SCIENCES APPLICABLE TO FARMING. 51 



ated, and mineral or inorganic matter becomes organized, that 

 is, converted into the various parts of the plant. The chemist 

 cannot, indeed, look into all the crucibles and flasks which 

 nature employs in this curious laboratory, nor examine all the 

 reagents, 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, such as albifmen,fibrine, hamatin and caseine, which are 

 the same essentially in composition. Those principles destitute 

 of nitrogen are necessary to sustain the process of breathing, 

 and thus to furnish fuel for keeping up the animal heat. These 

 are fat, starch, sugar, gum, &c. Now these principles, both 

 for giving nutrition and keeping up the animal heat, often exist 

 ready formed in vegetables, and when vegetables are taken for 

 food, the animal merely appropriates the principles. Thus fat 

 exists in the oily and waxy parts of vegetables ; starch and 

 sugar occur abundantly in many plants ; and the fibrine, albu- 

 men 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 prin- 

 ciples into one another ; and sometimes this can be done even 

 by man. Thus, starch is easily changed into sugar, and very 

 palatal )le 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 ? 



These theories of nutrition and animal heat cannot be 

 regarded as completely established. But they are so much 

 more ingenious and satisfactory than any which have preceded 

 them, as to give them strong claims upon our attention. 



Geology teaches us that soils are nothing but rocks crushed 



