IN SCOTLAND.

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roller may answer the purpose, yet in others a heavy one isnecessary. The roller, therefore, ought to be so constructed,that its weight can easily be increased or diminished at plea-sure. If the roller be long, and of a large diameter, then itought to have the greater weight in proportion; for the largerthe roller, the more of its surface will touch the ground atonce, which consequently must lessen its impression on theland when rolling. This is a good objection to the woodenrollers just mentioned. Stone or cast-iron are preferable.It is therefore of importance that the weight of the roller bein proportion to the extent of surface on which it rests, andthe nature of the land on which it is rolling.

In the opinion of intelligent farmers, the roller should notbe less than twelve, nor more than thirty inches in diameter;because if the roller is too small, it is apt to push the hardclods before it; and if too large, it has then little effect inbreaking the clods. The roller generally made use of is fromfive to seven feet in length; this great length, however, is notonly very severe on the cattle, when turning at the end of a fieldor ridge, but there is also danger of tearing up part of the crop,because, in turning short, tlio long roller does not move roundits axis, but is dragged along. To prevent these great incon-veniences, it would seem preferable to have two rollers, each a-bout three feet in length, and both placed into one frame, so asto roll clear of one another. These two short rollers would serveequally well as a long one for breaking the clod, and smooth-ing the surface of the land, when rolling straight forward, andbe more suitable for particular purposes, such as corn crops,or sown grass, as, in turning short, they neither tear up thetender soil, nor injure the young plants. Each of them inturning moves round its own axis, the one rolling forwards,whilst the other is rolling backwards. By this means thesurface of the land is not broken, and the young plants areleft uninjured. Besides, the labour in turning is much lesssevere on the cattle.