670 



SCIENCE. 



[N. S. Vol. II. No. 46. 



out the diseases which have been caused by 

 these visits." 



Pages 30-34 are taken up with notes on the 

 Tinneh tribe of Nicola Valley, now extinct, 

 whose language Dr. Boas shows ' ' was much 

 more closely related to the Tinneh languages 

 of British Columbia than to those farther south, 

 although it would seem to have difl'ered from 

 the former also considerably. ' ' A noteworthy 

 addition to our knowledge of British Columbian 

 peoples is the sketch of the Ts'ets'a'ut, first 

 scientifically studied by Dr. Boas ( pp. 34-48 ) 

 and of the Nisk4 (pp. 49-62), details of whose 

 sociology and folk-lore, etc., are given. The 

 linguistics of the report (pp. 62-71), though 

 not extensive, are new and valuable. Taken 

 all together this excellent report fitly crowns 

 the work of the committee under whose aus- 

 pices these investigations were inaugurated. 

 It is sincerely to be hoped that some way will 

 be found to continue researches that have been 

 productive of such great results and added so 

 much to American anthropology and linguis- 

 tics. Alex. F. Chamberlain. 



Solution and Electrolysis. By W. C. D. Wet- 

 HAM, M. A. Macmillan & Co., London and 

 New York. Price $1.90. 

 This book forms one of the physical series of 

 the Cambridge Natural Science Manuals. It 

 gives a summary of the work which has been 

 done up to the present time, but particularly 

 during the last twenty years, on the physical 

 properties of solutions. This subject forms a 

 branch of physical chemistry which has, within 

 the last few years, attracted towards it a num- 

 ber of eminent investigators, who have obtained 

 results of great interest and importance. To 

 the student of the properties of matter it is dif- 

 ficult to conceive of any more fascinating branch 

 of study than that of diffusion, osmotic pressure, 

 the influence of dissolved substances on the 

 freezing point, boiling point and vapor pressure 

 of solvents, and the very curious difference be- 

 tween electrolytic and non-electrolytic solutions. 

 The subject is only beginning to crystallize and 

 few systematic treatises, and these mostly Ger- 

 man, are devoted to it. The present work will 

 therefore be welcomed by readers who prefer 

 works written in the English language. It gives 



in brief form an account of the results so far 

 arrived at and the theories towards which they 

 point. This summary will no doubt prove of 

 great service to students and also to physicists 

 and chemists who have not followed the inves- 

 tigations in the publications of scientific socie- 

 ties and the journals. 



The treatment of the subject is perhaps rather 

 too brief, but outside of that the presentation 

 of the subject is good and the printing is, as 

 usual, very satisfactory. A few instances of 

 somewhat careless statement exist as, for in- 

 stance, the statement of the thermodynamic 

 cycle on p. 26, which is incomplete. This is 

 unfortunate, because everything with regard to 

 the second law of thermodynamics seems to 

 be a source of difficulty to students. Again, 

 the references are occasionally misleading. 

 Take, for example, that to Jahn's work on the 

 Peltier effect given on p. 117. Most students 

 would interpret it to mean that the idea of test- 

 ing contact difference of potential through Pel- 

 tier's effect originated with Jahn, whereas it 

 has been in the minds of physicists and has given 

 rise to discussion for forty years or more. 



The paragraph on p. 204 on the explanation 

 of the possible effect of specific inductive 

 capacity on ionization power seems unsatisfac- 

 tory. To any one who requires an explanation 

 that given is probably useless. 



Fitzpatrick's tables on the ' electro-chemical 

 properties of solutions, ' originally printed in the 

 British Association proceedings, are given in an 

 appendix and will no doubt be welcomed by 

 many. 



The book is well worth perusal and is a valu- 

 able addition to our works on physics and 

 chemistry. Thomas Gray. 



Critical Periods in the History of the Earth. By 

 Joseph Lb Conte. Bulletin Dept. Geology, 

 Univer-sity of California. Vol. I., No. 11, 

 pp. 313-336. Berkeley, August, 1895. (Re- 

 printed.) 



This is, in a somewhat condensed form, the 

 address which opened the discussion, by the 

 Congress of Geologists at Chicago, August, 1893, 

 on the question ' 'Are there any natural divisions 

 of the geological record which are of world-wide 

 extent? " The author begins with a brief refer- 



