The Evolution of Agricultural Implemente. 241 
An Act of Parliament, passed in 1878, requires that every 
steam threshing-machine shall be provided with such a guard 
as will effectually prevent the man engaged in feeding it from 
being drawn, or falling accidentally, into the drum . Previously to 
this, however, or in 1871, Mr. Wilder had patented a safety feed 
which, especially since the passing of the Act in question, has 
been adopted by several eminent makers. Wilder’s guard is, in 
effect, a small straw-shaker delivering sheaves to the drum and 
fed by an attendant, who himself stands in a place of safety. 
Drum-guards are now very numerous, and the subjects of 
many patents, but they all depend on one of two principles. On 
the one hand, it is assumed that the feeder is quite safe so long 
as he is in his box, and that only when he is out of it can he 
possibly fall into the drum. The guard, in this case, consists of 
a cover which keeps the mouth of the machine permanently 
closed until the feeder gets into place, when his weight, de- 
pressing the bottom of the feed-box, gives movement to levers 
which open the drum-guard. In the other case, matters are so 
arranged that upon any undue pressure coming, either on the 
feeding board, or on a curved hood which half covers the mouth, 
the latter is closed by a self-acting shutter. 
Winnowing-machines.— Although, the fan was used as a means 
of separating the chaff from the wheat by many peoples of an- 
tiquity, it is scarcely a century ago since the winnowing-machine 
was first patented in England, Cooch, of Harlesden, being the 
inventor, and the date of his patent June, 1800. It is an in- 
teresting and somewhat remarkable fact that one of Gooch’s first 
machines, which had been in practical use at that time for seventy- 
nine years, was on view at the Royal Agricultural Society’s Show 
at Kilburn in 1879, among a number of ancient implements 
brought together in the comparative museum which formed a 
part of the exhibition. 
The finishing thresher has atrophied the winnower proper, 
which latter machine remains pretty much the same simple com- 
bination of riddles and fan-blast as in Gooch’s day, while the 
former has absorbed into itself many of the important improve- 
ments in dressing and cleaning corn made during recent years 
in connection with milling. 
In 1858, Mr. Ghilds first introduced from America an ex- 
haust fan designed to take the place of a blower for cleaning 
grain in conjunction with riddles, and this successful innovation, 
subsequently improved by his patent of 1864, came rapidly into 
general use. Underhill, in 1859, first applied an exhaust fan 
to the threshing-machine, and Glayton and Shuttleworth, having 
acquired his patents, soon used the exhaust both for the bagging 
