MECHANICS, 
(3s 8 
MACHINES for. VARIOUS USEFUL PURPOSES. 
A Hand Corn-mill. 
As a well-conftrufited, yet cheap, family corn-mill, can¬ 
not but be highly ufeful in many parts of the country, 
we (hall begin our lift of ufeful machines with a defcrip- 
tion of the family-mill and bolter of Mr. T. Ruftall, of 
Purbrook-beath, near Portfmouth, who, in the year 1800, 
received ,a premium of forty guineas from the Society of 
Arts for bis invention. 
A, fig. 28. is the handle of the mill ; B, one of the 
mill-Hones, which is about 30 inches in diameter, and 5 
inches in thicknefs, moving with its axis C ; D, is the 
other mill-ftone, which, when in ufe, is ftationary ; but 
which may be placed near to, or at a diftance from, the 
moveable (tone B, by means of three fcrews paffing through 
the wooden block E, that fupports one end of the axis C, 
after it has been put through a hole or perforation in the 
bedflone. The grain likewife paffes through this perfo¬ 
ration from the hopper, F, into the mill. F reprefents 
the hopper, which is agitated by two iron pins on the axis 
C, that alternately raife the veffel containing the grain, 
which again finks by its own weight. In confequ'ence of 
this motion, the corn is conveyed through a fpout that 
paffes from fuch hopper into the centre of the mill be¬ 
hind, and through the bedftone D. G, a paddle, regu¬ 
lating the quantity of corn to be delivered to the mill, 
and, by raifing or lowering which, a larger or fmaller pro¬ 
portion of grain may be furniflied. H, the receptacle for 
the flour, into which it falls from the mill-flones, when 
ground. I reprefents one of the two wooden fupporters 
on which the bedflone, D, refts, Thefe are fere wed to 
the block E, and likewife snortifed into the lower frame¬ 
work of the mill at K, which is connected by means of 
the pins or wedges L, L, L, that admit the whole mill to 
be eafily taken to pieces. M is a fly-wheel, placed at 
the furtheft extremity of the axis C, and on which ano¬ 
ther handle may be occafionally fixed. N, a fmall rail, 
ferving to keep the hopper in its place; the furthefi part 
of fuch hopper relfing on a fmall pin, which admits of 
fufticient motion for that veffel, to (hake forward the corn. 
O, a fpur-rail, for ftrengthening the frame-work of the 
mill. P, the front upright, that is mortifed into the 
frame-work, and ferves as a reft for the end of the iron 
axis C, which is next to the handle. On each extremity 
of fuch axis there is a (houlder, which keeps it fteady in 
its place. Laftly, there is a cloth hood fixed to a broad 
wooden hoop, which is placed over the (tones while work¬ 
ing, to prevent the finer particles of flour from efcaping. 
Fig. 19. reprefents the bolter, with its front removed, in 
order to dilplay its interior ftrufture ; the machine being 
3 feet 10 inches in length, 19J inches in breadth, and 18 
inches in depth. A is a moveable partition, Hiding 
about four feet backwards or forwards, from the centre 
of the box, upon two wooden ribs, which are fixed to the 
back and front of the box,and one of which is delineated 
at the letter B. C, the lid of the bolter, reprelented open. 
I>, a Aider, which is moveable in a groove made in the 
lid, by means of two handles on the back of fuch lid. 
E, a forked iron, fixed in the Aider D, and which, when 
the lid is (hut, takes hold of the edge of the fieve F, and 
moves it backward and forward on the wooden ribs B, 
according to the agitation of the Aider. G reprefents 
a fixed partition in the lower centre of the box, which it 
divides into two parts, in order to feparate the fine from 
the coarfe flour ; from this partition the Aider A moves 
each way about four inches, and thus affords room for 
working the fieve. H, a board that is parallel to the 
bottom of the bolter, and forms part of the Aider A; this 
board ferves to prevent any of the fitted matter from 
failing into the other partition. I, I, reprefent two of the 
back feet, which fupport the bolter.' Fig. 30. is a view 
of the top, or upper part, of the lid of the bolter. K, 
tile Aider that moves the lengthwile of the bolter. L, L, 
die handies by which the Aider is worked. M, a ferew, 
ferving to hold the fork, which imparts motion to the 
fieve. Fig. 31. reprefents the forked iron E, feparateiy 
from the lid. 
The particular excellence of this mill confifis in the 
circumftance, that, from the vertical pofition of its (tones, 
it may be put in afifion without the intervention of cogs 
or wheels. It may be employed in the grinding of malt, 
the broiling of oats for horfes, and for making flour, or 
for all thefe purpofes : it may likewife be eafily altered, 
fo as to grind either of thofe articles to a greater or lefs 
degree of finenefs. Another advantage is, that one man 
is fufneient to work it; though, if two perfons, namely, 
a man and a boy, be employed, they will be able to pro¬ 
duce, in the courfe of two hours, a quantity of flour fuf- 
ficient to ferve a family, confiding of fix or eight perfons, 
for a whole week : repeated fatisfaefory trials have proved, 
that this miil grinds the corn completely, and at the rate 
of one buftiel of wheat within the hour. Befides, the in- 
dultrious farmer will thus be enabled to make compara¬ 
tive experiments on the quality of his grain, and may 
furnifti himfelf, at a trifling expenfe, with flour from his 
own wheat, without apprehending any adulteration ; or 
without being expofed to the impofitions, or caprice, of 
fraudulent and avaricious millers. Laftly, though Mr. R.’s 
bolter be more particularly calculated for fifting flour, it 
may alfo be applied to various other ufeful purpoies, and 
efpecially with a view to obviate the inconveniences nec-ef- 
farily attendant on the levigation of noxious fubftances, 
and to prevent the wafte of their finer particles. The 
price of the whole apparatus, delivered free of carriage in 
London, is twenty guineas. 
Another family corn-mill, by Mr. Charles Williams, of 
Hatfield fireet, Blackfriars-road, was rewarded by the fame 
fociety, in the year 1814, with twenty guineas and the fil- 
ver medal. Fora defeription of this, we muft refer to the 
Tranfactions of the Society, vol. xxxii. 
A Hand Thrashing-Machine. 
The thrafliing-niachine is confidered as a very late in¬ 
vention. It is not, however, abfolutely fo, though it is 
only within a few years that it has been brought into fre¬ 
quent ufe. As long ago as the year 1732, a thrafliing- 
machine was manutafhired by Mr. Michael Menzies, of 
Edinburgh ; and he obtained a patent for it. It confided, 
as far as we have been able to afeertain, of numerous in- 
ftruments, refembling flails, which were attached to a move- 
able beam, and inclined to the latter in an angle of ten 
degrees. O11 each fide of fuch beam were placed floors, or 
benches, on which tiie (heaves Were fpread ; the flails 
being moved forward and backward on thefe benches by 
a crank that was fixed to the end of an axle, revolving 
about thirty times in a minute. 
The fecond machine was invented in 1753, by Mr. Mi¬ 
chael Sterling, of Dumblaine, Perthfhire : ids firft models 
were very imperfeft; bur, after repeated alterations, he 
completed it in its prefent form in 1758 ; and it now con- 
fifts of an outer or water wheel, having an inner wheel 
furnilhed with forty-eight cogs, and turning on the fame 
axle. With this cog-wheel is connected g vertical trun¬ 
dle, or pinion, with (even notches ; and the axle of which 
paffes through a floor above the wheel; its upper pivot 
being fecured in a beam fix inches above the floor. At the 
height of three feet three inches from the latter, two ftraight 
pieces of fquared wood (each being four feet in length) 
are infected through the axle of the pinion, at right an¬ 
gles, fo as to form four arms that are moved round hori¬ 
zontally. To the end of thefe arms are affixed four iron 
plates, each twenty inches in length, and eight inches in 
breadth at the extremity neareft tothe arms, but tapering 
to a point at the oppofite ends. The horizontal fly, here 
deferibed, conftitutes four thrafliers, and is incloled in a 
cylindrical wooden box, that is three feet and a half high, 
and eight feet in diameter : on the top of this box is an 
opening eight inches in width, extending a foot and a half 
from the circumference to the centre, and through which 
1 the 
