June 8, 1900.] 



scmNCJj. 



905 



ing of the principles of the science on the ordi- 

 nary work of the chemist. The subjects dis- 

 cussed in the booli are accordingly selected with 

 this aim in view. Thus by far the larger part 

 of the work is devoted to the consideration of the 

 principles of physical and chemical equilibrium 

 and their applications, and to a discussion of the 

 theory of electrolytic dissociation and the expla- 

 nations which it offers of the physical and chem- 

 ical properties of salt solutions, while scarcely 

 ninety pages are occupied by the description of 

 the methods of atomic and molecular weight 

 determinations and by the treatment of the 

 theoretical conclusions derived therefrom in re- 

 gard to valence, structure, and the relation of 

 properties to atomic weight and to constitution. 

 This is entirely rational from the point of view 

 of the author ; for though atomic and molec- 

 ular weight determinations have great signifi- 

 cance historically and theoretically from the 

 fact that upon them is founded the structure 

 theory of organic chemistry, in its comprehen- 

 siveness by far the most important theory that 

 physical science has yet developed, it is never- 

 theless true that this theory is now employed 

 without much reference to the physical rela- 

 tions on which it was originally based, so that 

 a knowledge of the latter is not of great value 

 from a practical standpoint. On the other 

 hand, the electrolytic dissociation theory and 

 the laws relating to equilibrium and reaction- 

 velocity find constant application to the daily 

 work of the industrial, the analytical, and the 

 synthetic chemist. 



It is scarcely justifiable to criticise the work 

 adversely on account of the lack of system and 

 logical sequence which it undeniably exhibits, 

 for it is distinctly not intended as a complete, 

 precise, and consistent presentation of the sci- 

 ence of general chemistry, but rather as a direct 

 accompaniment of a concrete and highly prac- 

 tical character to the instruction ordinarily 

 given in other branches of chemistry. It is a 

 book which is especially suitable for use in con- 

 nection v/ith the brief courses on theoretical 

 chemistry which should be given to undergrad- 

 uate college students. It is also admirably 

 adapted to the needs of the teachers of elemen- 

 tary chemistry and of workers in allied sciences 

 or in industrial chemistry who desire to acquire 



readily a knowledge of the more concrete and 

 practical side of the subject. It is, never- 

 theless, the opinion of the reviewer that every 

 thoroughly trained chemist, whether educated 

 at a university or technological institute, should 

 receive a more systematic, logical, precise, and 

 thorough course in theoretical chemistry than 

 that which the present work is intended to give, 

 primarily in order that he may acquire the 

 power of close and accurate thinking, in which 

 students of chemistry are, unfortunately, as a 

 rule, seriously deficient and inferior to students 

 of physics, and secondarily that he may add to 

 his store of specific chemical information a 

 thorough knowledge of the underlying and re- 

 lated general principles — a kind of knowledge 

 which cannot fail to be of great practical value 

 to him, whether he engages in teaching or in- 

 dustrial pursuits. It is, however, unfortunately 

 true that, with the possible exception of the re- 

 cent work of Nernst, which has not yet been 

 translated and which is too difficult of compre- 

 hension except for advanced students, there is 

 no satisfactory text-book to accompany a course 

 of the latter character. 



The manner in which the task of the author 

 has been executed is highly satisfactory. The 

 work is written in a readable and unwearying 

 style. The principles are clearly stated, and 

 are always illustrated by concrete examples. 

 The errors to which beginners are liable are 

 especially pointed out. The treatment is a de- 

 scriptive, not a mathematical one ; but the au- 

 thor has not hesitated to employ mathematical 

 expressions where greater clearness is thereby 

 attained. The author, who has supplemented 

 his university instruction in physical chemistry 

 by more than ten years' experience in teaching 

 and research, shows himself throughout the 

 book to be a thorough master of his subject, to 

 have a sound appreciation of the relative im- 

 portance of the various principles and theoriesj 

 and to be entirely free from one-sidedness and 

 the desire for radical innovations. 



The work is therefore of such a character as 

 to justify the hope that it will mark the begin- 

 ning of a new epoch in the teaching of general 

 chemistry in this country and in England. 



Arthur A. Noybs. 



Massachusetts Institute of Technology. 



