I70 



NATURE 



{Dec. 26, 1878 



and enabled chemists to introduce something like a 

 system by which analogous phenomena could be classi- 

 fied and referred to a common cause ; further, how the 

 experiments of Black, Cavendish, and Lavoisier first 

 showed the importance of attending, in the study of 

 chemical changes, to the alteration in weight of the 

 substances concerned ; and how Lavoisier was ultimately 

 led to the true theory of chemical combination, which 

 regards it as consisting simply in the addition of one 

 element to another, the weight of the product being 

 exactly equal to the sum of the weights of the combining 

 bodies. 



Next follows a sketch of the labours of Bergmann, 

 Richter, Cavendish, and others, which led up to the 

 establishment by Dalton of the great doctrine of com- 

 bination in multiple proportions, on which he founded 

 the "atomic theory." The early experiments of Dalton 

 are briefly described ; his table of the relative weights of 

 the atoms of certain elementary and compound bodies is 

 given ; and the Introduction ends with an account of the 

 manner in which the exact values of the atomic weights 

 were determined by Thomas Thomson, WoUaston, and 

 more especially by Berzelius ; of the discovery of the 

 compound nature of the alkalis by Davy, and of a num- 

 ber of new elements by various chemists ; and lastly, of 

 the development of Organic Chemistry and its true 

 relations to the chemistry of inorganic bodies ; and 

 the final establishment — chiefly by the researches of 

 Liebig — of the fact that the science of Physiology con- 

 sists simply in the physics and chemistry of the living 

 body. 



The Historical Introduction is followed by a chapter 

 on the General Principles of Chemical Science, in which 

 the methods by which the laws of chemical combination 

 have been established are more fully described, especially 

 that by which Lavoisier demonstrated the nature of com- 

 bustion and the indestructibility of matter. This part of 

 the subject is well illustrated by diagrams of the appa- 

 ratus used in these important investigations. A list of 

 the elements with their combining weights is then given, 

 and a table exhibiting the arrangement of the elements 

 in groups, chiefly, but not entirely, according to their com- 

 bining capacity or quantivalence. Next follows a sec- 

 tion on the laws of chemical combination, the me- 

 thods of analysis and synthesis, the manner in which 

 the law of equivalents and the law of multiple 

 proportions were established, and the explanation 

 of these laws by Dalton's atomic theory. This theory 

 is adopted by the authors as the basis of all their 

 explanations of chemical phenomena, and in this we think 

 tiey are right : for without insisting on this theory as a 

 matter of absolute certainty, we cannot but regard it as 

 the only theory yet proposed which gives any rational and 

 connected view of the laws of chemical action as estab- 

 lished by experiment. There are, indeed, chemists of 

 great eminence, who do not admit it, but hold out 

 expectations of much more satisfactory explanations 

 founded on dynamical views of chemical action. But 

 these views have not yet been sufficiently developed to 

 f jrm a connected theory, and meanwhile we must make 

 what we can of the theory of atoms, which, after all, is 

 not necessarily inconsistent with any dynamical laws, or 

 in other words, with any relations of matter to heat and 



electricity, that future experiment and observation may 

 develop. There are, indeed, some philosophers who 

 would have us believe in motion without matter, or in 

 other words, in the movement of nothing at all ; but 

 this is high transcendental ground, on which we must 

 humbly confess our inability to tread. 



The consideration of the volume-relations of gases in 

 combination, as established by Gay-Lussac, leads to the 

 statement of Avogadro's law, according to which equal 

 vobimes of all gases contain the same number of molecules. 

 This the authors rightly put forward as a hypothesis, the 

 truth of which— like that of the law of gravitation — must 

 be established by its accordance with the whole range of 

 observed phenomena : for as such it must be received by 

 the ordinary student, who is scarcely prepared to under- 

 stand the manner in which it may be shown to follow as 

 a necessary consequence of the kinetic theory of gases. 

 An exposition is then given of the physical properties of 

 gases, the continuity of the liquid and gaseous states, as 

 demonstrated by Andrews, also a sketch of the kinetic 

 theory of gases; and the chapter concludes with an 

 explanation of the principles of Chemical Nomenclature 

 and Notation. 



The remainder of vol. i. treats of the Non-metallic 

 elements. The preparation and properties of these bodies 

 and of their compounds with one another, together with 

 their industrial applications, are carefully described, and 

 excellent figures are given of the apparatus employed for 

 investigation and lecture illustration, also of manufactur- 

 ing "plant." Especially worthy of notice are the illus- 

 trations connected with the manufacture of bleaching 

 powder, sulphuric acid, and coal-gas. The volume con- 

 cludes with a chapter on Crystallography, copiously illus- 

 trated with diagrams. The notation used is that of Nau- 

 mann, which, for descriptive purposes, is perhaps the 

 clearest and most graphic yet devised. 



Vol. ii., part i is devoted to the general properties and 

 classification of the Metals, and to the special description 

 of those belonging to seven out of the twelve groups in 

 which they are arranged by the authors. In this part of 

 the work we find the same clearness and accuracy of 

 description and explanation which are conspicuous in 

 the first volume, both in the purely scientific portions 

 and in those w^hich relate to industrial applications. 

 Excellent descriptions and figures are given of the manu- 

 facture of alkali and of glass, and of the metallurgy of 

 zinc, copper, lead, silver, and mercury. 



The book is well printed, and remarkably free from 

 typographical errors. The few that we have noticed are 

 not likely to mislead, and it is therefore not worth while 

 to specify them, with the exception, perhaps, of one, 

 occurring on p. 38 of vol. i., where it is said that the 

 specific heats of the several elements are "universally" 

 (instead of "inversely") proportional to their atomic 

 weights. 



The work, when finished, will afford the most complete 

 systematic exposition of the existing state of chemical 

 science that has yet appeared in the English language ; 

 and chemists will look forward with pleasure to the ap- 

 pearance of the second part of vol. ii., which will con- 

 tain a description of the Iron manufacture, and to that 

 of vol. iii., which will be devoted to the ever-growing 

 subject of Organic Chemistry. 



