About the year 1787, Messrs. Kendrew and Porthouse, of Darlington, obtained a patent for spinning a flaxen thread by means of machinery; prior to that time, we believe, the rock and wheel, variously modified, occasionally for superior spinners to form two threads at once, were universally employed. In Ireland especially, even at the present day, this method is much practised. The flax, rendered straight and smooth by hackling, is wrapped loosely round the rock, from which it is gradually drawn by the left hand, whilst the thumb and fore-finger of the right, moistened with water, are employed in adjusting the fibres, and directing the thread. A bobbin and flyer, placed upon a horizontal spindle, serve to give the twist, and to take up the finished thread; their motion is derived from a wheel, impelled by the foot through a treadle and crank, by means of an endless-band passing round a pulley of much smaller diameter, which is fixed upon the spindle.

The straightness and smoothness of the fibres of flax, so different from the corrugation and adhesiveness of cotton and wool, with their extraordinary length, seemed to demand an arrangement in machine-spinning very different from what has been already delineated.

In the patent alluded to, the hackled flax was extended upon a horizontal frame, at fig. 410, to be carried between the rollers Bb, and afterwards to pass along with the cylinder C, (revolving with a velocity equal to that of any point of the circumference of B,) under several successive rollers, until it arrived at the drawing-rollers Dd; the twist and removal of the thread then taking place by the flyer and bobbin, as before described. The rollers E, F, G, H, I, if of equal weights, will, on account of their respective positions, press with unequal force; the one resting upon the vertex of the cylinder being evidently the most efficacious, and with the surface beneath acting probably the part of a pair of holding-rollers to fibres of the length of nearly one-fourth of the circumference; whilst for fibres which are longer or shorter, the other rollers, according to their place, will answer the same purpose. In this, however, there is no new principle; and although modified, it amounts merely to the operation of holding and drawing rollers. From some impediments thrown in the way of the Scotch flax-spinners by the patentees before mentioned, they began, we believe, in no long time, to place their rollers in a straight line, at distances suitable to the length of the fibres. Of the excellence of this arrangement a working model made for the Andersonian Institution in Glasgow, in the year 1803, afforded sufficient evidence.

We shall now proceed to give a description of a patent, obtained, in the year 1806, by Messrs. Clarke and Bugby, for effecting certain improvements in a machine, intended to be worked by hand-labour, for the spinning of hemp, flax, tow, and wool.

Fig. 445 represents an oblique view of the front of a frame containing ten spindles, (but frames may contain an indefinite number of spindles.) A,

the spindle or a bow passing through the whole frame, having ten bosses of brass or cast-iron thereon, each about four inches diameter, each boss supplying one spindle; B, a pinion of twelve leaves upon the end of the spindle A, connected with the wheel C, of eighty teeth, fixed upon the end of a small iron spindle F, covered with wood and extending through the whole frame; D, a slack or intermediate pinion of any size at discretion, connected with another similar pinion, the latter connected with a wheel of 120 teeth, which is fixed upon an iron spindle G, of about 14 inch diameter, and extending through the whole frame; but the wheels B CD and E may be varied in their numbers, to increase or diminish the draught of the substance operated upon, as may best suit its quality or the ideas of the workman. The pinion B is so contrived as to slip off the end of the spindle A, to make room for a smaller or larger one; by means whereof a larger or shorter thread may be spun from the same sized rovings; a а á á á á á á á а represent ten roved slivers of hemp, flax, tow, or wool, passing between the iron spindle G and rollers in pairs pressed against them by springs or weights; these springs or weights must be of sufficient force to hold back the slivers or rovings so securely, that they may only pass on with the movement of the spindle; these pairs of pressing rollers are placed behind the spindle. The use of the small iron spindle F, covered with wood, and left rather larger than the spindle G, is, with pressure of the small wood roller, made up in pairs bbbbb, and so contrived that each pair may roll upon two slivers, to bring them down straight, and preserve the twist which they receive in the roving-machine till the slivers leave them. The bosses on the spindle A have likewise wooden rollers in pairs pressed against them by springs or weights, between which the drawn, lengthened, or extended slivers pass to the spindle, the rollers having each a tin conductor ccccccccct, to bring the material under operation as centrically as possible between the wood rollers and the bosses; but all the above-mentioned parts of the machine is so similar to the common upright frames for spinning flax, that a person conversant with them will not be at a loss to make it all. His a wheel of wood four feet in diameter, having its rim about two inches thick, with a groove in its periphery for a small cord or band. In its centre is a rule or stock of wood through which the spindle I passes, and extends into its frame about one-fourth of its length. To enable the person that turns the winch to reach all the spindles at work, with the hand that is not engaged in turning, to remove any obstacle that may arise to the spindles, the arbor or spindle of the wheel I has its bearing on the sides of the frame that contains it, marked LLLL; this frame, with the wheel H, the arbor I, and the winch K, is similar to that part of a machine called a mule-jenny, used for spinning cotton; this frame is supported in a horizontal position at the outer end by two legs marked M M, and a screw pin which passes through K, the front upright, a A, fig. 444, and made tight with the thumb screw a; the screw passes through a groove or mortise at the end of the wheel frame, to enable the workman to adjust the wheels N and O, as it will be found necessary to change the wheel N, to make such alteration in the twist as the size of the yarn may require, or as the workman may think proper. P and Q are bevel wheels of equal size, the former fixed upon the rule or stock of the wheel H, and connected with Q upon the spindle R, taking round with it the wheel N, which is connected with the wheel 0. Upon the embossed spindle or arbor A, a aa aa aa aa a, are spindles standing on a carriage with four wheels, similar to the carriages used in mule-jennies for spinning cotton, having at each of them, at d d d d d d d d d d, a convex seat of wood of any convenient size, not less than the bottom of the bobbins or quills eeeeeeeeee; these bobbins or quills are about six