"What is the object of cultivating the soil?What is necessar y in order to cultivate with economy?Are plants created from nothing?The object of cultivating the soil is to raise from it a crop of plants. In order to cultivate with economy, we must raise the largest possible quantity with the least expense, and without permanent injur y to the soil.Before this can be done we must study the character of plants, and learn their exact composition. They are not created by a mysterious power, they are merely made up of matters already in existence. They take up water containing food and other matters, and discharge from their roots those substances that are not required for their growth. It is necessar y for us to know what kind of matter is required as food for the plant, and where this is to be obtained, which we can learn only through such means as shall separate the elements of which plants are composed; in other words, we must take them apart, and examine the different pieces of which they are formed"
