444: THE STATISTICAL METHOD. [BOOK n. 



An analysis of a cat has given the following result : 



Muscles and tendons 45*0 p. c. 



Bones 147 



Skin 12-0 



Mesentery and adipose tissue 3*8 



Liver 4*8 



Blood (escaping at death) 6*0 



Other organs and tissues 13*7 



One point of importance to be noticed in these analyses is that 

 the skeletal muscles form nearly half the body; and we have 

 already seen (p. 34) that about a quarter of the total blood in the 

 body is contained in them. We infer from this that a large 

 part of the metabolism of the body is carried on in the muscles. 

 Next to the muscles we must place the liver, for though far less in 

 bulk than them, it is subject to a very active metabolism, as 

 shewn by the fact that it alone may hold about a quarter of the 

 whole blood. 



The Starving Body. Before attempting to study the influence 

 of food, it will be useful to ascertain what changes occur in a body 

 when all food is withheld. A cat was found to lose in a hunger 

 period of 13 days 734 grammes of solid material, of which 248*8 

 were fat and 118*2 muscle, the remainder being derived from the 

 other tissues. The percentages of dry solid matter lost by the more 

 important tissues during the period were as follows : 



Adipose tissue 97'0 p. c. 



Spleen 63'1 



Liver 56*6 



Muscles 30*2 



Blood 17-6 

 Brain and spinal cord O'O 



Thus the loss during starvation fell most heavily on the fat, indeed 

 nearly the whole of this disappeared. Next to the fat, the gland- 

 ular organs, the tissues which we have seen to be eminently 

 metabolic, suffered most. Then come the muscles, that is to say, 

 the skeletal muscles, for the loss in the heart was very trifling; 

 obviously this organ, on account of its importance in carrying on 

 the work of the economy, was spared as much as possible : it was 

 in fact fed on the rest of the body. The same remark applies to 

 the brain and spinal cord; in order that life might be prolonged 

 as much as possible, these important organs were nourished by 

 material drawn from less noble organs and tissues. The blood 

 suffered proportionally to the general body-waste, becoming gra- 

 dually less in bulk but retaining the same specific gravity; of 

 the total dry proteid constituents of the body 17'3 p. c. was lost, 



