390 Scientific Intelligence. 



to the best results. The book cannot fail to be of excellent 

 service for the class of Junior students for whom it was prepared, 

 and so is a valuable contribution to the teaching of physics from 

 the admirable Ryerson laboratory. g. r. b. 



8. Text-book of 'Physical Chemistry ; by Clarence L. Speyers, 

 Rutgers College. 8vo, pp. viii, 224. New York, 1897. (D. Van 

 Nostrand Co.)— Physical chemistry is here defined as " the sci- 

 ence which has for its object the investigation of chemical changes 

 by physical methods." In his preface the author says : " I have 

 adopted the view that matter is a collection of energies in space, 

 considering the relations of the energies to be the prime object of 

 investigation. With Ostwald, I feel confident that the material- 

 istic interpretation has passed its prime and has no promise for 

 the future." " The different forms of matter," he says, " we may 

 define as different collections of activities in space, the quality and 

 quantity of these activities changing with the different forms of 

 matter." And again : " We need energy and a something to 

 enable energy to collect in space before we get a material sub- 

 stance. This something which enables and perhaps causes the 

 energy to collect in space we shall call matter." So that it would 

 appear that matter has two definitions: first "a collection of 

 energies," and second, a " something," an unknown entity which 

 causes these energies thus to collect ; the latter being not very 

 unlike our present conception. Moreover " the belief that oxygen 

 and hydrogen still persist as such in water, and in general the 

 idea that the elements persist in a compound," is not justifiable. 

 " All we may assume is that the conditions that cause the break- 

 ing up of a collection require the formation of those collections 

 which went to make up the collection j ast destroyed. But to claim 

 that these collections originally existed in the collection that 

 broke up, is entirely opposed to the evidence of our senses." It 

 will be seen from these quotations that the author follows Ost- 

 wald pretty closely even when he is most radical; sometimes even 

 surpassing him. Thus he uses time, space and energy as his 

 fundamental units ; but he denounces the kinetic theory of gases 

 as "a troublesome thing " which "is becoming an object of ridi- 

 cule." Nevertheless the book will serve a useful purpose. It 

 contains in compact form excellent chapters on energy, £ases, 

 heat, physical changes, equilibrium, chemical kinetics, phases, 

 variable temperature, electrochemistry and ions. The problems 

 are a valuable addition to the text. g. f. b. 



9. The Tutorial Chemistry. Part II. Metals; by G. H. 

 Bailey, Ph.D. Edited by William Briggs, M.A. 12mo. pp. viii, 

 300. London, 1898 (W. B. Clive).— This little book treats of the 

 metallic elements in much the ordinary way, except that a more 

 considerable space is given to chemical physics than is usual in 

 manuals of this grade. The grouping follows the order of the 

 periodic system and in an appendix is given a chapter on crystal- 

 lography, one on spectrum analysis and a third on a series of use- 

 ful experiments. The book will prove of value, we think, for 

 second year students. 



