PRESIDENT HITCHCOCK'S ADDRESS. 165 



liberated, and mineral or inorganic matter becomes organized, 

 that is, converted into the various parts of the plant. The chem- 

 ist cannot, indeed, look into all the crucibles, and retorts, and 

 flasks which nature employs in this curious laboratory, nor ex- 

 amine all the re-agents, because they are too minute ; but he 

 can see enough to show that the whole is a chemical process, 

 modified somewhat by the vital principle. He can see enough to 

 make him strongly desire to see more ; enough to make him 

 feel how infinitely superior is nature's chemistry to his own. 



The analysis of the various parts and products of plants has 

 disclosed some most curious facts as to their great similarity, 

 and their relation to the principles found in animals. It has 

 been ascertained that animals need two sorts of food ; one kind 

 containing nitrogen, and another sort destitute of it. Those 

 principles containing nitrogen are necessary for their nourish- 

 ment, and are found to be three, called albumen, fibrine, and 

 caseine ; which are the same essentially in composition. Those 

 principles destitute of nitrogen are necessary to sustain the pro- 

 cess of breathing, and thus to furnish fuel for keeping up the 

 animal heat. These are fat, starch, sugar, gum, &c. Now all 

 these principles, both for giving nutrition and keeping up the 

 animal heat, exist ready formed in vegetables, and, when vegeta- 

 bles are taken for food, the animal merely appropriates the prin- 

 ciples, but does not change them. Thus fat exists in the oily and 

 waxy parts of vegetables; starch and sugar occur abundantly 

 in many plants; and the fibrine, albumen and caseine, are derived 

 from the gluten of flour, the leguminous principle of beans, &c. 

 It needs nothing, also, but water and the oxygen of the air, to 

 convert these various principles into one another ; and some- 

 times this can be done even by man. Thus, starch is easily 

 changed into sugar, and very palatable bread has been made 

 out of wood, which, in fact, is chiefly fibrine, and contains all 

 that is essential for nourishment. Who knows how soon it may 

 happen, that a few cords of wood shall furnish the poor man 

 not only with fuel, but with bread? 



It is obvious that these curious facts have an important bear- 

 ing upon several questions relating to the food best suited to man. 

 They show us, in the first place, that whether a man eats vege- 



