MILLS. 73 
driving-wheels, t; jig. 15, box in which the spindle of the main driving- 
shaft rests. The same letters indicate corresponding parts in all the figures. 
The base, A, carries the pedestal, B, and the columns, c, which support 
the flooring, p, carrying the ring 5, which supports the different bed-stones. 
Upon the bed, p, are the triangular frames, r, regulated by set-screws, and 
upon which the bed-stones, F’, rest, while the runner-stones, F’, hang upon 
the top of the upright shafts, c. Within the bed-stone is the mill-bush, u, 
through which the shaft, @, passes. In the eye of the runner-stone is the 
rind, 7, and the tube, 7, which feeds the grain to the stones, from the recep- 
tacles, v, to which it is brought by the tubes, s, from the room above. The 
runner, F’, is raised and lowered by a suitable arrangement. The shaft, a, 
which carries it, is supported in a box, 7’’, on the top of the hollow column, 
J, within which is a rod, 1, on which the above named box rests; this rod 
rests upon a lever, x, which is raised or lowered by a rod, L, passing up 
through one of the columns, c (jig. 4), by which means the box, 7” and 
with it the shaft which carries the runner-stone, is raised and lowered. 
The whole system is driven by the main-wheel, m, upon the horizontal 
shaft, n, which is in gear with the driving power (jig. 7). Upon the other 
end of this shaft is a bevel wheel, 0, which engages with another wheel, p, 
upon the upright shaft, a, carrying the large cog-wheel, s, which drives the 
smaller wheels, Tt, upon the shafts of the mill-stones. The stones are inclosed 
in cases, u, which prevent the waste of the flour; from these cases the flour 
is delivered into a circular trough x (jig. 8), in which are made to revolve 
the arms or scrapers, v (jig. 2), which sweep the flour round into another 
trough, through which it is carried by the screw-formed conveyor, z, to the 
elevators, z’, seen at the right hand upper corner of the machine in jig. 3. 
Upon the main shaft is a small pulley, c’, from which a band passes to the 
governor, 4’, which regulates the velocity of the steam-engine, and conse- 
quently of all the machinery driven by it. 
In all well arranged mills the grain, before being ground, is freed from 
foreign substances; this is sometimes accomplisned by passing the grain 
through a cylindrical riddle, furnished with screw-formed divisions on the 
inside, so that as the riddle revolves the grain passes over a great extent of 
surface, and is measurably freed from dust and other extraneous substances. 
Very perfect machines have been invented and put into use for the purpose 
of cleaning grain, which is accomplished in most of them by subjecting it 
first to friction and then to a current of air which carries off the impurities. 
By one process recently invented in the United States the grain is not only 
freed from the impurities which it may contain, but entirely deprived of its 
hull or skin. This process is briefly as follows: the grain is moistened for 
a few seconds in either steam or water, and is then passed through rubbers, 
which take off the outer skin entirely, leaving the useful portion of the 
grain clean and white; from the rubbers it passes through a kiln, in which 
it is again dried, and then it is run through a fan which blows off all the 
impurities with the skin, leaving the grain ready for the mill; it is then 
ground, and may be packed at once in barrels, as it requires no bolting or 
any further preparation. The seeds of garlic and other weeds, which have 
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