422 



PHYSIOLOGY AND MORPHOLOGY OF ANIMALS. 



I have constructed the following diagram to illus- 

 trate this process (Fig. 294) : 



Animal Life 



Fig. 294. — Diagram illustrating the generation of animal heat and 

 animal force. 



We have represented here three planes raised one- 

 above the other, viz., (1) the plane of the mineral king- 

 dom, (2) the plane of food, and (3) the plane of living 

 tissue. The plane of food is subdivided into a lower and 

 a higher. The lower form of food — viz., the amyloids and 

 fats — is at once burned without residue; the whole of it 

 runs down to the mineral kingdom C0 2 and H 2 * and 

 generates a corresponding amount of force. The higher 

 form of food, albuminoids, if in excess of the necessities 

 of repair and growth, also runs down, but in its down- 

 ward course is split (see Fig. 293 on page 420) into (a) a 

 combustible portion which is burned to C0 2 and H 2 0, 

 and eliminated by the lungs, and (b) an incombustible 

 portion which is eliminated on a little higher plane as 

 urea by the kidneys. Another portion of albuminoid 

 food is raised to the plane of living tissue for repair 

 and growth, and after remaining on that plane and 

 playing its part there for a time, also runs down as 



* In the diagram we have used only CO a , because this really 

 gives the amount of force, the H and the O being already in the 

 food in proportions forming H a O, and therefore supplying no 

 heat or force. 



