manifold beneficial changes, which Deepening and Pulverizing effect in Soils, according to the ingenious researches of Davy, Thomson, Grisenthwaite, and others, who have usefully laboured to render chemical researches subservient to rural purposes. Had Tull, who flourished about a century ago, been acquainted with chemistry, as at present improved, he would not have missed that permanent fame, to which his ingenuity so well entitled him. Tull was unquestionably the first practical advocate of the power of pulverization; but he was deceived by its astonishing and various effects, without being able to perceive its limits. Hence, he was led into the erroneous belief, that pulverization could even supply the place of manures in farm management. Modern science, however, would have enabled him to discover, that, although the comminuating of Soils incredibly multiplies the fibrous roots, or mouths of plants; although it also facilitates the speedy and perfect preparation of their food, and conducts the food so prepared more regularly to the roots, yet of food itself it does not communicate the smallest supply or portion, beyond what the Soil actually possesses. As we cannot, in these times, fall into the error of Tull, let us not omit, for our present purpose, to put a due value on pulverization (which, in husbandry of late, as connected with deepening, seems to be rather undervalued), while

we endeavour, by the methods already pointed out, to add as much as possible to the vigour and food of woody plants.

Soils, then, may be most effectually improved by the planter, by altering their constituent parts, as has been above shown, either by the addition of ingredients, in which they are deficient, or by the subtraction of others, that too much abound in them; but, in ordinary cases, chiefly in the former way, by admixture with other Soils, and by the application of mineral manures. The best natural Soils are certainly those, of which the materials have been derived from different strata ; that have been minutely divided by air and water, and are intimately blended together. On this account, in improving Soils by artificial methods, the husbandman or the arboriculturist cannot steer in so safe a course, as by studying the effects of intermixture, and imitating the chemistry of na

ture.

In preparing Soils, on these principles, for the Removal of Trees, the materials cannot often lie at a distance. In this quarter of the Island, there is no man, possessing grounds of any extent, who has not the command of more than one sort of Soil, especially in the mineral districts. In the Park here, three different species are found, namely, tenacious Clay, strong Loam, and light Sand; and, fortunately also, Peat-moss in abundance,

near at hand. My practice, therefore, has been, diligently to collect and make up masses or heaps of Compost, in different parts of the grounds, adjacent to where the Trees might be wanted, and to have them always ready for use, of not less than six months old. These masses are compounded usually in the following manner : First, Quick Lime recently burnt (called in Scotland "Lime Shells") with Clayey matter, for the light land; Secondly, Mild Lime with Sandy Soil, for the aluminous; and Thirdly, Quick Lime with Peat-moss, for the loamy. To each of the two Soils first mentioned, I usually give an addition of about a third part of the Peat Compost; and, by procuring the peat in rather an advanced state of decomposition, its speedy preparation is more easily brought about.

In this way, I conceive, I have succeeded, with the least possible expense of manure and labour, in preparing materials for improving the different Soils, for the reception of the fibrous roots of Trees. The Clay compost, by means of the lime, being brought into a state of decomposition, surprisingly improves the silicious Soil, by giving it greater consistency, in the same way that the same Soil is benefited by marl, or calcareous matter. The Sand compost, in like manner, still more powerfully acts on the aluminous Soil. As all soils are meliorated by lime, that do not effervesce with

acids, and sands most remarkably, so the hard and adhesive qualities of the clay are subdued, by the action of the sand and lime united, its parts are comminuated, and the inert vegetable matter is brought into operation. The Peat compost, for similar reasons, and by means of the Lime which it contains, is well calculated to stimulate, and add vegetable matter to the loamy soil.

But the Peat compost, for general application to all soils, I have found the most extensively useful of the whole, if prepared with a third part of animal manure, or fresh farm-yard dung, according to the fermenting process, discovered by the late Lord Meadowbank. For thin gravelly soil, where a considerable quantity of carbonaceous matter is required to supply its wants, that compost, if properly made, will be found even preferable to ordinary animal manure, as containing much more carbon, and continuing its action longer on the ground. Even when prepared with quick Lime only, recently burnt and slacked, that is, hydrate of Lime, it is extremely valuable, from its loose and friable properties, and the fine state of comminution, to which it may be readily brought. Quick lime, when it becomes mild, operates in the same way as chalk; but, in the act of becoming mild, it has the power of preparing soluble out of insoluble matter. Hence its great effect on peat, and on all soils containing

an excess of vegetable insoluble matter. But for Peat-compost to operate fully in preparing the soil for the fibrous roots of plants, it should be mixed in the ground, for at least a twelvemonth before the Trees are removed, so that, on opening the pits for the second time, it shall have nearly disappeared, in consequence of its complete and perfect incorporation with the soil.

There is one circumstance, which deserves particular attention, in preparing this valuable compost. It is observable in the southern, as well as in the northern division of the Island, that Peatmoss is found of very different qualities, and has frequently some portion of Iron combined with it, united with Sulphuric Acid. This is a mixture, which, in excess, is pernicious to vegetation, and to the growth of woody plants. It, therefore, becomes necessary to destroy or neutralize it, by admixture with other substances. The respectable Judge above mentioned says, that all his peat at Meadowbank was so contaminated. Some part of the peat, at this place, is unfortunately of the same species, and many of my crops, as well as Trees, were injured by it, before the cause was discovered. When the Peat is taken from the pit, and laid out to dry in the heap, the sulphate of iron is easily distinguished, by an efflorescence of small white crystals of an astringent taste, appearing on the surface, and also a strong sulphurous smell,