furface had extended in the direction of the doted line a d.

But, fuppofing that the ftratum of clay, after approaching to the furface at A, continued to keep at a little depth below ground; and that the foil which lay above. it was of a fandy or fpungy nature, fo as to allow the water to penetrate it easily. In that cafe, even fuppofing the quantity of water that flowed from D to C was but very inconfiderable, inftead of rifing out at the fpring A, it would flow forward along the furface of the clay among the porous earth that forms the foil, fo as to keep it constantly drenched with water, and, of consequence, render it of very little value.

Wetnefs, arifing from this caufe, is ufually of much greater extent than the former; and, as it admits of an easy cure, it ought not to be one moment delayed. For a ditch of a very moderate depth opened at A, and carried through a part of the ftratum of clay,

(as

1

(as reprefented by the doted lines A, k, f) would intercept and carry off the whole of the water, and render the field as dry as could be defired. It is, therefore, of very great confequence to the farmer, accurately to diftinguish between these two cafes, so nearly allied to each other in appearance; and, as this can be easiest done by boring, every one who has much ground of this kind ought to provide himself with a fet of boring-irons, which he will likewife find ufe for on other occafions.

I might here enumerate a great variety of cafes which might be reduced to the fame head with the foregoing: But, as any attentive reader may, after what has been faid, be able eafily to diftinguish these, I shall only in general obferve, That every foil of a foft and porous texture, that lies upon a bed of hard clay, whatever its fituation in other respects may be, will in some measure be fubjected to this disease. And, if it is

upon

upon a declivity of any confiderable length, the undermoft parts of the field will be much damaged by it, unless ditches are thrown up across the declivity, at proper diftances from one another, to intercept the water in its 'descent.

It may not likewife be improper here to remark, that, in cafes of this nature, unless where the foil is of a very great depth, the malady will always be encreased, by raising the ridges to a confiderable height; as will appear evident by examining Fig. 22d,in which the line A B reprefents the furface of a field of this nature, and CD the surface of the bed of clay. Now, if this field were raised into high ridges, as at F, F, F, so as that the furrows E, E, E, defcended below the furface of the clay, it is plain, that all the water that should fink through the middle of the ridge, would run along the surface of the clay, till it came to the fides of the ridge L, L, L, L, L, L, which would

Ꮓ

would thus be kept continually foaked with water. Whereas, if the ground had been kept level, as in the part of the field from G to H, with open furrows H, at moderate diftances from one another, the water would immediately fink to the clay, and be carried off by the furrows, fo as to damage the foil far less than when the ridges are high.

1

If the foil is fo thin that the plough can always touch the clay, the ridges ought to be made narrow and quite flat, as from G to H: But, if there is a little greater depth of foil, then it ought to be raised into ridges of a moderate height, as from H to K, fo as to allow the bottom of the furrow to reach the clay. But neither is this neceflary where the foil is of any confiderable depth.

I have seen some induftrious farmers, who having ground in this fituation, have been at the very great expence of making a covered drain in each furrow. But, had they rightly understood the nature of the disease,

they

they never would have thought of applying fuch a remedy; as muft appear evident at firft fight to those who examine the figure. The fuccefs was what might be expected from fuch a foolish undertaking.

These observations, it is hoped, will fuffice as to the manner of treating wet, fandy, or porous foils. I now proceed to take notice of fuch as are of a stiff clayey nature, which are often very different in appearance, and require a different treatment from these.

Suppofe that (as in Fig. 23d,) the ftratum of fand or gravel D C should be discontinued, as at E, and that the ftratum above it fhould be of a coherent clayey nature. In this cafe, the water that flowed towards E, being there pent in on every fide, and being accumulated there in great quantities, it must at length force a paffage for itself in fome way; and preffing ftrongly upon the upper furface, if any one part is weaker than the reft, it there would burft forth and form a

fpring,