1803;] Improvement of the Drill Plough. 9

enlarged, by slitting the tin three cighths of an inch towards A, on each s1ide of the hole; and then that part of the tin, included between these two slits, which will be half an inch wide, and three eighths of an inch lengthways, in respect to

the cylinder, is not to be cut out; but to be bent down into the

excavations of the wooden cylinder beneath, s0 as to lie against the end of the excavation, which is next to A; but these projecting bits of tin before they are bent down intóô the excavations of the. wooden cylinder, must be filed a little less at the projecting end, which. is to be bent down, than: at the other end; as the excavations of the wooden cylinder are to be rather narrower at the bottom than at top, and these pieces of tin when bent down must exactly fit them.—Lastly, when all these holes through the tin cy- linder are thus enlarged, and the bits of tin filed rather narrower at theeprojecting ends, and then bent down into the excavations of the wooden cylinder, the other end of the tim cylinder with its square socket may be soldered on. And now when the end of the tin cylinder, at A, is pressed forwards upon the wooden cylinder towards B, by turning the screw at x, above, described; every excavation of the wooden cylinder will be gradually lessened, and finally quité closed; by which easy means they may be. adapted to re- ceive and deliver sceds of any sìize, from horse beans and peas, to wheat, barley, and turnip seed, with the greatest aGcuracy, 80 as to s0w four, five, or s1x pecks on an acre, or more or less, as the agricultor pleases, by only turning the screw a few revolutions one way or the other. Observations. 1. In the construction of the tin and wooden cylinders beneath the seed box, another small im- provement may be necessary in sowing very small seeds, which 1s thus:—as the screw of the end, or À; is turned s0 as to contract all the excavations of the woooden cylinder— the surface of the wooden cylinder, for one inch from the end of each excavation, towards the end B, Fig. 4. will becóme bare without being covered by the tin cylinder; and on these bare parts of the wooden cylinder, which will be one inch long and half an inch wide, some small seeds may chance to stick and evade the brushes, which should prevent them from passing as the cylinders revolve—to pre- vent this, when the wooden cylinder 1s s0 placed within the tin cylinder, that all the holes are quite open, let a picce of the lin cylinder about an inch and an half long, and half an inch wide be cut out from the extremity of each hole next to the end B; and let this piece of tin cylinder thus cut out, be fixed by a few sprigs on the wooden cylinder, ex- actly in the same place which it covered before it was cut

¿out of the tin one; by which contrivance, when the tin