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sized walk; one of these intended for cutting and boring tenons, used in this gentleman's hollow masts, is represented in fig. 454.

NOPQR is a hollow frame, under which is part of the wheel-work of the horse-mill, ABCDE F are pullies, over which pass straps or bands, the parts of which out of sight run upon the rim of a large vertical wheel; by means of this simple apparatus the saws SS are made to revolve upon their axles, with an equal velocity, the same band passing round the pullies DC, upon those axles; and the rotatory motion is given to the borer G by the band passing over the pulley A. The board I is inclined to the horizon in an angle of about 30 degrees; the plane of the saw S is parallel to that of the board I, and about a quarter of an inch distant from it, while the plane of the saw S' is vertical, and its lowest point at the same distance from the board I. Each piece of wood K, out of which the tenon is to be cut, is about four inches long, and an inch and a quarter broad, and § of an inch thick. One end of such piece is laid so as to slide along the ledge at the lower part of the board I, and as it is pushed on, by means of the handle H, it is first cut by the saw S, and immediately after by the saw S'; after this the other end is put lowest, and the piece is again cut by both saws : then the tenon is applied to the borer G, and as soon as a hole is pierced through it, it is dropped into the box beneath.

By the above process, at least 30 tenons may be completed in a minute, with greater accuracy than a man could make one in a quarter of an hour with the common hand saw and gimlet. Similar contrivances may, by slight alterations, be fitted for many other purposes, particularly all such as may require the speedy sawing of a great number of pieces into exactly the same size and shape. A very great advantage attending this sort of machinery is, that when once the position of the saws and frame is adjusted, a common labourer may perform the business just as well as the best workman.

BARK-MILL.

THE bark-mill is constructed for the purpose of grinding and preparing bark till it is fit for the tanner.

Bark-mills, like most other mills, are worked either by means of horses, by water, or by wind.

One of the best mills we have seen described for these purposes is that invented by Mr. Bagnall, of Worsley, in Lancashire. This machine will serve not only to chop bark, to grind, to riddle, and pound it; but to beam or work green hides and skins out of the mastering or drench, and make them ready for the ouse or bark-liquor; to beam sheep-skins, and other skins, for the skinner's use; and to scour and take off the bloom from tanned leather, when in the currying state.

Fig. 455 is a horizontal plan of the mill; fig. 456 a longitudinal section of it; fig. 457 a transverse section of it.

A, the water-wheel, by which the whole machinery is worked.

B, the shafts.

C, the pit-wheel, which is fixed on the water-wheel shaft B, and turns the upright shaft E, by the wheel F, and works the cutters and hainmer by tapets.

D, the spur and bevel wheels at the top of upright shafts.

E, the upright shaft.

F, the crown-wheel, which works in the pit-wheel C.

G, the spur-nut to turn the stones I.

P, the beam, with knives or cutters fixed at the end to chop or cut the park, which bark is to be put upon the cutters or grating i, on which the beam is to fall.

Q, the tryal that receives the bark from the cutters i, and conveys it into the hopper H, by which it descends through the shoe J to the stones Iy where it is ground.

K, the spout, which receives the bark from the stones, and conveys it into the tryal L; which tryal is wired, to shift or dress the bark as it descends from the stones I.

M, the trough, to receive the bark that passes through the tryal L.

R, the hammer, to crush or bruise the bark that falls into the dish S, which said dish is on the incline, so that the hammer keeps forcing it out of the lower side of the said dish, when bruised.

k, a trough, to receive the dust and moss that passes through the tryal Q. T, the bevel-wheel that works in the wheel D, which works the beamknife by a crank V, at the end of the shaft u.

W, the penetrating-rod, which leads from the crank V to the start x.

a, the start, which has several holes in it to lengthen or shorten the stroke of the beam-knife.

y, the shaft, to which the slide-rods h h are fixed by the starts n n.

h, the slide rod, on which the knife ƒ is fixed, which knife is to work the hides, &c. On the knife are two springs a a, to let it have a little play as it makes its strokes backwards and forwards, so that it may not scratch or damage the hides, &c.

z, is a catch in the slide rod h, which catches on the arch-head e; and the said arch-head conveys the knife back without touching the hide, and then falls back to receive the catch again.

1, the roller to take up the slide-rod h, while the hides are shifting on the beam b, by pulling at the handle m.

b, the beam to work the hides, &c. on. Each beam has four wheels, p p, working in a trough-road, g g, and removed by the levers e c. When the knife has worked the hides, &c. sufficiently in one part, the beam is then shifted by the lever e as far as is wanted.

d, a press, at the upper end of the beam, to hold the hide fast on the beam while working.

e, an arch-head, on which the slide-rod h catches.

f, the knife fixed on the slide-rod h, to work the hides, &c.

i, cutters or grating to receive the bark for chopping.

The beam P, with knives or cutters, may either be worked by tapets, as described, or by the bevel-wheel T with a crank, as V, to cut the same as shears.

The knife fis fixed at the bottom of the start, which is fixed on the sliderod h; the bottom of the start is split open to admit the knife, the width of one foot; the knife should have a gudgeon at each end, to fix in the open

part of the start; and the two springs a a prevent the knife from giving too much way when working. The knife should be one foot long, and four or five inches broad.

The arch-head e will shift nearer to or further from the beam h, and will be fixed so as to carry the knife back as far as is wanted, or it may be taken away till wanted.

The roller is taken up by pulling at the handle m, which takes up the slide-rod so high as to give head room under the beam-knife; the handle may be hung upon a hook for that purpose. The slide-rod will keep running upon the roller all the time the hide is shifting; and when the hide is fixed, the knife is put on the beam again by letting it down by the handle m. There may be two or more knives at work on one beam at the same time, by having different slide-rods; there should be two beams, so that the workman could be shifting one hide, &c. while the other was working. The beam must be flat, and a little on the incline; as to the breadth, it does not matter; the broader it is, the less shifting of the hides will be wanted, as the lever c will shift them as far as the width of the hide, if required. Mr. Bagnall has formed a kind of press d, to let down, by a lever, to hold the hide fast on each side of the knife, if required, so that it will suffer the knife to make its back stroke without pulling the hide up as it comes back. The slide-rod may be weighted, to cause the knife to lay stress on the hide, &c. according to the kind and condition of the goods to be worked.

Hides and skins for the skinner's use are worked in the same way as for the tanner's.

Scouring of tanned leather for the currier's use can be done on the beam, the same as working green hides; it is only taking the knife away, and fixing a stone in the same manner as the knife by the said joint, and to have a brush fixed to go either before or after the stone. The leather will be much sooner and better secured this way than by hand.

The whole machinery may be worked by water, wind, steam, or any other power; and that part of the machinery which relates to the beaming part of the hides, may be fixed to any horse bark-mill, or may be worked by a horse or other power separately.

OIL-MILLS.

As these kingdoms do not produce the olive, it would be needless to describe the mills which are employed in the southern parts of Europe; we shall therefore content ourselves with a description of a Dutch oil-mill, employed for grinding and pressing linseed, rapeseed, and other oleaginous grains; and, to accommodate our description still more to our local circumstances, shall employ water as the first mover; thus avoiding the enormous expense and complication of a windmill.

Description of fig. 458.

1 is the elevation of a wheel, over or under shot, as the situation may require.

the bell-metal socket, supported by masonry, for receiving the outer gudgeon of the water-wheel.

[blocks in formation]

1, a spur-wheel upon the same axis, having 52 teeth.

2, the trundle that is driven by No. 1, and has 78 staves.

3, the wallower, or axis for raising the pestles. It is furnished round its circumference with wipers for lifting the pestles, so that each .nay fall twice during one turn of the water-wheel: that is, three wipers for each pestle.

4, a frame of timber, carrying a concave half cylinder of bell-metal, in which the wallower (cased in that part with iron plates) rests and turns round. 5, masonry supporting the inner gudgeon of the water-wheel and the above-mentioned frame.

6, gudgeon of the wallower, which bears against the bell-metal step fixed in the wall. This double support of the wallower is found to be necessary in all mills which drive a number of heavy stampers.

Fig. 460 is the elevation of the pestle and press-frame, their furniture, the mortars, and the press-pestles.

1, the six pestles.

2, cross-pieces between the two rails of the frame, forming, with these rails, guides for the perpendicular motion of the pestles.

3, the two rails; the back one is not seen. They are checked and bolted into the standards, No. 12.

4, the tails of the lifts, corresponding with the wipers upon the wallower. 5, another rail in front, for carrying the detents which hold up the pestles when not acting. It is marked 14, in fig. 464.

6, a beam a little way behind the pestles; to this are fixed the pulleys for the ropes, which lift and stop the pestles. It is represented by 16, in fig. 464. 7, the said pulleys with their ropes.

8, the driver which strikes the wedge that presses the oil.

9, the discharger, a stamper which strikes upon the inverted wedge, and loosens the press.

10, the lower rail with its cross-pieces, forming the lower guides of the pestles.

11, a small cog-wheel upon the wallower for turning the spatula, which stirs about the oil-seed in the chauffer-pan. It has 28 teeth, and.is marked No. 6, in fig. 464.

12, the four standards, mortised below into the block, and above into the joists and beams of the building.

13, the six mortars hollowed out of the block itself, and in shape pretty much like a kitchen-pot.

14, the feet of the pestles rounded into cylinders, and shod with a great lump of iron.

15, a board behind the pestles, standing on its edge, but inclining a little backwards. There is such another in front, but not represented here. These form a sort of trough, which prevents the seed from being scattered about by the fall of the pestles, and lost.

16, the first press-box, (also hollowed out of the block,) in which the grain is squeezed, after it has come for the first time from below the mill-stones. 17, the second press-box, at the other end of the block, for squeezing the grain after it has passed a second time under the pestles.

18, frame of timber for supporting the other end of the wallower in the same manner as No. 4, fig. 459.

19, small cog-wheel on the end of the wallower, for giving motion to the nill-stones; it has 28 teeth.

20, gudgeon of the wallower, bearing on a bell-metal socket fixed in the wall. 21, vessels for receiving the oil from the press-boxes.

Fig. 461, Elevation and mechanism of the mill-stones.

1, upright shaft, carrying the great cog-wheel above, and the runner millstones below in their frame.

2, cog-wheel of 76 cogs, driven by No. 19 of fig. 460.

3, the frame of the runners.

4, the innermost runner, or the one nearest the shaft.

5, outermost ditto, being farther from the shaft.

In

6, the inner rake, which collects the grain under the outer runner. 7, the outer rake, which collects the grain under the inner runner. this manner the grain is always turned over and over, and crushed in every direction. The inner rake lays the grain in a slope, of which fig. 465 is a section; the runner flattens it, and the second rake lifts it again, as is marked in fig. 466; so that every side of the grain is presented to the millstone, and the rest of the legger or nether mill-stone is so swept by them, that not a single grain is left on any part of it. The outer rake is also furnished with a rag of cloth, which rubs against the border or hoop that surrounds the nether mill-stone, so as to drag out the few grains which might otherwise remain in the corner.

8, the ends of the iron axle which passes through the upright shaft, and through the two runners. Thus they have two motions: first, a rotation round their own axis; secondly, that by which they are carried round upon the nether mill-stone, on which they roll. The holes in these mill-stones are made a little wide; and the holes in the ears of the frame, which carry the ends of the iron axes, are made oval up and down. This great freedom of motion is necessary for the runner mill-stones, because frequently more or less of the grain is below them at a time, and they must therefore be at liberty to get over it without straining, and perhaps breaking, the shaft.

9 and 10, the border or hoop which surrounds the nether mill-stone. 11 and 12, the nether mill-stone and masonry which support it.

Fig. 462, plan of the runner mill-stones, and the frame which carries them round.

1, 1, are the two mill-stones.

3, 3, 3, 3, the outside pieces of the frame.

4, 4, 4, 4, the cross-bars of the frames, which embrace the upright shaft 3, and give motion to the whole.

6, 6, the iron axis upon which the runners turn.

7, the outer rake.

8, the inner ditto.

Fig. 463 represents the nether mill-stone seen from above. 1, the wooden gutter which surrounds the nether mill-stone.

2, the border or hoop, about six inches high all round, to prevent any seed being scattered.

3, an opening or trap-door in the gutter, which can be opened or shut at pleasure; when open, it allows the bruised grain, collected in and shoved along the gutter by rakes, to pass through into troughs placed below to

receive it.

4. portion of the circle described by the outer runner.

5, portion of the circle described by the inner one. By these we see that the two stones have different routes round the axis, and bruise more seed. 6, the outer rake.

7, the inner ditto.

8, the sweep, making part of the inner rake, occasionally let down for

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