacture of calcium carbide, silicon products, carborundum, graphite, and steel. “The same years that have seen such remarkable progress in Electrochemistry, have also witnessed uncommon development in that closely related artApplied Metallurgy. The great steel works of the country, the coal and ironmining industries, ship-building, ordnance manufacture, sky-scraper erections and hundreds of other fields, are hugely interested in what the skilled metallurgist discovers. Metallurgy and Electrochemistry alike attract studentsfollowing through processes in these arts a t times attains the interest of a novel.
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“Finally, when by the aid of intense electrical discharges in air, even the nitrogen of the atmosphere is made available for our use, the results seem to approach the miraculous. To think of the world’s supply of nitrates being augmented from the very atmosphere itself seems more like a dream of a Jules Verne or a Wells, than an actual twentieth century accomplishment. “All of these scientific marvels are intensely interesting and the treatment has been made exceedingly practical by the authors. The material is written in a clear readable style and is designed to appeal to both the trained engineer and the layman. It is the hope of the publishers that a study of this volume may widen the acquaintance of many readers with this branch of industrial electricity and stimulate their interest in the general scientific development of the world.” It is intended to be a popular book and it gives a sketchy but fairly satisfactory presentation of the subject. The reviewer had supposed that in the Birkeland-Eyde process the air travelled through the disc of flame and not parallel Wilder D. Bancroft with it, p. 81. Die Schwimmaufbereitung der Erze. B y Paul Vugeler. 23 X 16 o 98. Dresden and Leipzig: Theodor Steinkopff, 1921. Price: 4 shillings, 4 pence.-The subject is treated under the general headings: historical sketch of the theories; the effective forces in ore flotation; the mechanism of the processes taking place in the ore-pulp; practical points of view for carrying out flotation rationally; account of the more important methods for examining ores and reagents; account of the more important methods in technical use. h’othing could be better than this programme and our interest is excited by the author’s statement that the German method of scientific study clears up matters in a way that is impossible by the Anglo-Saxon method of cut-and-try. Unfortunately the promise of the table of contents is not fulfilled in the text. The author is quite clear that the contact angle is a less important factor in ore flotation than adsorption; but we did not need a German to tell US that. There is a good deal about Werner’s co-ordination theory in the book but very little that is helpful in regard to ore flotation. There is no adequate discussion of the conditions under which froth is formed or is stable; there is no comparison of the Callow process with the orthodox ‘bubbles’ process; the question of soluble and insoluble frothing agents is not taken up seriously; there is no explanation why saponin kills flotation under ordinary conditions or why adding copper sulphate to the Tennessee zinc ore was beneficial. The author is very vague in his statements and about all that the reviewer has got out of the bbok is that ore to be treated by flotation should all pass a 60-mesh sieve and 75 percent of it should pass a 200 mesh sieve. The reviewer is inclined to believe that even that was found by a cut-and-try method and is not a triumph of German sagacity. The author believes that ore flotation may perhaps be superseded some day by differential sedimentation; but he does not go into details. Wilder D. Bancroft cna;
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students certain of the more important aspects of physical chemistry, together with accurate modern data which illustrate the applicability of its laws to the phenomena observed in the laboratory. It has been assumed that the student is familiar with inorganic and analytical chemistry, that he has had an adequate course in college physics, and that the simple processes of calculus are familiar to him. “NO attempt has been made to cover the whole of physical chemistry in a single volume; its most important topics have been treated a t such lengths as the size of the volume allows, and numerous references to recent periodical literature are included for those who would pursue any given topic further. “The limitations of the orthodox laws of physical chemistry have been emphasized more than is commonly done in beginning courses of physical chemistry. To this end the illustrative data have been carefully chosen from modern experimental work, in order to minimize the “experimental errors” which are so often used to conceal real deviations of a law from the facts it is intended to cxpress. A trusting belief in inadequate physical laws will only retard the scientific progress of a student, and weaken his faith in adequate laws; whereas a wholesome appreciation that physical chemistry is a n unfinished and growing science may stimulate thoughtfulness and research. The proper time to encourage a research attitude is in the very beginning of a student’s chemical career.” The chapters are entitled: introduction and determination of atomic weights; laws of gases; liquid substances; solids; solutions-ideal solutions; ionized solutes and electrical conductivity ; thermochemistry ; homogeneous chemical equilibrium ; heterogeneous chemical equilibrium; velocity of chemical reactions; physical properties and chemical structure; the periodic law; radiochemistry and radioactivity ; surface chemistry-colloids ; electrochemistryelectromotive force. There are a number of good things in the book: the diagram for gases, p. 25; the comparative table for internal pressures, p. 67; the diagram for Lhe change of atomic heat capacity with the temperature, p. 97; the half-tone for the X-ray patterns of sodium fluoride and sodium hydrogen fluoride, p. 104; the table for the hydration of ions, p. 182, though some reference to Bousfield should have been made ; the comparison of activity coefficients and conductance ratios, p. 183; the phase diagram for urethane, p 274. On p. 89 the author discusses Langmuir’s views on the spreading of oil on water and on p. 107 Langmuir’s ideas on adsorption. He might well have pointed out that Langmuir has deduced an equation for the adsorption isotherm on the explicit assumption that the adsorption layer is several molecules thick. On p. 118 the author fails to bring out that an aqueous solution saturated with sodium chloride will not be in equilibrium with a saturated solution of sodium chloride in alcohol. The relation is also not true if we substitute ether for alcohol though the error is much less On p. 156, under chemical reactions at the electrodes, the author italicizes the statement thak “the reaction requiring the lowest potential always takes place first.” This is true provided one knows how to interpret i t ; but there is no reference anywhere to overvoltage and it will be difficult for the student to see why cadmium should precipitate on platinum from an acidified cadmium sulphate solution. The reviewer was interested in a statement on p. 123. “The large errors in the pressure of carbon disulphide calculated
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by means of Raoult’s law when it is present in small proportion illustrate an important fact. Raoult’s law is a law for the vapor pressure of a solvent, and carbon disulphide is scarcely the solvent when its mol. Fraction is only 1- 0.885 = 0.115.” The reviewer is quite willing to accept this; but the definitions of solvent and solute should be adjusted to suit. The reviewer would also have liked to have seen a few remarks about volume concentration versus mass concentration and about heats of dilution. The author is quite explicit, page 175, as to the difficulty in regard to the change of the transference number with the concentration. “The transference number of an ion is the fraction of the total electricity carried by it through a solution. A table of such transference numbers for the positive ions in solution is shown in Table 71. It should be noted that these transference numbers change but little with the temperature, in spite of the large increase in equivalent conductivity at higher temperatures mentioned on page 178. This means that all ions increase their velocities a t about the same fractional rate as the temperature is raised, but there is a slight change in ionic velocity ratio with concentration, which lacks an explanation as yet. If the ions moved through solutions a t the same rate as through pure water there should be no such change; it is commonly ignored in calculations, hut is still one of the unsolved problems of physical chemistry. A possible cause of the change is that one ion combines with more water than the other, thus increasing its size and decreasing its velocity. There is definite proof that the ions are combined with considerable water and it is reasonable to suppose that the extent of this solvation changes with the proportion of water available, and with the tempera.ture.” On p. 369, under colloids, the author says that “viscous emulsions and gels have the same structure; a stiff jelly is often convertible into an emulsion by heating, and it returns again to the state of jelly after cooling. In each case microscopic droplets of one liquid phase are completely surrounded hy a continuous film of the other liquid phase. It is not necessary that the cont.inuous phase be present in greater quantity than the dispersed phase; a cross-section of an emulsion in which the disperse phase is present in excess might look something like a section through a cake of honey, with thin films of continuous phase (represented by the wax cell walls) surrounding droplets of dispersed phase.” The reviewer would be quite satisfied if he could prove which jellies had a honeycomb W i l d e r D. Bancrojt structure.
A Dictionary of Chemical Solubilities. Inorganic. By A . M . Comey and Dorothy A . Hahn. Second edition. 22 X 15 cm; p p . xviii 1141. New York: The Macmillan Company, 1921. Price: $~q.oo.--U’hen the first edition appeared It is the reviewer criticized it (1, 53) as typical of everything that was bad. a pleasure to note that the second edition is a distinct improvement in many respects. Limits of solubility are now given in many cases and attention is paid very often to the nature of the phase which crystallizes. There has not been any complete revision in regard to these points. On p. 144, €or instance, we read that anhydrous calcium chloride is soluble in 1.58 parts of water a t 10.2’. Everybody knows that this is not so and everybody knows that what Kremers found was that the solution saturated with respect t d CaC12.6H20 contains one part of anhydrous calcium chloride to 1.58 parts of water. The editors have not
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distinguished between the perfectly proper method of stating the analytical data and the absolutely improper method of stating the solubility. In this particular case there is no harm done because everybody recognizes the error; but it rather leaves one up in the air as regards less familiar substances. While on this point the reviewer protests against the statement that anhydrous calcium chloride is very soluble in water with evolution of heat. The formation of hydrated calcium chloride is accompanied by an evolution of heat but both anhydrous and hydrated calcium chloride are more soluble with rising temperature and therefore dissolve with absorption of heat. Because people speak of iron dis5olving in sulphuric acid, statements of this sort are included even in the second edition, though of course no solubility can be given. The weird alphabetical arrangement is continued. The reviewer thinks that there are probably data on hydrobromic acid somewhere in the book; but he could not find them. The book is valuable on account of the immense amount of data in it; but the size has doubled and the cost has nearly trebled. Under the circumstances it would have been better if the editors had cut out a great deal of the dead wood and had presented the data in the best possible way. It is hard to believe that it would have taken more work to have revised the book well than to have revised it badly. The publishers should have insisted on the work being done properly. While the volume will be a necessity in every library, the wildest flight of imaginaWilder D . Bancroft tion cannot make it a credit to American chemistry.
Handbuch der Mineralchemie. By C. Doelter. Vol. 3 , Part 6. 26 X 19 cm; p p . 164. Dresden: Theodor Steinkopf, 1918. Price 78 cts.-This number contains native bismuth and the oxides of bismuth, vanadium, the uraniumvanadium and the vanadium-silica minerals, and water. The reviewer was interested in the statement, p. 816, that the crystallized oxide of bismuth has a pearly to adamantine lustre. Some sort of real classification of lustres should be made and if neither the physicist nor the mineralogist will do it, it is apparently a problem for the physical chemist and the psychologist. The fact that carnotite occurs in this number will make it of interest to many people. Sixty pages are given up to a discussion of water, which a t first sight seems out of place. No special justification is offered for including it, except that water occurs commonly on the earth. If one waives the question of appropriateness, it is certainly a good thing to have accessible the compilation of data which Kremann has presented. He gives the data for: the equilibrium constant; the electrolysis; the electrolytic dissociation; water as solvent; hydroylsis; hydrogen peroxide; catalytic action; phase diagram ; vapor pressure curve; boilingpoint; rate of vaporization; heat of vaporization; heat of fusion; melting point curve for ice; varieties of ice; volume relations; specific heat; viscosity; index of refraction; electrical double refraction; surface tension; molecular constitution; and water of crystallization. The remaining twenty-five pages are given Wilder D . Bancroft up to a discussion of natural waters.
