CiiJt ?. XL Appendix, No. 4.

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first, In flooding meadows, if water be allowed to stagnatelong on the surface, the roots of the valuable grasses are injur-ed, and the crop is on this account deficient next summer. Inflooding waste lands, our object is, to destroy the coarse anduseless herbage on the surface : with this view, therefore, the wa-ter, by being continued long on the surface, may serve this pur-pose bettdr : for, by this means, the stems and roots of theseindigenous plants may be destroyed, so as to make room for o-tliers more valuable.

Secondly, When a white scum gathers over the surface of awatered meadow, this is a signal that the water must be imme-diately removed : It shows that the putrid fermentation is al-ready begun ; and if the water were continued longer, it wouldadyance, till all the meadow grasses were destroyed. In water-ing waste lands, there is no such necessity of removing the wa-ter when this signal begins to appear. On the contrary, whenthe water begins to throw up air-bubbles, and the native plantsOn such wastes begin to change their colour, and become black,and soft, and pulpy, these are proofs that they have already be-gun to decay ; and hence an encouragement to continue the flood,till they be completely reduced.

Thirdly, The warmer the water is, and the richer, it mustsooner be removed from meadow lands, otherwise the wholeplants will be rotted, and the crop fail. In waste land, no suchprecaution is requisite ; for the object of flooding in this case, is,hot to increase the vegetation of such plants as flourish on thesurface, but to destroy them- The richer the water, and thewarmer the season is, this end may be sooner attained.

Fourthly, In watering meadows, it has been found dangerousto remove the water in time of severe frost. The reason of thisis obvious ; the water contained in the vessels of these plants, inthis case, must be frozen, and expand. By this means, the fi-bres must be burst asunder, and these plants destroyed. Inflooding Waste land of every description, the water, on this ac-count, ought to be occasionally removed in time of frost, in or-der that the noxious and useless herbage on the surface may, bythe operation of freezing, be disorganized.

In short, the object of watering meadows, and flooding wasteland, is totally different. In the former case, water is used tonourish and cherish the grasses already planted in die soil. Inthe latter, it is to destroy every indigenous plant, as they aregenerally useless. Therefore, different rules must be observedin regard to these different kinds of soil.

If these remarks be well founded, it will be no difficult mat-ter to decide the question, at what season waste lauds ought tobe flooded. It is obviously idle to contend, on the one hand,that summer is the best season, or, on the other, that winter isinore favourable ; for it is clear that, at both seasons, the oper-