1132 PHYSIOLOGY 



capillary pressure which results from the bleeding. The abstraction 

 of fluid from the tissues is responsible for the extreme thirst which is 

 the result of haemorrhage, and which directs the animal to take up by the 

 alimentary canal the fluid which is wanting to the body. The transfer 

 of fluid from tissues to blood is extremely rapid ; even during the 

 course of a bleeding it is found that the later samples of blood are 

 more dilute than those obtained at the beginning. This mechanism 

 suffices only to make up the supply of circulating fluid. After a 

 bleeding, however, an animal has lost proteins and blood-corpuscles, 

 and these constituents of the blood are but slowly restored, the former 

 directly from the food, the latter by an increased activity of the blood- 

 forming cells in the red marrow. 



