12 



HITCHCOCK'S AXATOMY 



tion with other substances, and as oil drops or fat globules 

 not inclosed. These principles are mostly taken as food into 

 the system, but they are most probably also formed there 

 from elements ; certainly, the liver has this power. One 

 tenth of the brain is composed of fat ; and it is only in the 

 last stages of emaciation, that this supply is exhausted. 



81. Assimilation Necessary. — The principles thus far de- 

 scribed, constitute but a small proportion of the animal frame. 

 13 at the organic, or coagulable principles, enter largely into 

 its composition. Indeed, they form the principal source of 

 nourishment. The most important of these principles (albu- 

 men, fibrine, and caseine) are in a fluid state in the body; 

 tlio others are solid, or demisolid. Though the materials for 

 their formation must exist in the food, yet there is reason to 

 suppose that the process of assimilation is necessary, to trans- 

 form them into these principles. 



82. Albumen, A lb ami nose, Caseine. — Coagulation takes 

 place when a liquid, or semi-liquid, passes into a solid state. 

 The white of an egg gives a good idea of one kind of albumen 

 (ovalbumen). Seralbumen exists in the blood, and in other 

 liquids of the body. Alb umi nose is found in the same fluids, 

 and has been, till of late, confounded with albumen. It is 

 formed in the upper intestines, but when it passes into the 

 blood, it becomes mostly albumen, sometimes musculinc, 

 fibrine, etc. Animal caseine is found only in milk, being 

 most abundant when an animal diet is used. It contains from 

 four to six per cent, of phosphate of lime, and hence the im- 

 portance of milk for young animals, that their bones may be 

 developed. 



33. Fibrine, Musculinc, Globuline, Ostcinc, and Gluten. — 

 Fibrine is found in the blood, and when it coagulates, the mass 

 h fibrous, the process being called fibrillation. It is this prin- 

 ciple chiefly that causes blood to coagulate, the great importance 



Is fat formed in the body, or taken in from the food? 31. State the three most im- 

 portant organic principles. 32. Define coagulation. What is ovalbumen, seralbumen and 

 albuminose? In what is caseine found ? What important ingredient does it contain? 

 33. Where is fibrine found ? What causes coagulation of the blood? What practical b«ne» 

 fit is derived from coagulation ? 



