CHAPTER IX.

Animal Manures—Their Relative Value and Mode of Action—Difference between Animal and Vegetable Manures—Cause of this Difference—Mineral Manures— Nitrates of Potash and Soda—Sulphate of Soda, Gypsum, Chalk, and Quicklime—Chemical Action of these Manures—Artificial Manures—Burning and Irrigation of the Soil—Planting and Laying Down to Grass. 165