350 Messrs. Schlossberger and Kemp on the Proportion of 



observed facts go to prove that platinum reduces the gases to 

 a state analogous to the nascent state, i. e. one at which their 

 specific chemical energies are at the highest, but it does not 

 change their specific energies; thus platinum enables gaseous 

 oxygen to combine with gaseous hydrogen, but it does not 

 give to oxygen the affinities of chlorine, or to hydrogen those 

 of potassium. Even the granting this hypothesis, however, 

 does not extricate us, as whatever specific power the platinum 

 may possess in respect to the gas, it must also possess in re- 

 spect to the electrolyte ; it can scarcely be supposed to assist 

 combination and yet not to prevent decomposition of the same 

 molecule; it is an equation upon any view. 



Nor can it be supposed that the action in the liquid of the 

 gas battery cells differs from other cases of electrolysis; the 

 line of discharge in the gas battery affects the magnet, and in- 

 deed forming portion of the voltaic circuit, it would be con- 

 trary to all analogy to suppose it exceptional in respect of its 

 mode of action. An hypothesis might be framed which would 

 regard the action of the gas battery as resulting from the 

 formation of a soluble peroxide of hydrogen and perhydruret 

 of oxygen; but if so, a similar hypothesis must be extended to 

 all cases of electrolysis ; and this view presents many difficul- 

 ties. Perhaps some of your correspondents may be able to 

 solve the theorem ; for if not reconciled with facts, however 

 ingenious and useful the theory of Grotthus be, it is a theory, 

 while the gas battery is a fact, and in case of collision, it is 

 needless to say which must go to the wall. 



I remain, my dear Sir, 



Yours very truly, 



W. R. Grove. 



LTII. 071 the Proportion of Nitrogen contained in Alimentary 

 Substances taken from both the Organic Kingdoms as a com- 

 parative measure of their Nutritive Po'xser. By Dr. J. 

 Schlossberger and Alexander Kemp, Assistant Chemi- 

 cal Teachers in the University of Edinburgh^. 



'T^HE distinction between the elements of the reproductive 

 '* and those of the respiratory functions, is probably one 

 of the most fertile ideas for which physiology is indebted to 

 modern chemistry; even if we do not admit that division in its 

 full extent, nevertheless we must allow it to be a beautifully 

 conceived idea, and one founded on a great amount of observa- 

 tion. It may be assumed with safety that no other classifica- 

 tion of the substances comprised under the vague designation 



* Communicated by the Authors. 



