Chemistry and Physics. 525 



properties are discussed and references given to the original 

 investigations. The third part deals with the microscopy of 

 metals; directions are given for grinding, polishing and etching 

 the sections, the construction and use of the Martens and 

 Le Chatelier microscopes are described, and several pages are 

 devoted to the technique of photograph} 7 . In the fourth part 

 the special metallography of the iron-carbon alloys is considered. 

 As a whole, the book seems to be admirably adapted to serve as 

 an introduction to this comparatively new subject whose techni- 

 cal importance is already widely recognized. h. a. b. 



10. Lehrbuok der theoretisehen JSlekirochemie anf thermody- 

 namischer Q-rundlage ; by J. J. van Laar. Pp. xii + 307. Leip- 

 zig, 1907 (Wilhelm Engelmann), Amsterdam (S. L. van Looy). — 

 Although this is not the first book on electrochemistry to give a 

 systematic treatment of the subject from the standpoint of the 

 theory of the thermodynamic potential, it is in many respects the 

 most satisfactory one that has yet appeared. By omitting all 

 description of experimental processes, and by judicious limitation 

 of the amount of numerical data employed for purposes of illus- 

 tration, the author has been able, within the compass of 300 pages 

 of large print, to cover a fairly wide field with more than the 

 usual thoroughness. The book is up to date both in spirit and in 

 subject matter, and the style clear and direct. As would natu- 

 rally be expected in a treatise of this sort, the thermodynamic 

 potential is used to the complete exclusion of the osmotic pressure 

 in the derivation of the formulas for the electromotive force of 

 galvanic cells. 



Among the noteworthy features of the volume are the critical 

 summary of the most trustworthy values for the velocities of the 

 commoner ions (p. 31), the comprehensive review of work on 

 conductivity in non-aqueous solvents (chap, iv), and the clear 

 and satisfactory discussion of oxidation cells and gas cells (chap, 

 ix) and of the relation between potential and surface tension of 

 mercury electrodes (chap. xii). 



The work is hardly suitable for the use of beginners as an ele- 

 mentary text-book, but will recommend itself to those of wider 

 experience, as it contains much that is interesting and suggestive. 



E. V. N". 



11. Comparative Electro-Physiology • by Jagadis Chundee 

 Bose. Pp. xliii, 760 with 406 figures. London, 1907 (Longmans, 

 Green & Company). — This is a somewhat unique attempt to 

 point out a continuity between the most complex living and the 

 simplest inorganic matter — to interpret all responsive phenomena 

 on a uniform basis. "In this demonstration of continuity it has 

 been found that the dividing frontiers between physics, physiol- 

 ogy, and psychology have disappeared." " All the responsive 

 phenomena of the animal are thus found to be foreshadowed in 

 the plant, and this to such a degree that in the common script 

 of the response record the one is indistinguishable from the 

 other .... Both alike are responsive, and similarly responsive, to 



Am. Jour. Sci.— Fourth Series, Vol. XXV, No. 150.— June, 1908. 

 35 



