Chap. 10.] APPLICATION OP THE MACHINES.

211

ARTICLE 90.

OF ELEVATING GRAIN FROM SHIPS.

If the grain come to the mill by ships, No. 35, andrequire to be measured at the mill, then a conveyer, 35—4, may be set in motion by the great cog-wheel, andmay be under or above the lower floor, as may best suitthe height of the floor above high water. This conveyermust have a joint, as 36, in the middle, to give the endthat lies on the side of the ship, liberty to rise and lowerwith the tide. The wheat, as measured, is poured intothe hopper at 35, and is conveyed into the elevator at 4;which conveyer will so rub the grain as to answer theend of rubbing stones. And, in order to blow away thedust, when rubbed off, before it enters the elevator, partof the wind made by the fan 13, may be brought down bya spout, 13—36, and, when it enters the case of the con-veyer, it will pass each way, and blow out the dust at 37and 4.

In some instances, a short elevator may be used, withthe centre of the upper pulley, 38, fixed immoveably,the other end resting on the deck, but so much aslant asto give the vessel liberty to raise and lower, the elevatorwill then slide a little on the deck. The case of thelower strap of this elevator must be considerably crooked,to prevent the points of the bucket from wearing by rub-bing in their descent. The wheat, as measured, ispoured into a hopper, which lets it in at the bottom ofthe pulley.

But if the grain is not to be measured at the mill, thenfix the elevator 35—39, to take it out of the hold, andelevate it through any conveniently situated door. Theupper pulley is fixed in a gate that plays up and downin circular rabbets, to raise and lower to suit the tide anddepth of the hold, and to reach the w heat. 40 is a draftof the gate, and manner of hanging the elevator in it.(See particular description thereof, in the latter part ofArticle 95.)

This gate is hung by a stout rope, passing over a strong