54 THE CHEMISTRY OF FOOD. 



3. Again, certain forms of the vegetable creation which 

 are unfit, in their crude state, for man's food, and which he 

 rejects, are chosen as food by some of the lower animals, 

 and are, by them, made ready for his use. Thus the bee 

 takes the clover, that man cannot eat, and from it collects 

 honey. The cattle eat the husks of corn and the dried 

 grass, that are by far too coarse for man, and in their own 

 flesh convert them into tissues closely resembling his mus- 

 cular tissue. In this way, by the aid of the transforming 

 processes of the vegetable and animal creations, the simple 

 chemical elements of the mineral kingdom are elaborated 

 into our choice articles of food. 



4. Tnorganic Substances. The substances we use as 

 food are classified as organic and inorganic. By organic 

 substances are meant those derived from living forms, such 

 as vegetables and animals. Inorganic substances are those 

 simpler inanimate forms which belong to the mineral 

 kingdom. The former alone are commonly spoken of as 

 food, but the latter enter very largely into the constitution 

 of the body, and must therefore be present in our food. 

 With the exception of two articles, water and common 

 salt, these substances only enter the system when blended 

 with organic substances. 



5. Water. Water, from a physiological point of view, is 

 the most important of all the articles of food. It is every- 

 where found in the body, even in the bones and the teeth. 

 It has been computed that as large a proportion as two- 

 thirds of the body is water. The teeth, the densest of the 

 solids in the human system, contain ten per cent, of water. 

 The muscles, tendons, and ligaments are more than half 

 water; for it is found that they lose more than half their 



3. Certain forms of vegetable creation? Example of the bee? Cattle? The 

 inference ? 



4. What classification ? Define organic substances. Inorganic. Organic, 

 how spoken of? The inorganic ? Water and salt ? 



5. Water in physiology ?"' Where found ? Computation? Water in the teeth? 

 Muscles, tendons, and ligaments ? How ascertained? Water in the fluids of the 

 body ? What is the advantage ? 



