346 Messrs. Cross and Bevan on the Correlation of 



battery-current the sensitiveness would be improved. Or, if 

 we suppose the circumferential linear speed of the disk rather 

 than its angular speed to be constant, the sensitiveness would 

 be unchanged. If the larger coil were made of the same kind 

 of wire as the smaller, its resistance would be augmented; but 

 if the dimensions of the section were also doubled, so as to 

 keep the proportions throughout, the advantage in this respect 

 would lie with the larger apparatus. 



On the whole, I am of opinion that if it is desirable at the 

 present time to construct apparatus on the most favourable 

 scale, so as to reach the highest attainable accuracy, the modi- 

 fication of Lorentz's method last described is the one which 

 offers the best prospect of success. Before this is done, how- 

 ever, it appears to me important that the value now three 

 times obtained in the Cavendish Laboratory by distinct me- 

 thods should be approximately verified (or disproved) by other 

 physicists. To distinguish between this value and those ob- 

 tained, for instance, by Kohlrausch, by Lorentz, or by the 

 first B.A. Committee, should not require the construction of 

 unusually costly apparatus. Until the larger question is dis- 

 posed of, it appears premature to discuss the details of arrange- 

 ments from which the highest degree of precision is to be 

 expected. 



XXXIX. On the Correlation of the Chemistry of the Carbon 

 Compounds icith the Phenomena of Life. By C. F. Cross 

 and E. J. Beyan*. 



IT is not for us to dilate upon the marvellous progress of 

 Organic Chemistry during this century, nor to find fault 

 with the inevitably specializing tendency of research in the 

 province of the carbon compounds ; and we certainly owe an 

 apology fur entering upon a subject of such magnitude as the 

 correlations of chemical with biological science. That which 

 we offer is derived not so much from the consciousness of being 

 able to originate views of these correlations which shall be more 

 productive than certain which appear to prevail, as from the 

 practical necessities of the investigations in which we find 

 ourselves engaged, the paucity of the landmarks to which 

 Ave have to look for guidance, and the misleading character 

 of certain of the recognized principles and methods which lias 

 become manifest in the results of their application. In fine, 

 there are numerous points in that portion of Biochemical 

 Science the study of which we are prosecuting which call 

 for critical discussion; and the existence of the imperfections 

 * Communicated by the Authors. 



