932 



SCIENCE. 



[N. S. Vol. VIII. No. 209. 



ment on this fundamental change of our 

 conceptions, yet it is a fact that the most 

 ■widely different properties of solutions 

 agree qualitatively with the new concep- 

 tions. Quantitatively, the result calculated 

 agrees very nearly with that found, but, 

 thus far, the agreement is not always per- 

 fectly satisfacto^J^ It is of chief impor- 

 tance for our purpose that a new impulse 

 was thus given to the study of solutions of 

 salts, acids and bases, i. e., chieflj' to inor- 

 ganic compounds. 



A final remark in closing : "While it has 

 been repeatedly emphasized, in the foregoing 

 that it is chiefly inorganic chemistry that 

 has been advanced by the new theoretical 

 considerations, yet it is not meant that or- 

 ganic chemistry has thus lost in interest. 

 On the contrary, the science of chemical 

 equilibrium can be applied also here, and 

 has already been thus applied. 



The action of ferments is then taken up, 

 and the work of Tammann and others 

 cited to show that such act, at least in 

 some cases, to only a limited extent, a con- 

 dition of equilibrium being reached before 

 the decomposition is complete. Thus, 

 amygdalin is only partly broken down by 

 emulsin, and the breaking-down goes far- 

 ther if the decomposition products are re- 

 moved. If, on the contrarj', he had added 

 the decomposition-products he would, per- 

 haps, have effected the synthesis of amyg- 

 dalin. In case the ferment is not changed 

 by its action, on theoretical grounds a con- 

 dition of equilibrium must be introduced, 

 and not a total transformation, and, there- 

 fore, the opposite reaction should be realized. 

 It is a fair question to ask whether (from 

 the science of equilibrium) sugar cannot 

 be formed from carbon dioxide and alcohol, 

 under the influence of zymase, when the 

 pressure of the carbon dioxide exceeds a 

 certain limit ; and also whether trypsin is 

 not in the position, under conditions given 

 by the science of equilibrium, to form albu- 



min from the decomposition products which 

 it itself yields ? 



" If I have gone too far in these last ex- 

 pressions they may remain as proof that I 

 always have a warm heart for organic chem- 

 istry. " Van't Hofif concluded with the 

 wish that Germany, which is in danger of 

 being surpassed in inorganic chemistry by 

 other nations ; which has recently lost from 

 this field such men as Victor Meyer, Lo- 

 thar Meyer, Gerhard Kriiss and Clemens 

 Zimmermann, will soon again occupy a 

 leading position, thi'ough the choice of 

 j-oung men of our science to enter this 

 field. 



Harky C. Jones. 

 Chemical Laboratory, 



Johns Hopkins University, 

 November, 1898. 



THE TAILLESS BATBACHUNS OF EUROPE.* 

 The anurous salient amphibians, or tail- 

 less batrachians, have been long favorite 

 subjects of study in Europe, and much has 

 been written upon their habits. Only a 

 few years ago (in 1890) Dr. J. de Bedriaga 

 published an elaborate monograph of the 

 Amphibians of Europe (Die Lurchfauna 

 Europas) giving very full descriptions of 

 the species and their manner and customs. 

 Now we have completed a still more elabo- 

 rate work on a single order of Amphibians 

 — the Salientia — including the frogs and 

 toads and their relations. This work, en- 

 titled ' The Tailless Batrachians of Europe,' 

 is by Mr. G. A. Boulenger, and has been 

 'issued to the subscribers to the Ray Society,' 

 in two bound volumes or parts for the years 

 1896 and 1897; the pagination is continuous 

 from the first into the second volume (pp. 

 211-376). Doubtless many of the ' sub- 

 scribers ' will rejoice in the diversifieati&n 

 of the subjects monographed, for nearly a 



* The Tailless Batrachians of Europe. By G. A. 

 Boulenger, F.K.S. London : printed for the Ray So- 

 ciety. 1897-1898. 2 parts, 8vo., t. p., iii, 376 pp., 

 24 pi., 7 maps. 



