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CONSTRUCTION OF MACHINES.

[Chap. 11.

lower ends of these boards are made two inches narrower,as far as the pulley-case extends; the side-board of thepulley is nailed, or rather screwed, to them, with woodenscrews. The rest of the case boards join to the top ofthe pulley-case, both being of one width. The block,which the gudgeons of this pulley run in, is screwed fastto the outside of the case boards; the gudgeons do notpass quite through, but reach to the bottom of the hole,which keeps the pulley in its place.

The top and bottom boards, and, also, the side-boardsof the strap-cases, are extended past the upper pulley,and the side-boards of the pulley-case are screwed tothem; but this leaves a vacancy between the top of theside-boards of the strap-cases, and shoulders for the buck-ets to catch against, and this vacancy is to be filled upby a short board, guiding the buckets safely over the up-per pulley. The case must be as close to the points ofthe buckets, where they empty, as is safe, that as littleas possible may fall down again. There is to be a longhole cut into the case at B, for the wheat to fall out at,and a short spout guiding it into the crane spout. Thetop of the short spout next B, should be loosely fastenedin with a button, that it may be taken off, to examine ifthe buckets empty well, &c. Some neat workmen havea much better way of casing the pulleys, which is noteasily described; what I have described is the cheapest,and answers very well.

The wheat should be let in at the bottom, to meet thebuckets; and a gate should shut as near to the point ofthem as possible, as at A, fig. 1, Plate VI. Then, ifthe gate be drawn sufficiently to fill the buckets, and theelevator be stopped, the wheat will stop running in, andthe elevator will be free to start again; but if it had beenlet in any distance up, then, when the elevator stopped,it would fill from the gate to the bottom of the pulley,and the elevator could not start again. If it be, in anycase, let in at a greater distance up, the gate should beso fixed that it cannot be drawn so far as to let in thewheat faster than the buckets can take it, else the casewill fill and stop the buckets. If it be let in faster at the