The natural fertilizers have been analyzed, and artificial nutrients of the soil have been contrived.

In our own times, and among civilized peoples, bread has become an article of food of the first necessity; and properly so, for it constitutes of itself a complete life-sustainer, the gluten, starch, and sugar, which it contains, representing azotized and hydro-carbonated nutrients, and combining the sustaining powers of the animal and vegetable kingdoms in one product.