144 TECHNOLOGY. 
(jig. 39), and when sufficiently dry it is stored in stacks or barns. These 
stacks are so formed as to shed the rain, and are thatched with long straw, the 
more effectually to exclude the rain. PU. 30, jigs. 25 and 26, are common 
forms, the former as put up in Germany, the latter in England. Before the 
general introduction of threshing machines, the grain was beaten out upon a 
threshing-floor, generally formed in the barn itself. The threshing-floor was 
prepared by first covering it with stiff clay, which was moistened, trodden, and 
beaten; when dry it was wet with bullocks’ blood, and after further beat- 
ings, suffered to harden. PJ. 30, jig. 32, shows an English grain-barn and. 
threshing-floor beneath the same roof. /%g. 33, another arrangement of 
the same with corn-loft, potatoe-bin, and tool-house added. Movable grain- 
barns are sometimes made use of, which are brought up to the side of the stack 
which is to be threshed (pl. 30, fig. 84). In most parts of Europe grain is 
still threshed by hand with the flail ; in the United States threshing-machines 
are in almost general use for the purpose, and usually consist of a cylinder 
of wood or iron, studded with teeth, which revolves rapidly within a con- 
cave also filled with teeth, so arranged that the rows of teeth on the cylinder 
fall into the spaces between the teeth upon the concave; the grain being fed 
into this machine is carried round by the cylinder and violently beaten 
between its teeth and those of the concave, and the grain thus threshed falls 
out at one end of the machine, while the straw is carried out at the other end 
by the centrifugal action of the cylinder and the draught which it occasions. 
Where the grain is threshed by hand it is much mixed with chaff and the 
dust of the threshing-floor ; to separate it from these it is passed through the 
winnowing machine or fan (pl. 29, figs. 87 and 38). The grain is put into 
the hopper, /, from which it is delivered gradually upon a vibrating sieve 
which permits the grain, but not the larger pieces of straw, to pass through ; 
it then descends upon the inclined board, 4, to the back of the machine, 
whilst the dust and lighter particles of chaff are blown out at the other end 
by the revolving blower or fan, d, e, f, g. 
In some parts of Europe grain intended for grinding is first coarsely 
broken up on a mill seen in pl. 29, jig. 40, in which the grain is crushed 
between revolving rollers. 
When the straw, after the grain is threshed out, is used for feeding, it is 
first cut into short lengths, the better to be mixed with the grain or other 
food used with it. This is performed upon the straw-cutter. Upon small 
farms this machine consists of a trough three to four feet in length, 
through which the straw is fed beneath the edge of a knife worked by 
hand. On larger establishments more effective machines are in use; in 
one represented in pl. 29, jig. 41, the knives are secured to the arms of a fly- 
wheel, which is made to revolve rapidly and thus cut the straw as it is fed 
from the end of the trough. 
Before we proceed further it may be well to say something upon the 
preservation of the various products of the farm. 
In some parts of Europe many kinds of grain are kiln-dried before being 
threshed. Pl. 30, figs. 40 and 41, show an arrangement used for this pur- 
pose. The same building contains the threshing-floor, the stove, and the 
724 
