Manures are of two classes--called putrescent and fossil. The putrescent are composed of decayed, or decaying, vegetable and animal substances. The fossil are those dug from the earth, as lime, marl, and gypsum. All vegetable substances not useful for other purposes are valuable for manure. Rotten wood, leaves, straw, and all the vegetable parts of stable manure, and any spoiled vegetables or grain, are all valuable. At the South, their immense quantities of cotton-seed are a mine of wealth, if properly prepared and applied as manure. Animal manures consist of the animal parts of stable manure, dry and liquid, parts of bones, brine, spoiled meat, kitchen slops, soapsuds, and all dead animals. In decaying, these substances all pass through a process of fermentation. Left exposed without suitable care, they become unhealthy and offensive. It is probable that a large share of the diseases suffered in the rural districts are caused by these impurities; and the impossibility of keeping large cities free from these substances is the cause of their increased mortality. In the country, a little timely caution and labor, in removing these substances and regulating their fermentation, would save much sickness; while the labor would pay a larger per-cent. profit than any other performed on the soil. No manures should be allowed to ferment, or decay, without being mixed or covered with enough common earth, sand, peat, or muck, to retain all the gases and exhalations of such putrescence. The smallest quantity that will answer is one load of earth to two of the decaying substances. The proportions reversed would be better: put one bushel of lime to two loads, two quarts of ground plaster, and half a bushel of ashes, and you have the very best compost heap. The following are brief general rules for the preparation of manures. It is always most economical to feed cattle in the stable or under cover, and never have manure exposed to the weather. But if cattle must be fed outdoor, let them be fed in a yard, lowest in the centre, that the liquids and washings may run into the centre, and be absorbed by straw and litter. Put manure on the land, or into heaps for compost, before very warm weather. Always feed sheep under cover, and keep their manure from rain; heap it together with earth in the spring, or apply it to the soil at once. Manure thrown out of a stable should be kept under cover, out of the rain, and not allowed to heat in winter; its best qualities are evaporated by fermentation in the yard. Manures often rained on in winter, or left in large piles without intermixture of earth, lime, plaster, and ashes, will ferment and waste. Construct your stables so that the liquid manure will run into a vat filled with earth; muck is best. Experiments have shown that the liquid manures are at least one sixth better than the solid. A gentleman dug a pit, thirty-six feet square and four feet deep, and walled it in on all sides. He filled