68 Dr. Partes on the Elimination of Nitrogen. [June 20^ 



conceive tlie opinion itself was probably correct. Because even if the 

 work is done during the period when nitrogen is added, and not when it 

 is eliminated, it is difficult to suppose that the changes in the nitrogen 

 are on a scale large enough to account for the result, or that the trans- 

 formation of a particle of blood-albumen into a particle of muscle-albumen 

 could be attended by any chemical changes which per se could equal the 

 mechanical force produced. But we can imagine that such a transforma- 

 tion may be the cause of changes in the non-nitrogenous substances to 

 which the manifestation of force is really owing. There is no reason 

 why disintegration should be more attended with such changes than 

 formation. Indeed it is perhaps more often that the union of chemical 

 substances is attended by signs of transformation of force than their dis- 

 union. Or the stimulus which causes the addition of the nitrogen to the 

 muscle may at the same moment originate the changes in the non-nitro- 

 genous substances. 



The fact that the substances the presence of which in the muscle 

 suspends the contraction (and therefore, if I am right, the growth of 

 muscle), appear from E;anke's latest observations to be derived from the 

 non-nitrogenous substances, is another argument in favour of the view 

 that great changes go on in these substances during muscular action. 



If the opinion of Professors Pick and Wislicenus to this extent, and 

 if the experiments of E,anke and others on the effect of the effete pro- 

 ducts be adopted, the following would be the theory of muscular action 

 I would propose. 



"When a voluntary muscle is brought into action by the influence of 

 the win, it appropriates nitrogen and grows ; the stimulus or the act of 

 union gives rise to changes in the non-nitrogenous substances surround- 

 ing the ultimate elements of the muscular substance which cause the 

 conversion of heat into motion. The contraction continues (the will 

 still acting) until the effete products of these changes arrest it ; a state of 

 rest ensues, during which time the effete products are removed, the muscle 

 loses nitrogen, and can again be called into action by its stimulus. 



This theory not only explains the experiments now recorded, but 

 simplifies our ideas both of the growth and of the wasting of muscle, 

 and seems likely to explain more easily some processes in disease. 



It is also in greater accordance with the rules of diet derived from 

 experience than the theory of Pick and Wislicenus. If correct, it shows 

 why the muscle requires nitrogen for its action, and why increased 

 action requires increased nitrogen. The food must either supply this, 

 or the store of nitrogen in the blood and other organs must be lessened*. 



^ That an increased supply of fat, and perhaps of starches, is also desirable has long 

 been practically recognized, though the store of fat already in the body renders this less 

 necessary for a time. The observations of Lawes and Gilbert seem to me to render it 

 possible that when a muscle parts with its nitrogen, fat is formed, and if so, a muscle 

 disintegrating during rest may form a store of fat in its texture which may be further 

 transformed at the next addition of nitrogen, i.e. at the next contraction. 



