MANUAL OF OATTLE-FEEBINO. 226 



stances wliicli are formed are supposed to be rapidly ex- 

 creted, while tlie nitrogenous product, instead of undergo- 

 ing further deconipositioUj is used over again to re-form 

 the hypothetical substance. 



This view has much in its favor. Yarious syntheses, 

 more or less like that above outlined, are known to take 

 place in the body ; and, moreover, we have seen that all 

 the facts seem to indicate that muscular force originates in 

 a splitting up of some substance in the muscle, rather tlian 

 in any process of oxidation in the ordinary sense of the 

 word. 



The hypothesis explains the object of the storing up of 

 oxygen in the body during rest, and its connection with 

 the laying up of a reserve of force : the oxygen enters into 

 the supposed complex compound much as the nitric-acid 

 radicle enters into nitro-glycerine or gun-cotton — it is held 

 in a state of unstable equilibrium, ready to enter into new 

 and simpler relations with its neighboring atoms and to 

 set free the force by which it was placed in its unstable 

 position. The. hypothesis also brings that necessity for 

 albuminoids in the food of tlie laboring animal which 

 practical experience has shown to exist, iato harmony with 

 the fact that there is no greater excretion of nitrogen dur- 

 ing work than during rest. Furthermore, it shows why 

 we need rest after work. In the first place, the circula- 

 tion must have an opportunity to remove those waste 

 products which accumulate in the working muscle faster 

 tlian they can be carried off, and in the second place a 

 fresh supply of force must be stored up in the way des- 

 cribed before it is ready to be used at the command of the 

 will. 



Finally the assumption of a complex " contractile mate- 

 rial" is in harmony with the results obtained by Fick & 

 10* 



