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roller whose cutting-edges look downward is 
fixed a pinion of eight teeth; on that of the 
other roller is fixed a wheel of twenty teeth, 
driven by the pinion; the cutting-edges of the 
pinion-roller move in a descending direction, and 
with 24 times more speed than those of the other 
roller; and the grain, in passing between the two 
sets of cutting-edges is cut as with a series of 
scissors, and, in consequence of the shallowness 
of the grooves, is held so close to them that it 
cannot escape their cutting action. A fly-wheel 
is hung upon the axle of the first roller ; and as 
| a feeding-roller, driven by a motion from the 
former, is placed above and between the two 
cutting-rollers, it is usually of the same diameter 
as these, and formed with six or eight longitu- 
dinal semicylindrical channels, three-fourths of 
an inch wide, and three-eighths of an inch deep ; 
and these receive the grain from the bottom of 
a hopper placed over the feeding-roller, and de- 
liver it in due succession to the cutting-rollers. 
Moveable bushes are constructed to contain one 
of the cutting-rollers ; and these can be so shift- 
ed and adjusted by screws as to suit the kinds 
_and quality of the grain, and the degree of fine- 
| ness to which it is to be reduced. 
When grain is damp, it clogs grooved rollers, 
and cannot be efficiently cleared away from the 
grooves; but it possesses less adherence to plain 
rollers, and can easily be cleared away from them 
by means of permanent scrapers. A machine 
with plain rollers has been supposed to require 
more labour than one with grooved rollers, and 
hence has by some persons been thought less use- 
ful; but besides being of superior efficiency in 
performing its office, it may, if properly con- 
| structed, be really worked with at least equal 
| ease. 
A good machine of this description may, 
with moderate labour, be so worked by one man 
as to prepare a boll of oats in an hour and a half. 
The standard of a well-constructed one consists 
| of two frames of cast-iron, with bars of 23 inches 
in breadth and five-eighths of an inch in thick- 
ness, and measuring all over 26 inches at bottom 
and 19 inches at top. The frames are put to- 
gether with malleable iron stretchers, and se- 
cured with screw-nuts; and, when bolted to- 
gether, they have a width of 17 inches at bottom 
and 8 inches at top. The side-frames have at 
bottom projecting palms, for increasing the base ; 
and, at top, small palms or snugs for attaching 
the roller-case to the standard. “The roller-case 
consists of two cheek-plates, into which the en- 
tire bushes are inserted for the axles of the rol- 
lers; the cheeks are held together by four bolts, 
which also secure the ends of the case ; a pinion 
of eight teeth is fixed upon the axle of the feed- 
ing roller, and gives motion first to the wheel of 
24 teeth, set upon the axle of one of the bruising- 
rollers, which may be called the driver. The dia- 
meter and position of the two bruising-rollers are 
each seven inches in diameter, and seven inches 
in length, while the feeding-roller is only four 
BRUISING CORN. 
inches in diameter. On the opposite ends of the 
axles of the bruising-rollers, each roller is mounted | 
with a wheel of 16 teeth, working into each 
other, thus making both rollers move at the same: 
velocity, while the feeding-roller moves three 
times faster. The handle or winch is fitted to 
the pinion or feeding-roller, the fly-wheel being 
mounted on the opposite end. The second or 
driven roller is supported on moveable bushes, 
and can be adjusted by the pinching-screws to 
produce any degree of fineness required. For the 
regulation of the feed, a plate is bolted on, and 
forms the top of the roller-case ; it is formed with 
a prismatic channel equal in length to the roller, 
2% inches wide at top, and at bottom opens into 
a slit # inch wide, parallel to the rollers. Two 
moveable shutters are adapted to the upper part 
of this opening, and are capable of being set at any 
distance, according to the degree of feed required ; 
/ which can be determined by the operator after a 
few turns of the handle. The hopper, made of 
deal, is secured in a temporary manner by means 
of two hooks and eyes to the top of the machine; 
and the spout, fixed to the standard, carries the 
bruised grain from the rollers, and delivers it 
into a measure or basket.” 
The bruising machines which are driven by 
water, steam, or horse-power, are so simple in 
construction and in mode of working as not to 
require any lengthened description. Almost all 
consist of plain rollers or cylinders of cast-iron, 
accurately turned in the lathe, and varying 
from 12 to 24 inches in length, and from 6 to | 
12 inches in diameter. A few are so awkwardly 
and uneconomically constructed as to have a 
length of only about 6 inches, and yet a diameter | 
of two, three, or even four feet. All perform 
their work simply by their rollers being kept in 
rapid motion, and by the corn being supplied 
from a hopper, and bruised by passing between 
the rollers. 
they are moved by a sufficient power, may aver- 
age about 300 feet per minute; and a pair of 
rollers, when worked by four horses, will bruise 
about 120 bushels per hour. 
BRONZE. An alloy of copper, with tin, zinc, 
&c. Two kinds may be distinguished, Antique 
and Modern bronze, the former consisting of cop- 
per and tin, the latter containing zinc, in addi- 
tion to copper and tin, or sometimes containing 
no tin. Modern bronze may therefore be brass 
with an excess of copper. The principal objects 
of bronze are cannon, bells, statues, and medals, 
the principles of manufacture in all being similar. 
Taking bronze in a more limited sense, as con- 
sisting of copper and tin, it has the following 
general properties. Itis harder and more fusible 
than copper ; it is slightly malleable, when it con- 
tains over 85 per cent. copper, and becomes more 
so by tempering ; it oxidizes very slowly in moist 
air. Its density is greater than the mean density 
of its constituents. The addition of about 1 per 
cent. of iron, or rather of common tinned iron 
The velocity of the machines, when | 
