270 



PHYSIOLOGICAL CHEMISTRY. 



uted to them by LIEBIG in muscular activity; but when we con- 

 sider that from the albuminous bodies not only the fats proceed but 

 also the carbohydrates, glycogen, it is difficult to see why the 

 source of muscular force is not in part due to a metabolism of the 

 proteids. Though it is probable that in work the carbohydrates in 

 the first place, and then the fats, are consumed by an increased 

 exchange, it is therefore not improbable that the albuminous bodies 

 also take part, and that all three chief groups of organic foods or 

 muscle-constituents undergo an increased exchange during activity 



Quantitative Composition of the Muscle. A large number of 

 analyses have been made of the flesh of various animals for purely 

 practical purposes, in order to determine the nutritive value of 

 different varieties of meat; but we have no exact scientific analyses 

 with sufficient regard to the quantity of different albuminous 

 bodies and the remaining muscle-constituents; or these analyses 

 being incomplete are of little value. 



To give the reader some idea of the variable composition of 

 muscle-substance we give the following summary, chiefly obtained 

 from K. B. HOFMANK'S book. The figures are parts per 1000. 



Muscles from Mammalia. Birds. Cold-blooded 



Solids ............................. 217-255 227-282 200 



Water ........................ ... 745-783 717-773 800 



Organic bodies ................... 208-245 217-263 180-190 



Inorganic bodies ................... 9-10 10-19 10-20 



Myosin .......................... 35-106 29.8-111 29.7-87 



Stroma substance (DANILEWSKY) ---- 78-161 88.0-184 70.0-121 



Alkali albuminate ................. 29-30 



Creatin ........................... 2 3.4 2.3 



Xanthin bodies .................... 0.4-0.7 0.7-1.3 



Inosinic acid (barium salt) .......... 0.1 0.1-0.3 



Prottc acid ........................ 7.0 



Taurin ..................... ....... 0.7 (horse) 1.1 



Inosit ............................. 0.03 



Glycogen ......................... 4-5 3-5 



Lactic acid ....................... 0.4-0.7 



Phosphoric acid ................... 3.4-4.8 



Potash ........................... 3.0-4.0 



Soda ............................. 0.4 



Lime ......... ................... 0.2 



Magnesia ......................... 0.4 



Sodium chloride .................. 0.04-0.1 



Iron oxide ........................ 0.03-0.1 



