Chap. 11.]

CONSTRUCTION OF MACHINES.

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take an equal quantity; they are nailed to the strap withlong, small nails, with broad heads, which are inside thestrap; the meal should always be let into them above thecentre of the pulley, or at the top of it, to prevent itschoking, which it is apt to do, if let in low. The mo-tion should be slow for meal, but may be more lively forwheat.

Directions for using a Hopper-boy .

1. When the meal elevator is set in motion to elevatethe meal, the hopper-boy must be set in motion also, tospread and cool it; and as soon as the circle is full, thebolts may be started; the grinding and bolting may like-wise be carried on regularly together; which is the bestway of working.

2. But if you do not choose to bolt as you grind, turnup the feeding sweepers and let the hopper-boy spreadand cool the meal, and rise over it; and when you beginto bolt, turn them down again.

3. If you choose to keep the warm meal separate fromthe cool, shovel about 18 inches of the outside of the cir-cle, in towards the centre, and turn the end flights, todrive the meal outwards; it will then spread the warmmeal outwards, and gather the cool meal into the boltinghopper. As soon as the ring is full with warm meal,rake it out of the reach of the hopper-boy, and let it fillagain.

4. To mix tail-flour or bran, &c., with a quantity ofmeal that is under the hopper-boy, make a hole for it inthe meal quite to the floor, and put it in; and the hop-per-boy will mix it regularly with the whole.

5. If it do not keep the hopper full, turn the feed-ing sweeper a little lower, and throw a little meal on thetop of the arm, to make it sink deeper into the meal.If the spreading sweepers discharge their loads too soon,and do not trail the meal all around the circle, turn thema little lower; if they do not discharge, but keep too full,raise them a little.