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holds, and in its manner of receiving and emitting that fluid,holds a medium between sand and clay ; and consequently, insome measure, remedies the deficiencies of both. Though, a-lone, it is unfriendly to the roots of plants, experience has taughtus, that it is a valuable ingredient in the soil, and must thereforebe of more importance, the more intimately it is mixed with theother ingredients. This is, no doubt, most effectually done, byspreading it in powder on fallowed ground, and thoroughly mix-ing, by ploughing and harrowing as above. But in the practiceof convertible husbandry, where much ground is kept in grass,and less in summer fallow, lime is frequently spread on pasture-ground. When this is done early in autumn, and the lime inpowder, by suffering it to lie till the grass grow through it, andattach it to the surface, it may be pretty well mixed in the courseof a tillage rotation, provided the first ploughing be shallow andnarrow, and the mixing promoted by ploughing and harrowingacross, in the course of the rotation. While it lies on the sur-face, the soil being sheltered from the storm, and the escape ofthe subterraneous heat checked, it is mellowed. The lime, ciungfast to the surface, and smothered by the growing herbage, inthe damp and stagnant air, becomes like decayed plaster, dispos-ed to mingle easily with the other earths, and perfect the soil forcherishing the roots of plants.
3d, To facilitate the decomposition of putrescible substances,was the third purpose stated for applying lime to the soil. A.reason is stated above, for strongly suspecting the putrefyingpower of effete lime. But it has been also observed, that quicklime, with the assistance of water, suddenly decomposes all ani-mal and vegetable bodies. This is fairly exemplified, when quicklime lias been spread on neglected ground, covered with mosses,heath, and other coarse herbage. The old turf is putrefied, thehydrogen and carbon of its composition combine with the solu-tion of the lime, and form a saponaceous matter, the ready nour-ishment of plants. This sinks into the soil, and white clover andother sweet herbage soon cover the surface. Whenever suchgrounds have an even surface, this is probably the most econo-mical way of bringing them into culture ; and must be appliedwith more advantage on pasture-ground, which has a close turf,than any other mode: and the advantage is still greater, whenthe lime lies for a season or two to mellow the soil. But, whe-ther quick or effete, lime neutralizes the different acids contain-ed in vegetables, the antiseptic quality of which retards their pu-trefaction ; and thus the decomposition which converts them intovegetable food is facilitated.
It may here be added, that besides the indirect aid which limegives to the growth of plants, it perhaps contributes a little totheir direct increase. The proneness of lime to unite with theacids has been noticed: with some of them it forms insoluble