Of Collinri4 The use of manure in the shape of compost, or ingre dients of various ies, mixed together in certain propo, tions, has long been a favourite practice with many [trim:1's ; though it is only in particular situations that the practice can be extensively or profitably exe med. T:le ingredients used in these composts are c hi.• rth at lime ; sometimes dung, when: the earth ; hut lime may be regarded as the main agent of to process, acting as a stimulus for bringing the powers of the Ii. ap into action. Lime, in this , may be con '1,1,.:rod as a kind of yeast, operating a heap of earth as yea•lt does upon flour or meal. It is 01)1,1611s, there. fore, that a sufficient quantity is given, the heap may remain unfermented ; in which case little benefit will be derived from it as a manure.
The best kind of earth for compost is that of the allu vial sort, winch is always of a rich greasy substance, often mixed with marl, and in every respect well calcu lated to enrich and invigorate barren soils, especially if they are of a light and open texture. Old yards, deep head-lands, and scourings of ditches, offer themselves also as the basis of compost middens; hut it is proper to summer-fallow them befiire hand, so that they may be entirely free of weeds. When the lime is mixed with the soil of these middens, repeated turnings are neces sary, that the whole may he suitably fermented ; and some care is required to apply the fermented mass at a proper time to the field on which it is to be used.
The formation and conveyance of compost being ex pensive, it becomes an important object to save labour in the previous steps of preparation, and in the concluding one of applying it to the soil. The first part of the ob ject is gained by using horse instead of manual labour, when the lime is incorporated with the earth, and when the after turnings are bestowed; and the other is lessen ed considerably when the compost is laid on a field ad joining the one where it is prepared.
A few words may be necessary with respect to the quantity of lime required to produce a suitable fermen tation, though here we can at best but speak at random, because the proper quantity falls to be regulated by the nature of the earth which is meant to be used as the ba sis of the future compost. As the quantity of the com post to be aft rwards applied to the soil must, however, be ascertained by its quality, and as sixty cubic yards of alluvial compost may be viewed as containing the same portion of nutritive substance, as one hundred yards of headlands and ditch scourings, we shall assume eighty yards as a medium dose Ion a Scotch acre of ground, and from this datum endeavour to fix the quantity of lime that is required. From trials that we have frequently made, it appears, that two bushels of lime shells, Win chester measure, will sufficiently ferment a cubic yard of earth of a medium quality ; therefore, that forty bolls of lime-shells, wheat measure, or twenty-six and two-thirds barley measure, are requind to ferment compost for an acre of ground, where the basis consists of ordinary ma terials. This goes upon the supposition that an admix ture is regularly conducted, and that eighty cubic yards of the compost is sufficient to impregnate or enrich the field on which it is to be applied.
The benefit of such a compost in nourishing soils is even greater than what is gained by dressnig them with dung ; though it is to be regretted, that it rarely happens, where such soils are predominant, that materials such as we have recommended can be procured in any quantity. Another sort of compost has therefore been recently tried, and with tolerable success. Should a repetition prove equally successful, or the first trials be fullv con firmed by the experience of others, agriculture will be benefited in a quarter where the art was hitherto consi dered as naturally incapable of improvement.
On this subject, lord Nleadowbank, o;le of our su preme judges, has lately favoured the public with a small pamphlet, containing directions for making compost dunghills of peat-moss. We therefore use the freedom of borrowing his lordship's directions, trusting that there by the public good may in some measure be promoted.
"Let the peat-moss, of which compost is to be formed, he thrown out of the pit Ihr sonic weeks or months, in order to lose its redundant moisture. By this means, it is rendered the lighter to carry, and less com pact and weighty, when made up with fresh dung for fermentation ; and, accordingly, less dung is required for the purpose, than if the preparation is wade with peat taken recently from the pit. The peat taken from near the surface, or at a considerable depth, answers equally well.
" Take the peat-moss to a dry spot, COHN enicnt for constructing a dunghill to serve the lield to be ma !lured. Lay the cart-loads of it in two rows, and of the dung, in a row betwixt them. The dung thus lies nearly on an area of the future compost dunghill, and the rows of peat should be near enough each other, that workmen, in making up the compost, may be able to throw them together by the spade. In making up, let the workmen begin at one end ; and at the extremity of the row of dung, (which should not extend quite so far at that end as the rows of plats on each side of it do,) let them lay a bottom of peat, six inches deep and fifteen legit wide, if the grounds admit of it ; then throw forward, and lay on, about ten inches of dung above the bottom of peat ; then add from the side rows about six incites of peat ; then four or five of dung, and then six 11/01'e of peat ; then another thin layer of dung ; and then cover it over with peat at the end where it was begun, at the two sides, and above. The compost should not be raised above four feet, or four feet and a half high ; other wise, it is apt to press too heavily on the under parts, and check the fermentation. When a beginning is thus made, the workmen will proceed working backwards, and adding to the column of compost, as they arc fur nished with the three rows of materials directed to be laid down for them. They must take care not to tread on the compost, or render it too compact ; and, of con sequence, in proportion as the peat is wet, it should he made up in lumps, and not much broken.