clays; as the ground cannot be entirely removed, and some part must even remain untouched. But, in the rich friable soils of Tuscany, the smaller plough is a most useful instrument; for, in that country, the least effort is sufficient to divide and pulverize the land: we have been induced to communicate the figure above-mentioned, chiefly on account of its simplicity, and as there are similar soils in the Southern parts of Britain; where, we conceive, the Italian ploughs may be advantageously employed.—Lastly, the deep furrows, that remain in the ground after it has been ploughed, present a greater surface to the action of the sun and air; a circumstance materially conducing to its improvement.
We have here given an extensive view of the subject, on account of its national importance.—Justice, however, impels us to mention another contrivance, for ascertaining the force necessary in the draught of various ploughs. It was presented to the public by Mr. More, the late ingenious Secretary to the Society for the Encouragement of Arts, &c.: it consists of a spring coiled within a cylindrical case, which is furnished with a dial-plate numbered in a manner similar to that of a clock; and which is so constructed, that the hand moves in consequence of the motion of the spring, and points to the numbers according to the force exerted: thus, if the draught be equal to one cwt. over a pulley, the hand will be directed towards figure 1; when the draught equals two cwt. it points to figure 2; and continues to increase, or diminish, its progress in proportion to the exertions made.
Various experiments were conducted under the inspection of the Society, when the accuracy of this machine was fully evinced; a detailed account of which is inserted in the first volume of Annals of Agriculture: where the different results are minutely recorded.
PLOUGHING, in rural economy, denotes the stirring and turning over of land with the plough.
This is one of the most essential operations in the culture of the earth, and requires to be performed with the greatest care. Whatever, therefore, may be the design of the farmer, or the destination of the ground, thus moved, it ought never to be ploughed in a wet state; because the soil cannot be improved by such labour. Farther, the plough ought to be carried to a considerable depth into the soil; and, if one turning be not sufficient, it will be advisable to pass another plough over the same furrow, so that the land may be effectually stirred; when, being thus exposed to the air, its fertilizing properties will not only be considerably augmented, but all perennial weeds will be completely eradicated.—Deep ploughing, however, is unnecessary for land that has been recently manured with lime or marle; but, on exhausted soils, it is uncommonly beneficial, and has, therefore, been generally recommended by the most skilful husbandmen.
Ploughing increases the food of plants; as it opens the soil for the reception of vegetable aliment from the air; and, the surface being consequently enlarged, a greater portion of land is thus exposed to its influence. Farther, by breaking up the ground, if it be too solid, and rendering it firm, in case it be too light, this operation greatly
