LIME. What is generally understood by the term lime is quicklime, the protoxide of calcium, produced by burning limestones or sea-shells in the free draft of a fire. The process of calcina tion, drives off .the carbonic acid contained in the limestone. If fresh burned lime be kept from access of air and moisture it will retain its condition unchanged: Its affinity for moisture, however; renders this difficult. Quicklime does not absorb carbonic acid from the atmosphere until it has first absorbed moisture. It then absorbs carbonic acid, and becomes a combined carbonate and hydrate of lime. For agricultural uses, lime is used air-slacked, after being burned, in which state it is a fine powder. Its mechani cal action is to render heavy soils more porous,• and light soils more tenacious. It does not act chemically on soils when freshly burned, and hence it is often mixed with three or four times its bulk of earth and spread upon the surface of the land. The weight and exceeding fineness of lime causes it to sink in the soil, hence it should always be applied near the surface. Lime is not a manure. It does not bring plant food to the soil, but assists that which is there for vegetable nutrition. It produces physical conditions en abling plants to assimilate the nutrition already in the soil. Hence the effect of lime on rich soils deficient in lime, and hence also the fact, that lime should not be used except in connection with other fertilizers, since one of the principal actions of lime is to convert insoluble matter of the soil into available plant food. Sometimes its effects are surprising upon worn soils. In this case it may he inferred that the fertility was then but locked up in an insoluble condition, a not by any means uncommon of things. Hence the well known adage that, the only way to know if land wants lime is to try it., Theoretically a soil should contain three per cent. of lime, in connection with the percentage of vegetable matter and other plant food. The following table shows the am nint in tons neces sary to add from one-quarter of one per cent. to four per cent. of lime as it comes from the kiln, to a soil at the varying depths three, six, nine, and twelve incises in depth.
The quantity generally applied is from four to twelve bushels per year, or from twelve to fifty bushels every three years. Lime is always found in plants, not as pure lime but chiefly as the carbonate, phosphate, or sulphate of lime, that is in combination with acids. Therefore, when it is found that a soil does not contain three per cent. of lime, it should be added. Prof. Way has determined the amount of lime in various plants; in 100 parts of the ash of the following plants, he found : Of the grain of the creeping wheat 6 76 Of the straw and chaff 7.46 Of the gi am o f chevalier barley 148 Of the grain of potato-oats 131 Of the chaff of oats 8 65 Of the grain of rye 2 61 It is recorded as noticeable that the amount of lime present in the ash of various specimens Df wheat was the most considerable-8.21 per cent.
in some Hoptoun wheat grown on silicious sand, and that in another specimen of the same wheat grown on a chalk soil, the ash only con tained 1.83 per cent. of lime. In the ash of various green crops, Prof. Way found, in 100 parts, the following amount of lime: The amount of lime in the red and white clover did not vary in different specimens grown on silicious or clay soils. It would have been $asonable to expect a large proportion of lime ill the sainfoin, which flourishes best in a cal cOeous soil. The specimen, however, analyzed by Prof. Way was grown on a light gravelly loam, with a subsoil of gravel above chalky clay, In a ton of the ordinaryroots and legumes (the entire plant) Prof. Way found .the following amount of lime: The following analyses of six samples of lime will enable the reader to get a good idea of the constituents: So that, as the professor remarks of the roots, twenty tons of bulbs and four tons of tops will require of lime: An analysis of hydraulic limestone gave the following results: Insoluble in acid, 27.49 per cent., consisting of: .The ash of the various natural grasses was found by Prof. Way' to contain from 14.94 per cent. (the Phleum pratense) to 3.94 (the Alopecurus pratensis;) in that of the artificial grasses he found from 45.95 per cent. (the Medicago sativa) to 13.40, (in the Aehillea millefolium). It is noticeable that the amount of lime present in a plant varies considerably in its different portions. Thus, the ash of the Kohlrabi contains 10.20 per cent. in that of the bulb, but 30.31 in the ash of the leaves. The ash of the root of the carrot yielded 5.64 per cent of lime, that of the leaves 24.04. The ash from the flowers of the hop 9.59 per cent., that from the leaves 30.73 per cent., that from the vine 23.71. The ash of the potato analyzed by Prof. Way contained in that of the tubes 4.50 per cent., in that of the haulm 29.86. The action of lime when applied to soils abounding in inert, organic matter, like the peaty, is not only to furnish a supply of lime to the plants which tenant such soils, but caustic lime tends to bring any dead vegetable matters which they contain into a state of decomposition, so as to render them more soluble in water, and so more available as food for growing plants. It is in this way that we account for the success of the mixture of lime with the scrapings of ditches, collections of weeds, pond mud, etc. This compound, after allowing it to remain in a heap for two or three months has been found to be a very useful manure, and acting quickly. It should be distinctly remembered that lime must never be applied as a part of the compost with fermenting manure, unless muck enough is used to take up the ammonia set free, since the effect of lime is not to fix ammonia, but to free it; to fix it, copperas or gypsum is to be used. This requires to be well remembered, for nitro $en is one of the most important and expensive in the whole category of substances necessary in the soil when maximum crops are to be raised.