IN MUSCULAR ACTION. 



composition of the albuminous and of the crystallizable, 

 saccharine, and fatty elements which occur in muscles. At the 

 same time there is some diminution of the total albuminates, of 

 the watery extracts and of the substances from which lactic, 

 carbonic, and the fatty acids are formed (J. Ranke). It is 

 impossible to go more accurately into the compounds actually 

 found in the living muscle, for of kreatin, grape-sugar, inosite, 

 sarkiri, myosin, &c., some are probably, and the last certainly, 

 not formed till after death, and most of the experiments are 

 vitiated by the fact that death takes place during them (L. Her- 

 mann). However, in the living state the reaction certainly 

 becomes acid, and there are found products which lessen the 

 capacity of the muscle for work and are called fatigue-stuffs. 

 These are supposed to be chiefly lactic acid, carbonic acid, and 

 phosphate of potash. That the fatigue-stuffs have this effect is 

 shown by the fact that if they are washed out with a weak 

 solution of common salt, and if oxygen be then furnished, the 

 activity of the muscle is restored : likewise, if lactic acid or 

 flesh-extracts be injected into a fresh muscle, the same weak- 

 ness is produced. Recovery from fatigue therefore depends on 

 the restoration of oxygenated blood and the neutralization of 

 these fatigue-stuffs and their final absorption by the capillaries, 

 the plastids of which decompose them into blood and effete 

 products. During the active state force is evolved and con- 

 sumed in mechanical work, the electric muscle current dimin- 

 ishes almost to zero and heat is also produced. 



The vital and chemical processes during rest and motion are 

 thus not essentially different, but form merely a plus and minus 

 of the same state. In fact the so-called state of rest is always, 

 (in health) a state of minimum of contraction, as is seen by the 

 drawing towards the opposite side, when the nerves of one side 

 are cut or paralyzed. The so-called tonicity is nothing but 

 partial contraction. 



Now, although it is certain that the total force for muscular 

 work is derived from the passing down of complex compounds 

 to a simpler state of combination with satisfaction of stronger 

 affinities,* and ultimately may be described and measured as 



* " It must not be overlooked that the liberation of force is not de 



