1-54 NUTRITION. 



curd of milk, called by chemists, Casein, are analagous to muscular 

 fibre. They are all analagous, also, to the gluten and legumin of wheat 

 and other grains, and, like them, contain fifteen per cent, of nitrogen, 

 and a little sulphur or phosphorus, or both. 



c. The fat, which in an animal in good condition, forms nearly one- 

 third of the weight of the soft parts of the body. It is very analogous 

 — in some cases absolutely identical — with the fatty matter of the vege- 

 table food. Comparing the organic parts of both we have 



In the plant, Animal, 



1. Cellular substance, 1. Cellular substance — Gelatine, Chondrin, 



2. Gluten, Albumen, &c. 2. Febrin, albumen, 



3. Fatty matter, 3. Fatty matter. 



4. Starch, gum sugar. 



This comparison shows us, that in both animals and vegetables there is 

 a cellular substance performing analogous functions in each, though of 

 unlike composition — that in both there are substances, gluten and fibrin, 

 which are almost identical ; the fats, which are often absolutely identi- 

 cal — and that the only marked difference between them consists in the 

 large quantity of starch, &c. which is present in vegetable food. 



We can now understand what are the functions which the plant has 

 to perform in reference to animal life, and what purposes are secured by 

 the several constituents of the vegetable food which we eat. The plant 

 has to manufacture the materials — the gluten and fat — out of which the 

 soft parts of the animal are to be built up. 



Then as to the purposes of the several constituents of the food, — 

 the gluten is carried into the stomach, and thence to the proper parts of 

 the body to build up almost unchanged the muscular parts of the body. 

 The fat is transferred to the proper localities. The plant thus becomes 

 administrative to the animal necessities. 



A very close connection is shown thus between the vegetable and 

 animal kingdoms, and the dependence of the latter on the former is 

 complete. 



Moreover the principal difference between plants and animals is in 

 the starch of the former, which is necessary in some of the animal pro- 

 cesses. The fundamental substance in all the articles mentioned is Pro- 

 tein. It is the leading constituent in Gluten (of wheat,) Fibrin of mus- 

 cles. Albumen of blood. Casein or curd of milk, hair and wool. Sul- 

 phur and Piiosphorus being other constituents in different proportions. 



The results of the investigations of Professor Mulder (of Utrecht.) 

 on these subjects are deserving of the particular attention of all interest- 



