To this end (see [figs. 2 and 4], of the same [Plate]) I place two, four, or more boxes a, b, c, d, on as many wheels e f, toothed on my Patent principle; the latter, in the present case, being about two feet in diameter, and the boxes, in length, three quarters of that diameter: and of any convenient width, according to the size of the pieces. The wheels e f are mounted on the strong shafts C D, which run, below, in the wheel E; and by which, also, they are turned round the common centre, by means of the vertical wheel F. Further, in the centre, and between the wheels e f, I place the bevil wheel i, of half the diameter, in which the main shaft runs loosely, and which is itself fixed to the upper frame work, so as not to turn at all. The three Patent teeth at e i f shew that these wheels are to geer into each other on that principle: and it is likewise seen that this whole mechanism is included in a set of rails, of an octagonal form, for the purpose of preserving the men from danger, while in the act of charging and discharging the boxes. And here it is worthy of some remark, that this process must be easier, and more quickly performed, with these open boxes, than through holes made in the vertical side of a Dash-wheel, on the usual principle.
To account, now, for the sloping position of the shafts C D, and the consequent slope of the boxes, they are thus placed, in order that the goods may not drag too much on the bottoms of the boxes, when passing from one end of them to the other. Instead of this, they are, in fact, thrown, by the centrifugal force, from the inner angle h ([fig. 2]) to some point k up that side of the box which is then outwards; where they strike, and then fall into the contiguous angle under k, to be again projected thence, after one revolution round the common centre; for, it should here be remembered, that, by the given proportion of the wheels, the circulating wheels e f turn on their own axes exactly one half round, for every whole revolution round the common centre A B.
To elucidate this still further, I have outlined, at A [fig. 1], the central wheel i, of [fig. 2], together with one of the excentric wheels B, and the lines a b, a b, &c., representing the boxes, are supposed to be wires with the balls b b, &c. sliding on them, as is usual in some experiments on the Whirling Machine—(See “Ferguson’s Lectures,”) Of these wires, I have given the true directions in 12 positions of the wheel B: the epicycloid b b b, &c., shewing the steps by which the ball b is brought toward the common centre, during three quarters of the revolution; and also the position of the wire on which it slides: where it is evident that the ball b has a tendency to preserve it’s station, at the first end of the wire, until the latter takes the position b b c, when it forms (or nearly) a tangent to the curve, and is, at the same time, at right angles to the radius of motion, A b d. From this moment, then, the ball is free to leave the centre, and to fly off in a tangent with the velocity with which the curve itself is generated at that point. We might, thus, during the rest of it’s flight, seek it somewhere in the line b f g; but, as the wire continues to change it’s position, and must turn half round on it’s own axis, by the time it arrives at B b, or describes a quarter-circle on the common centre, it will again overtake the ball—and, giving it a curvilinear direction, will finally carry it to it’s other extremity, at or near the point B—where it’s motion first began: and thus shall we give as many strokes to the ball, as half turns to the wheel B; or, in other words, as many dashes to the cloth, as we give turns to the boxes, round the common centre.
By this process, then, substituted for that of the common Dash-wheel, we can increase almost indefinitely, the number of passages of the cloth from one end of the boxes to the other; and the force of the dash will be as the squares of those numbers; since (as Ferguson expresses it) “a double centrifugal force balances a quadruple power of gravity.” If, then, with four boxes we turn this machine 60 times in a minute, we shall have 240 strokes in that time, instead of about 90 given by a common Dash-wheel; and this difference might be more than doubled, if so desired: for should, then, the stroke be found too severe, the boxes might be shortened, so as to lessen it’s violence, though preserving all it’s frequency.
There are two other objects that present enough analogy to this Washing process, to be here mentioned. The first is the operation of Fulling, as applied to woollen cloths in general. That process, I fear, is not performed at present in the best manner possible; and I feel persuaded that the centrifugal motion might be applied to it with advantage—whether as to quantity of produce, or perfection of effect: and having thus said, I shall leave the idea to the riper judgment of my manufacturing readers.
The second object I shall just introduce is, that of Kneading Dough, for bread, by the same centrifugal agency. It is well known, that an ingenious baker, of Paris, invented, some time ago, a method of kneading; which consists in letting the lump of dough fall successively from the four sides of a square box, revolving on a horizontal centre. As this idea seems to have succeeded perfectly, I offer the Centrifugal System, as tending to quicken, almost indefinitely, such a process; and I particularly recommend it to the attention of Government, and of all large establishments as a mean of doing well and rapidly, by power, what is frequently done slowly and ineffectually, by the usual methods. Verbum sat.