in Commerce, the act or art of reducing silk, flax, hemp, wool, hair or other matters, into thread. Spinning is either performed on the wheel, or with a distaff and spindle, or with other machines proper for the several kinds of working. Hemp, flax, nettle-thread, and other like vegetable matters, are to be wetted in spinning; silks, wools, &c. are spun dry, and do not need water; yet there is a way of spinning or reeling silk as it comes off the cases or balls, where hot and even boiling water is to be used (see Silk). The vast variety, and the importance of those branches of our manufactures, which are produced from cotton, wool, and flax, spun into yarn, together with the cheapness of provisions, and the low price of labour in many foreign countries, which are our rivals in trade, have occasioned many attempts at home to render spinning more easy, cheap, and expeditious; for which see COTTON-Spinning and COTTON MILLS.

To give an intelligible and accurate description of a cotton mill would be abundant employment for a volume. Our limits admit of nothing like this; but as we are certain that many of our readers have viewed a cotton mill with wonder, but not with intelligence, or with leisure to trace the steps by which the wool from the bag ultimately assumes the form of a very fine thread. Bewildered by such a complication of machinery, all in rapid motion, very few, we imagine, are able to recollect with distinctness and intelligence the essential part of the progress by which the form of the cotton is so wonderfully changed. Such readers will not think a page or two misemployed, if they are thereby able to understand this particular, to which all the rest of the process is subservient.

We pass over the operation of carding, by which all the clots and inequalities of the cotton wool are removed, and the whole is reduced to an uniform thin fleece, about 23 inches broad. This is gradually detached from the finishing card, and, if allowed to hang down from it, would pile up on the floor as long as the mill continues to work; but it is guided off from the card, very tenderly, in a horizontal direction, by laying its detached end over a roller, which is slowly turned round by the machine. Another roller lies above the fleece, pressing it down by its weight. By this prelude, a gentle hold is taken of the fleece, and therefore the slow motion of the rollers draws it gently from the card at the same rate as it is disengaged by the comb; but between the card and the rollers a set of smooth pins are placed in two rows, leading from the card to the rollers, and gradually approaching each other as we approach the rollers. By these pins the broad fleece is hemmed in on both sides, and gradually contracted to a thick roll; and in this state passes between the rollers, and is compressed in a pretty firm flat riband, about two inches broad, which falls off from the rollers, and piles up in deep tinplate cans set below to receive it.

It is upon this stripe or riband of cotton wool that the operation of spinning begins. The general effect of the spinning process is to draw out this massive roll, and to twist it as it is drawn out. But this is not to be done by the fingers, pulling out as many cotton fibres at once as are necessary for composing a thread of the intended fineness, and continuing this manipulation regularly across the whole end of the riband, and thus, as it were, nibbling the whole of it away. The fingers must be directed, for this purpose, by an attentive eye. But in performing this by machinery, the whole riband must be drawn out together, and twisted as it is drawn. This requires great art, and very delicate management. It cannot be done at once; that is, the cotton roll cannot first be stretched or drawn out to the length that is ultimately produced from a tenth of an inch of the roll, and then be twisted. There is not cohesion enough for this purpose; we should only break off a bit of the roll, and could make no farther use of it. The fibres of cotton are very little implicated among each other in the roll, because the operation of carding has laid them almost parallel in the roll; and though compressed a little by its contraction from a fleece of 25 inches to a riband of only two, and afterwards compressed between the discharging rollers of the carding machine, yet they cohere so slightly, that a few fibres may be drawn out without bringing many others along with them. For these reasons, the whole thickness and breadth of two or three inches of the riband is stretched to a very minute quantity, and then a very slight degree of twist is given it, viz. about three turns in the inch; so that it shall now compose an extremely soft and pungy cylinder, which cannot be called a thread or cord, because it has scarcely any firmness, and is merely rounder and much flenderer than before, being stretched to about thrice its former length. It is now called slab, or roove.

Although it be still extremely tender, and will not carry a weight of two ounces, it is much more cohesive than before, because the twist given to it makes all the longitudinal fibres bind each other together, and compress those which lie athwart; therefore it will require more force to pull a fibre from among the rest, but still not nearly enough to break it. In drawing out a single fibre, others are drawn out along with it; and if we take hold of the whole assemblage, in two places, about an inch or two inches asunder, we shall find that we may draw it to near twice its length without any risk of its separating in any intermediate part, or becoming much smaller in one part than another. It seems to yield equably over all.

Such is the state of the slab or roove of the first formation. It is usually called the preparation; and the operation of spinning is considered as not yet begun. This preparation is the most tedious, and requires more attendance and hand labour than any subsequent part of the process. For the stripes or ribands from which it is made are so light and bulky, that a few yards only can be piled up in the cans set to receive them. A person must therefore attend each thread of slab, to join fresh stripes as they are expended. It is also the most important in the manufacture: for as every inch of the slab meets with precisely the same drawing and the same twisting in the subsequent parts of the process, therefore every inequality and fault in the slab (indeed in the fleece as it quits the finishing card) will continue through the whole manufacture. The spinning of cotton yarn now divides into two branches. The first, performed by what are called jennies, perfectly resembles the ancient spinning with the distaff and spindle; the other, called spinning of twist, is an imitation of the spinning with the fly-wheel. They differ in the same manner as the spinning with the old wool or cotton wheel differs from the spinning with the flax-wheel. Mr Arkwright's chief invention, the substitution of machinery for the immediate work of the human finger, is seen only in the manufacture of twist. We shall therefore confine our attention to this.

The rest of the process is little more than a repetition of that gone through in making the first slab or roove. It is formed on bobbins. These are set on the back part of the drawing frame; and the end of the slab is brought forwards toward the attending workman. As it comes forward, it is stretched or drawn to about four-thirds of its former length, or lengthened one-third; and is then twisted about twice as much as before, and in this state wound up on another bobbin. In some mills two rooves, after having been properly drawn, are brought together through one hole, and twisted into one; but we believe that, in the greater number of mills, this is deferred to the second drawing. It is only after the first drawing that the produce of the operation gets the name of slab; before this it is called preparation, or roove, or by some other name. The slab is still a very feeble, soft, and delicate yarn, and will not carry much more weight than it did before in the form of roove. The perfection of the ultimate thread or yarn depends on this extreme softness; for it is this only which makes it susceptible of an equal stretching; all the fibres yielding and separating alike.

The next operation is the second drawing, which no way differs from the first, except in the different proportionings of the lengthening, and the proportion between the lengthening and the subsequent twist. On these points we cannot give any very distinct information. It is different in different mills, and with different species of cotton wool, as may be easily imagined. The immediate mechanism or manipulation must be skillfully accommodated to the nature of that friction which the fibres of cotton exert on each other, enabling one of them to pull others along with it. This is greatly aided by the contorted curled form of a cotton fibre, and a considerable degree of elasticity which it possesses. In this respect it greatly resembles woollen fibres, and differs exceedingly from those of flax; and it is for this reason that it is scarcely possible to spin flax in this way: its fibres become lank, and take any shape by the slightest compression, especially when damp in the slightest degree. But besides this, the surface of a cotton fibre has a harshness or roughness, which greatly augments their mutual friction. This is probably the reason why it is so unfit for tents and other dressings for wounds, and is refused by the surgeon even in the meanest hospitals. But this harshness and its elasticity fit it admirably for the manufacture of yarn. Even the shortness of the fibre is favourable; and the manufacture would hardly be possible if the fibre were thrice as long as it generally is. If it be just so long that in the finished thread a fibre will rather break than come out from among the rest, it is plain that no additional length can make the yarn any stronger with the same degree of compression by twining. A longer fibre will indeed give the same firmness of adhesion with a smaller compression. This would be an advantage in any other yarn; but in cotton yarn the compression is already as slight as can be allowed; were it less, it would become woolly and rough by the smallest usage, and is already too much disposed to teaze out. It can hardly be used as sewing thread. Now suppose the fibres much longer; some of them may chance to be stretched along the slab through their whole length. If the slab is pulled in opposite directions, by pinching it at each end of such fibres, it is plain that it will not stretch till this fibre be broken or drawn out; and that while it is in its extended state, it is acting on the other fibres in a very unequal manner, according to their positions, and renders the whole apt to separate more irregularly. This is one great obstacle to the spinning of flax by similar machinery; and it has hitherto prevented (we believe) the working up of any thing but the flours or tow, which is separated from the long fine flax in the operation of hatching.

A third, and sometimes even a fourth, drawing is given to the slab formed on the bobbins of this second operation. The slab produced is now a slender, but still extremely soft cord, susceptible of considerable extension, without risk of separation, and without the smallest chance of breaking a single fibre in the attempt. In one or more of the preparatory drawings now described, two, and sometimes three slabs, of a former drawing, are united before the twist is given them. The practice is different in different mills. It is plain, that unless great care be taken to preserve the slab extremely soft and compressible during the whole process, the subsequent drawing becomes more precarious, and we run a risk of at last making a bad loose thread instead of a uniform and simple yarn. Such a thread will have very little lateral connection, and will not bear much handling without separating into strands. The perfection of the yarn depends on having the last slab as free of all appearance of strands as possible.

The last operation is the spinning this slab. This hardly differs from the foregoing drawings in anything but the twist that is given it after the last stretching in its length. This is much greater than any of the preceding, being intended to give the yarn hardness and firmness, so that it will now break rather than stretch any more.

The reader, moderately acquainted with mechanics, cannot but perceive that each of the operations now described, by which the roove is changed into the soft slab, and each of these into one flenderer and somewhat firmer, by alternately teazling out and twining the soft cord, is a substitute for a single pull of the finger and thumb of the spinner, which the accommodates precisely to the peculiar condition of the lock of wool which she touches at the moment. She can follow this through all its irregularities; and perhaps no two succeeding plucks are alike. But when we cannot give this momentary attention to every minute portion, we must be careful to introduce the roove in a state of perfect uniformity; and then every inch being treated in the same manner, the final result will be equable—the yarn will be uniform.

We are now to describe the mechanism by which all this is effected. But we do not mean to describe a cotton mill; we only mean to describe what comes into immediate contact with the thread; and in so doing, to confine ourselves to what is necessary for making the reader perceive its ability to perform the required task. We see many cases where individuals can apply this knowledge to useful purposes. More than this would, we think, be improper, in a national point of view.

Let ABC (fig. 1.) represent the section of a roller, whose pivot D does not turn in a pivot hole, but in the bottom of a long narrow notch DE, cut in an iron standard. abc is the section of another iron roller, whose pivot d is in the same notches at each end, while the roller itself lies or rests on the roller ABC below it. The surfaces of these rollers are fluted lengthwise like a column: only the flutings are very small and sharp, like deep strokes of engraving very close together. It is plain, that if the roller ABC be made to turn slowly round its axis by machinery, in the direction ABC (as expressed by the dart), the roughness of the flutings will take hold of the similar roughness of the upper roller abc, and carry it round also in the direction of the dart, while its pivots are engaged in the notches DE, which they cannot quit. If therefore we introduce the end F of the cotton string or ribbon, formed by the carding machine, it will be pulled in by this motion, and will be delivered out on the other side at H, considerably compressed by the weight of the upper roller, which is of iron, and is also pressed down by a lever which rests on its pivots, or other proper places, and is loaded with a weight. There is nothing to hinder this motion of the ribbon thus compressed between the rollers, and it will therefore be drawn through from the cans. The compressed part at H would hang down, and be piled up on the floor as it is drawn through; but it is not permitted to hang down in this manner, but is brought to another pair of sharp fluted iron rollers K and L. Supposing this pair of rollers to be of the same diameter, and to turn round in the same time, and in the same direction, with the rollers ABC, abc; it is plain that K and L drag in the compressed ribbon at I, and would deliver it on the other side at M, still more compressed. But the roller K is made (by the wheelwork) to turn round more swiftly than than ABC. The difference of velocity at the surface of the rollers is, however, very small, seldom exceeding one part in 12 or 15. But the consequence of this difference is, that the skein of cotton HI will be lengthened in the same proportion; for the upper rollers pressing on the under ones with a considerable force, their sharp flutings take good hold of the cotton between them; and since K and L take up the cotton faster than ABC and abe deliver it out, it must either be forcibly pulled through between the first rollers, or it must be stretched a little by the fibres slipping among each other, or it must break. When the extension is so very moderate as we have just now said, the only effect of it is merely to begin to draw the fibres (which at present are lying in every possible direction) into a more favourable position for the subsequent extensions.

The fibres being thus drawn together into a more favourable position, the cotton is introduced between a third pair of rollers O, P, constructed in the same way, but so moved by the wheelwork that the surface of O moves nearly or fully twice as fast as the surface of K. The roller P being also well loaded, they take a firm hold of the cotton, and the part between K and O is nearly or fully doubled in its length, and now requires a little twining to make it roundish, and to consolidate it a little.

It is therefore led floping downwards into a hole or eye in the upper pivot of the first fly, called a jack. This turns round an upright axis or spindle; the lower end of which has a pulley on it to give it motion by means of a band or belt, which passes round a drum that is turned by the machinery. This jack is of a very ingenious and complicated construction. It is a substitute for the fly of the common spinning wheel. If made precisely in the form of that fly, the thread, being so very bulky and spongy, and unable to bear close packing on the bobin, would swag out by the whirling of the fly, and would never coil up. The bobin therefore is made to lie horizontally; and this occasions the complication, by the difficulty of giving it a motion round a horizontal axis, in order to coil up the twitted roove. Mr Arkwright has accomplished this in a very ingenious manner; the essential circumstances of which we shall here briefly describe. A is a roller of hard wood, having its surface cut into sharp flutes longitudinally. On the axis, which projects through the side of the general frame, there is a pulley P, connected by a band with another pulley Q, turning with the horizontal axis QR. This axis is made to turn by a contrivance which is different in every different cotton mill. The simplest of all is to place above the pulley C (which is turned by the great band of the machinery, and thus gives motion to the jack), a thin circular disc D, loose upon the axis, so as to turn round on it without obstruction. If this disc exceed the pulley in breadth about \( \frac{1}{10} \)th of an inch, the broad belt which turns the pulley will also turn it; but as its diameter is greater than that of the pulley, it will turn somewhat slower, and will therefore have a relative motion with respect to the axis QR. This can be employed, in order to give that axis a very slow motion, such as one turn of it for 20 or 30 of the jack. This we leave to the ingenuity of the reader. The bobin B, on which the roove is to be coiled up, lies on this roller, its pivots passing through upright slits in the sides of the general frame. It lies on A, and is moved round by it, in the same manner as the uppermost of a pair of drawing rollers lies on the under one, and receives motion from it. It is evident that the fluted surface of A, by turning slowly round, and carrying the weight of the bobin, compresses a little the cotton that is between them; and its flutings, being sharp, take a flight hold of it, and cause it to turn round also, and thus coil up the roove, pulling it in through the hole E in the upper pivot (which resembles the fore pivot or eye of a spinning wheel fly) in so gentle a manner as to yield whenever the motion of the bobin is too great for the speed with which the cotton skein is discharged by the rollers O and P.—N. B. The axis QR below, also gives motion to a guide within the jack, which leads the roove gradually from one end of the bobin to the other, and back again, so as to coil it with regularity till the bobin is full. The whole of this internal mechanism of the jack is commonly shut up in a tin cylinder. This is particularly necessary when the whirling motion must be rapid, as in the second and third drawings. If open, the jacks would meet with much resistance from the air, which would load the mill with a great deal of useless work.

The reader is desired now to return to the beginning of the process, and to consider it attentively in its different stages. We apprehend that the description is sufficiently perspicuous to make him perceive the efficacy of the mechanism to execute all that is wanted, and prepare a flab that is uniform, soft, and still very extensible; in short, fit for undergoing the last treatment, by which it is made a fine and firm yarn.

As this part of the process differs from each of the former, merely by the degree of twist that is given to the yarn, and as this is given by means of a fly, not materially different from that of the spinning wheel for flax, we do not think it at all necessary to say anything more about it.

The intelligent reader is surely sensible that the yarn produced in this way must be exceedingly uniform. The uniformity really produced even exceeds all expectation; for even although there be some small inequalities in the carded fleece, yet if these are not matted clots, which the card could not equalise, and only consist of a little more thickness of cotton in some places than in others, when such a piece of the stripe comes to the first roller, it will be rather more stretched by the second, and again by the bobin, after the first very slight twining. That this may be done with greater certainty, the weights of the first rooving rollers are made very small, so that the middle part of the skein can be drawn through, while the outer parts remain fast held.

It is said that a pound of the finest Bourbon cotton has been spun into a yarn extending a few yards beyond 119 miles!

These contrivances have in some parts of Scotland been applied to the spinning of flax.

SPINNING Wheel. A very considerable improvement has been made by Mr Antis of Fulneck near Leeds of the common spinning wheel. It is well known, that hitherto much time has been lost by flopping the wheel in order to shift the thread from one staple on the flyer to another; but in Mr Antis's wheel the bobin is made to move backwards and forwards, so as to prevent the necessity of this perpetual interruption, as well as to ob- viate the danger of breaking the thread and lofing the end. This is effected by the axis of the great wheel being extended through the pillar next the spinner, and formed into a pinion of one leaf A (fig. 2.), which takes into a wheel B, seven inches diameter, having on its periphery 97 teeth; so that 97 revolutions of the great wheel cauie one of the leffer wheel. On this leffer wheel is fixed a ring of wire c c c ; which, being supported on fix legs, stands obliquely to the wheel itself, touching it at one part, and projecting nearly three quarters of an inch at the oppofite one : near the fide of this wheel is an upright lever C, about 15 inches long, moving on a centre, three inches from its lower extremity, and connected at the top to a fliding bar D ; from which rises an upright piece of brafs E, which working in the notch of a pulley drives the bobin F backward and forward, according as the oblique wire forces a pin G in or out, as the wheel moves round. To regulate and affift the alternate motion, a weight H hangs by a line to the fliding bar, and pafling over a pulley I rifes and falls as the bobin advances or recedes, and tends confantly to keep the pin in contact with the wire. It is evident, from this defcription, that one staple only is wanted to the flyer; which, being placed near the extremity K, the thread pafling through it is by the motion of the bobin laid regularly thereon. For this invention the Society instituted at London for the Encouragement of Arts, &c. gave the author a premium of 20 guineas.