﻿CI KREXT LITERATURE 



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occupied by 2 to 4 different species are plotted. These things, together with 

 Fuller. 



The plant is made in the main of colloids. Notwithstanding this fact, 

 until recently, so far as we have tried to explain its activity on the chemical 

 basis at all, it has been largely in accordance with laws of homogeneous systems. 

 Lately we are coming to realize that the laws of colloids are of first importance 

 in answering many questions concerning the plant, its environment, and the 

 interrelation of the two. 



With the translation of the first half of Ostwald's Grundriss dcr Kolloid- 

 chemie we have an excellent statement of a portion of the principles of the 

 subject available in English. Ostwald was turned into colloid chemistry 

 by certain problems met in biology, and the translator is an animal physiolo- 

 gist dealing with very fundamental problems in the colloidal side of his subject. 

 These facts should especially interest biologists in the book. It is to be 

 regretted that the second half has not yet appeared in German, and is therefore 

 not available for translation; but one sees the rapidity of the growth in colloid 

 chemistry when he recognizes that the first half passed through three editions 

 without opportunity for writing the second half. 



Ostwald, with his attractive way of presenting a subject, hardly needs an 

 introduction to an American scientific audience, following his recent extensive 

 lecture tour in this country. The translator says "Wolfgang Ostwald's 

 writings represent in colloid chemistry what those of Charles Gerhardt 

 represent in organic, Justus Liebig in agricultural, and Wilhelm Ostwald in 

 physical chemistry." Notwithstanding the fact that many phases of the sub- 

 ject of greatest interest to physiologists are still to be treated in the second half, 

 the volume is a much-needed reference book for plant workers. 



Taylor's 3 book upon colloids is a far less exhaustive statement, but offers 

 a good general outline of the subject. Part I (163 pp.) deals with general 

 properties of colloids; part II (56 pp.), with methods of preparation; part III 

 (42 pp.), with surface phenomena or adsorption; and part IV (56 pp.), with 

 applications of colloid chemistry (semi-colloids, dyeing, tanning, soil, purifica- 

 tion of sewage, and applications to biology). Those interested only in the 

 general principles of the subject will find this little hook most satisfactory. 



lated from 3d Ger. ed. by Martin H. Fischer, with the assistance of K. K. Oespf.r 

 and L. Berman. 8vo. pp. xii+278. Philadelphia: P. Blakiston's Son & Co. 1915. 



