FOOD OP MAN AND OTHER ANIMALS. 128 



holding about six quarts of fluid. This when filled is 

 closed up by a muscular band, and employed not only 

 for shooting at flies, but also to moisten the contents of 

 the stomach if occasion requires. 



THE FOOD OF MAN AND OTHER ANIMALS. 



It is the object of this work, not only to convey to 

 the minds of youth such a knowledge of Comparative 

 and Human Physiology, as may be useful to them for 

 the common purposes of life ; but also to instruct them 

 in the application of these principles to their own per- 

 sons, so far at least as the functions of the stomach, 

 muscles, and brain are concerned. With this view it is 

 proposed here to inquire into the subjects of food and 

 digestion, more particularly than we have done ; what 

 we have said of the digestive process in man being only 

 an introduction to what follows. 



Elements of Nutrition. Chemistry has taught us 

 that the most important principles of diet, derived from 

 animal substances are fibrin, albumen, jelly, osmawme, 

 and oil. Fibrin is the muscular fibre, composing the 

 lean parts of all meats ; albumen, or coagulable lymph 

 composes a part of the blood, and is abundant in the 

 animal system, The white of an egg is nearly pure 

 albumen ; jelly and oil need no description ; osmazome 

 is a peculiar juice, or extractive matter, which is not 

 coagulable by heat, and on which the flavor of different 

 meats depends. It probably consists of a portion of the 

 fibrin slightly altered by the heat. 



Food, Nutritive and Digestible. Articles of food may 

 be considered in two respects, viz. as nutritive and 

 digestible. Substances are nutritive in proportion to 

 their capacity to yield the elements of chyle ; they are 

 digestible in proportion to the facility with which they 

 are acted upon by the gastric juice. Between these two 



What are the nutritive parts of animals 1 What is albumen 1 What 

 is osmazome'? In what proportion are substances nutritive 1 In what 

 proportion are they digestible ? 



