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The grain is next allowed to descend by a shoot or trough (the descent being regulated by traps) into a large hopper, resting on the platform of a weighing machine; its weight is then registered, and afterwards, by drawing a trap in the bottom of the hopper, the grain is allowed to descend by another shoot to a lower story.

It is next raised by an elevator to the highest story of the mill, where it is cleaned by passing through three different machines. The greatest care and attention is bestowed on this process, in order to insure the perfect cleansing of the grain preparatory to its being ground.

The grain is then conducted to the stock-hoppers, which feed eight pairs of grinding-stones.

A short length of the feeding-pipe of each pair is made of glass, through which the grain, as it descends, can be seen. The stones are 4 feet in diameter, and make 232 revolutions per minute.

The meal, when ground, is conveyed by means of a spiral conveyor to the cooling chamber, where a rake, revolving horizontally, is substituted for the old "hopper-boys." The meal is raked from the circumference to the centre, where it falls through a hole, and is taken to the bolting machine; it is there sifted, and separated into different qualities of flour. It is then