344 Mr. C. W. Heaton on the Function of 



Metrekilogrammes. 



Heart 70,000 



Lungs 10,000 



Voluntary muscles . . 20,000 



100,000 



To do even this small amount of work, double the quantity, 

 or 200,000 metrekilogammes of force, must be developed (Hei- 

 denhain). Now 22*88 grammes of oxygeu would oxidize — 



7*89 grms. of fat, taken as having average composition of 

 oleine, margarine, and stearine (Lawes and Gilbert), 

 or 15*39 grms. of muscle, taken as equal in composition to 

 albumen. 



Multiplying these quantities by the force-values obtained by 

 Frankland*, we obtain these figures : — 



Metrekilogrammes. 

 Fat . 7-89x3841 . . =30,305 

 Muscle 15*39x1848 . . =28,440 



So that, even upon this extravagant calculation, we see that 

 whether it oxidized fat or muscle, the oxygen exuded could not 

 account for one-sixth of the work done by the muscles. To 

 give even the 200,000 metrekilogrammes of force there must be 

 a daily exudate of 264 litres, or more than a quarter of a ton of 

 arterial corpuscles ! 



I think it is therefore certain that all, or nearly all, the force 

 of the body is generated in the blood, and that Mayer was per- 

 fectly right in saying that " the muscle produces mechanical 

 effect at the expense of the chemical action expended in its capil- 

 lary vessels." Hence it is natural to inquire what modification 

 this view compels us to make in our ideas of muscular disinte- 

 gration. 



In the first place, it forces us to admit that this disintegra- 

 tion is a simple decomposition, and not an immediate oxidation. 

 When a muscle suffers disintegration, either by natural change 

 or during muscular work, two classes of compounds are known to 

 be produced. The members of one class are ternary and contain 

 the residue of water, while those of the other are quaternary and 

 contain directly or indirectly the residue of ammonia. To the 

 former class belong the fatty acids, lactic acid, sugar, &c, 

 and to the latter such bodies as leucin, creatin, creatinin, uric 

 acid, and urea. The greater portion of these products of de- 

 composition are probably carried to the blood by the lymphatics ; 

 and some of them, notably sugar, leucin, and urea, have been 

 discovered in the lymph. The oxidation in the blood of such of 



* Phil. Mag. September 1866. 



