Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: CHAPTER III. AGRICULTURAL GEOLOGY. BY WM. M. FONTAINE. Under this head, we will give a brief description of the several geological formations found in the State, dealing with them, in their agricultural relations mainly. As, however, topography is so intimately connected with agriculture, we may in this connection, note those special features, not elsewhere, noticed. But bef re taking up the Geological Formations, it will conduce to clearness if we first give some account of the charac ter of the different soils, and of the rocks which form them. THE DIFFERENT SOILS. The following are the principal soils existing in the State: Clay Soils.—These contain 75 per cent., and over, of clay. The remaining 25 per cent., is composed of sand, calcareous, ferruginous, vegetable, and other matters. In their physical character, when moist, they are stiff and tenacious. They dry with difficulty, and are rather slowly warmed by the sun's rays. When dry, they become baked to a more or less hard mass, and are also, in freezing and thawing, more apt to injure the roots of plants, than other soils. With these disadvantages, however, they combine many advantages, and when properly managed, make, the best lands for certain crops. Stiff Clays.—Such as those just described, do not make a large proportion of our soils. They are chiefly to be found in the eastern and southern parts of the State. Sandy Soils.—Contain 75 per cent., and over, of sand. The remaining components are clay, and the other constituents, except sand, mentioned as occuring in clay soils. In their physical characters, they are the opposite of clay soils, and are much inferior to them. They are loose, thirsty in nature, and do not hold manures well. Hence, a mixture of sand and clay in land is beneficial, th...