Liquid manure, however active and immediately effective, aeon loses its power ; whereas solid dung, well prepared and ploughed into the ground, will last for several crops. It is the judicious use of both these manures, conjointly, which has the best and more permanent effect. The dung or compost, having been ploughed in well requires some time before it can have any direct effect on tho germina tion of the seed or the nourishment of the plant. The liquid, on the contrary, acts from the moment it is poured on the surface. It is the milk of the young plant, which thrives upon it and stretches nut it fibres through the earth, till it reaches the dung, which is now in r proper state to 'supply the more vigorous roots with sufficient nourish meat. It is evident that the growth must be more rapid and regular and not so liable to be chocked from want of proper nourishment, not are the young roots In danger of perishing by being too soon to the immediate contact of rank dung. Every exertion should there fore be made by the Induatrious 1ioslandman to increase the quantal and improve the quality of every species of manure both solid an liquid : and here careful experiment can alone be depended upon.
In the formation of composts the princilm1 objects are, to regulate the degomposithiti of the ()manic substances, and to increase the bull of the manure by means of lean expensive materials than straw. Fo these purposes lima or chalk is generally used : the former, in it caustic state, to accelerate the decomponition of fibrous matter ; the latter to add to the masa, and absorb any portion of acid, which i always produced in a certain stage of the fermentation. The mode o doing this Is so generally known. that it is needless to describe it : ere shall only observe that the stiffest clay may be used with adrantage ii composts, where better veil is not at hand ; and for light lands, th stiffer the clay the butter, provided it be thoroughly incorporated with the manure. The most useful materiel, under proper management, i vegetable moil or turf. This may be laid in layers with quick-lime ani earth ; the whole being well snaked with liquid manure. If any kite of vegetable matter, such as tern, pond-wmds, &c., can be addsl, it wil xs eo much the richer. The lime and urine acting deeon;)os) and random it, the woody fibre is disselved, and the whole mass, when ,urneel over and well mixed, becomes a very rich' earth, which, being Tread on the land and slightly ploughed or harrowed in, greatly uiriches its surface. By this means many poor soils may be ini uuved, where the cultivation is net sufficiently extended to produce straw.
Although bones have been treated of in a separate article [BONES], it may be proper to mention here, that if some easy means of dissolving their substance were discovered, they might be mule of much greater use than they now arc. At present they are put in with the seed in a broken state, and as they remain a long time undecomp osed in the soil, their effect, after the last crop, is scarcely perceptible, unless a very large quantity is used. By mixing dissolved bones iu a liquid state with earth, almost all the component parts of urine would be there.
[We leave the preveding sentence as written many years ago by Mr. Idham, that he may have the credit of so early a prediction of the result which has actually followed the discovery of the method here discussed. In the article on BONES, Baron Liebig's method of dis
solving them, which is now in universal practice, is described.] Besides an immense number of waste substancesnow used in manure, we have, in guano and other imported fertilisers, means of replenishing our soils of which the agriculturists of thirty years ago knew nothing, and to some of them we must now make some reference. But, first, it may be named, that the ashes of vegetable substances which have been burnt are very effective in stimulating veg,ttation. They are chiefly used as a top-dressing on young clovers and grasses ; and wherever there is an appearance of gourmess in the grasswood-ashes are of great use. It is however seldom that wood-ashes are used as manure until the greater part of the alkali has been extracted; but when the surface of the laud is pared off, and the dry sods are burnt, the ashes %shied., result from this operation are very effective in producing a good crop without any other manure. (BARING AND BURNINO.l The refuse ashes from bleachers' and soap-boilers' premises have still some portion of alkali in them, and, as they contain limo and other earths in a eery divided state, their effect on the soil is very perceptible. Sea-salt hag been extolled and decried at different times, owing probably to the different circumstances under which it has been tried. Mangold-mired undoubtedly benefits by its application ; and one or two ew•ts, per acre, in inland situations, will benefit other crops as well. Quick-lime slaked with salt water is a powerful manure.
It is hardly consistent with the character of this Cyclopedia that instruction should be given in extreme detail on the source and supply of the manures of the farm, but the eonchtsion may be named, that on well-managed land, cultivated on the alternate system of cropping, where;at, least one-half the land grows grain, there will be a supply of from 3 to 4 tons of dung per acre, according to the rotation adopted, and certainly not more than 5 tons, even under good management, and heavy crops. But what is wanted under such a rotation? Suppose it to be a six years course of cropping, namely,-1, wheat ; 2, beans ; 3, wheat; 4, swedes ; 5, barley ; clover. There are at any rate two crops to which dressings of farm-yard dung are desirable,— namely, beans and swedes ; and in England, the clover, also, either before it has yielded its crop or after it, for the wheat often then receives a dressing. In the former ease 100 acres:and in the other 150 acres, on a farm of 300, have to receive a dressing of manure. A quantity equal to 1000 tons is all that can be expected, and the 10 tons of dung, which is all that can be given per acre, according to the one syetem—the 7 or 8 tons per acre, which is all that it provides in the other case—are a very imperfect dressing indeed. What is wanted, in .order to a thoroughly liberal treatment of the land ? On 50 acres of clover, 500 tons of yard manure are wanted ; on 50 acres of beans, 750 tone of yard manure are wanted, besides at least 71y tons of guano. Over the 50 acres of turnips we want, 750 to 1000 tons of farm-yard dung. These quantities amount to 2000 tone of dung,—a quantity which it is useless to expect, seeing that it is double what good manage ment supplies.