Teasling

—The object of this operation is to raise up the loose filaments of the woollen yarn into a nap upon one of the surfaces of the cloth, by scratching it either with thistle-heads, called teasels, or with teasling-cards or brushes, made of wire. The natural teasels are the balls which contain the seeds of the plant called Dipsacus fullorum ; the scales which form the balls, project on all sides, and end in sharp elastic points, that turn downwards like hooks. In teasling by hand, a number of these balls are put into a small wooden frame, having cro ed handles, eight or ten inches long; and when thus filled, form an implement not unlike a curry-comb, which is used by two men, who seize the teasel-frame by the handles, and scrub the face of the cloth, hung in a vertical position from two horizontal rails, made fast to the ceiling of the workshop. First, they wet the cloth, and work three times over, by strokes in the direction of the warp, and next of that of the weft, so as to raise all the loose fibres from the felt, and to prepare it for shearing. In large manufactories, this dre ing operation is performed by a machine called a gig-mill, which originally consisted, and in most places still consists, of a cylinder bristled all over with the thistle-heads, and made to revolve rapidly while the cloth is drawn over it in a variety of directions. If the thistle be drawn in the line of the warp, the points act more efficaciously upon the weft, being perpendicular to its softer spun yarns. Inventors who have tried to give the points a circular or oblique action between the warp and the weft, proceed apparently upon a false principle, as if the cloth were like a plate of metal, whose substance could be pushed in any direction. Teasling really consists in drawing out one end of the filaments, and leaving the body of them entangled in the cloth; and it should seize and pull them perpendicularly to their length, because in this way it acts upon the ends, which being least implicated, may be most readily disengaged. When the hooks of the thistles become clogged with flocks of wool, they must be taken out of the frame or cylinder, and cleaned by children with a small comb. Moisture, moreover, softens their points, and impairs their teasling powers; an effect which needs to be counterbalanced, by taking them out, and drying them from time to time. Many contrivances have, therefore, been proposed, in which metallic teasels of an unchangeable nature, mounted in rotatory machines, driven by power, have been substituted for the vegetable, which being required in prodigious quantities, become sometimes exce ively scarce and dear in the clothing districts. In 1818, several schemes of that kind were patented in France, of which those of M. Arnold-Merick, and of MM. Taurin frères, of Elbœuf, are described in the 16th volume of Brevets d’Invention expirés . Mr. Daniell, cloth manufacturer in Wilts, renewed this invention under another form, by making his rotatory cards with two kinds of metallic wires, of unequal lengths; the one set, long, thin, and delicate, representing the points of the thistle; the other, shorter, stiffer, and blunter, being intended to stay the cloth, and to hinder the former from entering too far into it. But none of these proce es have succeeded in discarding the natural teasel from the most eminent manufactories. The French government purchased, in 1807, the patent of Douglas, an English mechanist, who had, in 1802, imported into France, the best system of gig-mills then used in the west of England. A working set of his machines having been placed in the Conservatoire des Arts , for public inspection, they were soon introduced into most of the French establishments, so as generally to supersede teasling ( lainage ) by hand. A description of them was published in the third volume of the Brevets d’Invention . The following is an outline of some subsequent improvements :— 1. As it was imagined that the seesaw action of the hand operative was in some respects more effectual than the uniform rotation of a gig-mill, this was attempted to be imitated by an alternating movement. 2. Others conceived that the seesaw motion was not e ential, but that it was advantageous to make the teasels or cards act in a rectilinear direction, as in working by hand; this action was attempted by placing the two ends of the teasel-frame in grooves formed like the letter D , so that the teasel should act on the cloth only when it came into the rectilinear part. Mr. Wells, machine-maker, of Manchester, obtained a patent, in 1832, for this construction. 3. It was supposed that the teasels should not act perpendicularly to the weft, but obliquely or circularly upon the face of the cloth. Mr. Ferrabee, of Gloucester, patented, in 1830, a scheme of this kind, in which the teasels are mounted upon two endle chains, which traverse from the middle of the web to the selvage or list, one to the right, and another to the left hand, while the cloth itself pa es under them with such a velocity, that the effect, or resultant , is a diagonal action, dividing into two equal parts the rectangle formed by the weft and warp yarns. Three patent machines of Mr. George Oldland—the first in 1830, the second and third in 1832—all proceed upon this principle. In the first, the teasels are mounted upon discs made to turn flat upon the surface of the cloth; in the second, the rotating discs are pre ed by corkscrew spiral springs against the cloth, which is supported by an elastic cushion, also pre ed against the discs by springs; and in the third machine, the revolving discs have a larger diameter, and they turn, not in a horizontal, but a vertical plane. 4. Others fancied that it would be beneficial to support the reverse side of the cloth by flat hard surfaces, while acting upon its face with cards or teasels. Mr. Joseph Cliseld Daniell, having stretched the cloth upon smooth level stones, teasels them by hand. 5. Me rs. Charles worth and Mellor obtained a patent, in 1829, for supporting the back of the cloth with elastic surfaces, while the part was exposed to the teasling action. 6. Elasticity has also been imparted to the teasels, in the three patent inventions of Mr. Sevill, Mr. J. C. Daniell, and Mr. R. At kins on. 7. It has been thought useful to separate the teasel-frames upon the drum of the gig-mill, by simple rollers, or by rollers heated with steam, in order to obtain the combined effect of calendering and teasling. Mr. J. C. Daniell, Mr. G. Haden, and Mr. J. Rayner, have obtained patents for contrivances of this kind. 8. Several French schemes have been mounted for making the gig-drum act upon the two sides of the cloth, or even to mount two drums on the same machine. Mr. Jones, of Leeds, contrived a very excellent method of stretching the cloth, so as to prevent the formation of folds or wrinkles. (See Newton’s Journal, vol. viii., 2nd series, page 126.) Mr. Collier, of Paris, obtained a patent, in 1830, for a greatly improved gig-mill, upon Douglas’s plan, which is now much esteemed by the French clothiers. The following figures and description exhibit one of the latest and best teasling machines. It is the invention of M. Dubois and Co., of Louviers, and is now doing excellent work in that celebrated seat of the cloth manufacture. In the fulling-mill, the woollen web acquires body and thickne , at the expense of its other dimensions; for being thereby reduced about one-third in length, and one-half in breadth, its surface is diminished to one-third of its size as it comes out of the loom; and it has, of course, increased threefold in thickne . As the filaments drawn forth by teasling, are of very unequal lengths, they must be shorn to make them level, and with different degrees of closene , according to the quality of the stuff, and the appearance it is desired to have. But, in general, a single operation of each kind is insufficient; whence, after having pa ed the cloth once through the gig-mill, and once through the shearing-machine ( tondeuse ), it is ready to receive a second teasling, deeper than the first, and then to suffer a second shearing. Thus, by the alternate repetition of these proce es, as often as is deemed proper, the cloth finally acquires its wished-for appearance. Both of these operations are very delicate, especially the first; and if they be ill conducted, the cloth is weakened, so as to tear or wear most readily. On the other hand, if they be skilfully executed, the fabric becomes not only more sightly, but it acquires strength and durability, because its face is changed into a species of fur, which protects it from friction and humidity. IMG:4147767755307473660_illo1321.png:Gig-mill Figs. 1214 and 1215 enlarged (271 kB) Figs. 1214 , 1215. , represent the gig-mill in section, and in front elevation. A , B , C , D , A ′, B ′, C ′, D ′, being the strong frame of iron, cast in one piece, having its feet enlarged a little more to the inside than to the outside, and bolted to large blocks in the stone pavement. The two uprights are bound together below by two cro -beams A ′′, being fastened with screw-bolts at the ears a′ ′ , a′ ′ ; and at top, by the wrought-iron stretcher-rod D , whose ends are secured by screw-nuts at D , D ′. The drum is mounted upon a wrought-iron shaft F , which bears at its right end ( fig. 1215. ), exterior to the frame, the usual riggers, or fast and loose pulley, f f′ ′ , f′ , which give motion to the machine by a band from the main shaft of the mill. On its right end, within the frame, the shaft F , has a bevel wheel F ′, for transmitting movement to the cloth, as shall be afterwards explained. Three crown wheels G , of which one is shown in the section, fig. 1214. , are, as usual, keyed by a wedge to the shaft F . Their contour is a sinuous band, with six semi-cylindrical hollows, separated alternately by as many portions of the periphery. One of these three wheels is placed in the middle of the shaft F , and the other two, towards its extremities. Their size may be judged of, from inspection of fig. 1214. After having set them so that all their spokes or radii correspond exactly, the 16 sides H , are made fast to the 16 portions of the periphery, which correspond in the three wheels. These sides are made of sheet iron, curved into a gutter form, fig. 1214. , but rounded off at the end, fig. 1215. , and each of them is fixed to the three felloes of the wheels by three bolts h . The elastic part of the plate iron allows of their being sufficiently well adjusted, so that their flat portions furthest from the centre may lie pretty truly on a cylindrical surface, whose axis would coincide with that of the shaft F . IMG:4147767755307473660_illo1322.png:Frame and clamps Between the 16 sides there are 16 intervals, which correspond to the 16 hollo wings of each of the wheels. Into these intervals are adjusted, with proper precautions, 16 frames bearing the teasels which are to act upon the cloth. These are fitted in as follows:—Each has the shape of a rectangle, of a length equal to that of the drum, but their breadth only large enough to contain two thistle-heads set end to end, thus making two rows of parallel teasels throughout the entire length, (see the contour in fig. 1214. ) A portion of the frame is represented in fig. 1216. The large side I , against which the tops of the teasels rest, is hollowed out into a semi-cylinder, and its opposite side is cleft throughout its whole length, to receive the tails of the teasels, which are seated and compre ed in it. There are, moreover, cro -bars i , which serve to maintain the sides of the frame I , at an invariable distance, and to form short compartments for keeping the thistles compact. The ends are fortified by stronger bars k , k , with projecting bolts to fasten the frames between the ribs. The distance of the sides of the frame I , I ′, ought to be such, that if a frame be laid upon the drum, in the interval of two ribs, the side I will rest upon the inclined plane of one of the ribs, and the side I ′ upon the inclined plane of the other, (see fig. 1214. ); while at the same time the bars k , of the two ends of the frame, rest upon the flat parts of the ribs themselves. This point being secured, it is obvious, that if the ends of the bars k be stopped, the frame will be made fast. But they need not be fixed in a permanent manner, because they must be frequently removed and replaced. They are fastened by the clamp, ( figs. 1217 , 1218. ), which is shut at the one end, and furnished at the other with a spring, which can be opened or shut at pleasure. 2 and 4, in fig. 1215. (near the right end of the shaft F ), shows the place of the clamp, figs. 1217 , 1218. The bar of the right hand is first set in the clamp, by holding up its other end; the frame is then let down into the left-hand clamp. The cloth is wound upon the lower beam Q , fig. 1214. ; thence it pa es in contact with a wooden cylinder T , turning upon an axis, and proceeds to the upper beam P , on to which it is wound: by a contrary movement, the cloth returns from the beam P to Q , over the cylinder T ; and may thus go from the one to the other as many times as shall be requisite. In these succe ive circuits it is presented to the action of the teasels, under certain conditions. In order to be properly teasled, it must have an equal tension throughout its whole breadth during its traverse; it must be brought into more or le close contact with the drum, according to the nature of the cloth, and the stage of the operations; sometimes being a tangent to the surface, and sometimes embracing a greater or smaller portion of its contour, it must travel with a determinate speed, dependent upon the velocity of the drum, and calculated so as to produce the best result: the machine itself must make the stuff pa alternately from one winding beam to the other. In fig. 1215. , before the front end of the machine, there is a vertical shaft L , as high as the framework, which revolves with great facility, in the bottom step l , the middle collet l′ , and top collet l′ ′ , in the prolongation of the stretcher D . Upon this upright shaft are mounted—1. a bevel wheel L ′; 2. an upper bevel pinion M , with its bo M ′; 3. a lower bevel pinion N , with its bo N ′. The bevel wheel L ′ is keyed upon the shaft L , and communicates to it the movement of rotation which it receives from the pinion f , with which it is in geer; but the pinion f , which is mounted upon the shaft F of the drum, participates in the rotation which this shaft receives from the prime mover, by means of the fast rigger-pulley f′ . The upper pinion M is independent upon the shaft L ; that is to say, it may be slidden along it, up and down, without being driven by it; but it may be turned in an indirect manner by means of six curved teeth, projecting from its bottom, and which may be rendered active or not, at pleasure; these curved teeth, and their intervals, correspond to similar teeth and intervals upon the top of the bo M ′, which is dependent, by feathered indentations, upon the rotation of L , though it can slide freely up and down upon it. When it is raised, therefore, it comes into geer with M . The pinion N , and its bo , have a similar mode of being thrown into and out of geer with each other. The bo es M ′ and N ′, ought always to be moved simultaneously, in order to throw one of them into geer, and the other out of geer. The shaft L serves to put the cloth in motion, by means of the bevel wheels P ′′ and Q ′′, upon the ends of the beams P , Q , which take into the pinions M and N . The mechanism destined to stretch the cloth is placed at the other end of the machine, where the shafts of the beams P , Q , are prolonged beyond the frame, and bear at their extremities P ′ and Q ′, armed each with a brake. The beam P ( fig. 1214. ), turns in an opposite direction to the drum; consequently the cloth is wound upon P , and unwound from Q . If, at the same time as this is going on, the handle R ′, of the brake-shaft, be turned so as to clasp the brake of the pulley Q ′, and release that of the pulley P ′, it is obvious that a greater or smaller resistance will be occasioned in the beam Q , and the cloth which pulls it in unwinding, will be able to make it turn only when it has acquired the requisite tension; hence it will be nece ary, in order to increase or diminish the tension, to turn the handle R ′ a little more or a little le in the direction which clasps the brake of the pulley Q ′; and as the brake acts in a very equable manner, a very equable tension will take place all the time that the cloth takes to pa . Besides, should the diminution of the diameter of the beam Q , render the tension le efficacious in any considerable degree, the brake would need to be unclamped a very little, to restore the primitive tension. When the cloth is to be returned from the beam P , to the beam Q , Z must be lowered, to put the shaft L out of geer above, and in geer below; then the cloth-beam Q , being driven by that vertical shaft, it will turn in the same direction as the drum, and will wind the cloth round its surface. In order that it may do so, with a suitable tension, the pulley Q ′ must be left free, by clasping the brake of the pulley P ′, so as to oppose an adequate resistance. The cloth is brought into more or le close contact with the drum as follows:—There is for this purpose a wooden roller T , against which it pre es in pa ing from the one winding beam to the other, and which may have its position changed relatively to the drum. It is obvious, for example, that in departing from the position represented in fig. 1214. , where the cloth is nearly a tangent to the drum, if the roller T ′ be raised, the cloth will cease to touch it; and if it be lowered, the cloth will, on the contrary, embrace the drum over a greater or le portion of its periphery. For it to produce these effects, the roller is borne at each end, by iron gudgeons, upon the heads of an arched rack T ′′ ( fig. 1214. ), where it is held merely by pins. These racks have the same curvature as the circle of the frame, against which they are adjusted by two bolts; and by means of slits, which these bolts traverse, they may be slidden upwards or downwards, and consequently raise or depre the roller T . But to graduate the movements, and to render them equal in the two racks, there is a shaft U , supported by the uprights of the frame, and which carries, at each end, pinions U ′, U ′′, which work into the two racks T ′, T ′′: this shaft is extended in front of the frame, upon the side of the head of the machine ( fig. 1215. ), and there it carries a ratchet wheel u , and a handle u′ . The workman, therefore, requires merely to lay hold of the handle, and turn it in the direction of the ratchet wheel, to raise the racks, and the roller T , which they carry; or to lift the click or catch, and turn the handle in the opposite direction, when he wishes to lower the roller, so as to apply the cloth to a larger portion of the drum. CLOTH CROPPING. Of machines for cropping or shearing woollen cloths, those of Lewis and Davis have been very generally used. Fig. 1219. is an end view, and fig. 1220. is a side view, of Lewis’s machine, for shearing cloth from list to list. Fig. 1221. is an end view of the carriage, with the rotatory cutter detached from the frame of the machine, and upon a larger scale: a , is a cylinder of metal, on which is fixed a triangular steel wire; this wire is previously bent round the cylinder in the form of a screw, as represented at a , a , in fig. 1219. , and, being hardened, is intended to constitute one edge of the shear or cutter. IMG:4147767755307473660_illo1324a.png:Cloth shearing machine IMG:4147767755307473660_illo1324b.png:Carriage and plates The axis of the cylindrical cutter a , turns in the frame b , which, having proper adjustments, is mounted upon pivots c , in the standard of the travelling carriage d , d ; and e , is the fixed or ledger blade, attached to a bar f , which constitutes the other edge of the cutter; that is, the stationary blade, against which the edges of the rotatory cutter act; f and g , are flat springs, intended to keep the cloth (shown by dots) up against the cutting edges. The form of these flat springs f , g , is shown at figs. 1222. and 1223. , as consisting of plates of thin metal cut into narrow slips ( fig. 1222. ), or perforated with long holes, ( fig. 1223. ) Their object is to support the cloth, which is intended to pa between them, and operate as a spring bed, bearing the surface of the cloth against the cutters, so that its pile or nap may be cropped off or shorn as the carriage d is drawn along the top rails of the standard or frame of the machine h , h , by means of cords. The piece of cloth to be shorn, is wound upon the beam k , and its end is then conducted through the machine, between the flat springs f and g (as shown in fig. 1221. ), to the other beam l , and is then made fast; the sides or lists of the cloth being held and stretched by small hooks, called habiting hooks. The cloth being thus placed in the machine, and drawn tight, is held distended by means of ratchets on the ends of the beams k and l , and palls. In commencing the operation of shearing, the carriage d , must be brought back, as in fig. 1221. , so that the cutters shall be close to the list; the frame of the cutters is raised up on its pivots as it recedes, in order to keep the cloth from injury, but is lowered again previously to being put in action. A band or winch is applied to the rigger or pulley m , which, by means of an endle cord pa ed round the pulley n , at the reverse end of the axle of m , and round the other pulleys o and p , and the small pulley q , on the axle of the cylindrical cutter, gives the cylindrical cutter a very rapid rotatory motion; at the same time a worm, or endle screw, on the axle of m and n , taking into the teeth of the large wheel r , causes that wheel to revolve, and a small drum s , upon its axle, to coil up the cord, by which the carriage d , with the cutters a and e , and the spring bed f and g , are slowly, but progre ively, made to advance, and to carry the cutters over the face of the cloth, from list to list; the rapid rotation of the cutting cylinder a , producing the operation of cropping or shearing the pile. Upon the cutting cylinder, between the spiral blades, it is proposed to place stripes of plush, to answer the purpose of brushes, to raise the nap or pile as the cylinder goes around, and thereby a ist in bringing the points of the wool up to the cutters. The same contrivance is adapted to a machine for shearing the cloth lengthwise. IMG:4147767755307473660_illo1325.png:Shearing machine Fig. 1224. is a geometrical elevation of one side of Mr. Davis’s machine. Fig. 1225. a plan or horizontal representation of the same, as seen in the top; and fig. 1226. a section taken vertically acro the machine near the middle, for the purpose of displaying the working parts more perfectly than in the two preceding figures. These three figures represent a complete machine in working condition, the cutters being worked by a rotatory motion, and the cloth so placed in the carriage as to be cut from list to list. a , a , a , is a frame or standard, of wood or iron, firmly bolted together by cro braces at the ends and in the middle. In the upper side-rails of the standard, there is a series of axles carrying anti-friction wheels b , b , b , upon which the side-rails c , c , of the carriage or frame that bears the cloth runs, when it is pa ing under the cutters in the operation of shearing. The side-rails c , c , are straight bars of iron, formed with edges v , on their under sides, which run smoothly in the grooves of the rollers b , b , b . These side-rails are firmly held together by the end stretchers d , d . The sliding frame has attached to it the two lower rollers e , e , upon which the cloth intended to be shorn is wound; the two upper lateral rollers f , f , over which the cloth is conducted and held up; and the two end rollers g , g , by which the habiting rails h , h , are drawn tight. In preparing to shear a piece of cloth, the whole length of the piece is, in the first place, tightly rolled upon one of the lower rollers e , which must be something longer than the breadth of the cloth from list to list. The end of the piece is then raised, and pa ed over the top of the lateral rollers f , f , whence it is carried down to the other roller e , and its end or farral is made fast to that roller. The hooks of the habiting rails h , h , are then put into the lists, and the two lower rollers e , e , with the two end rollers g , g , are then turned, for the purpose of drawing up the cloth, and straining it tight, which tension is preserved by ratchet wheels attached to the ends of the respective rollers, with palls dropping into their teeth. The frame carrying the cloth, is now slidden along upon the top standard rails by hand, so that the list shall be brought nearly up to the cutter i , i , ready to commence the shearing operation; the bed is then raised, which brings the cloth up against the edges of the shears. IMG:4147767755307473660_illo1326a.png:Shearing machine The construction of the bed will be seen by reference to the cro section fig. 1226. It consists of an iron or other metal roller k , k , turned to a truly cylindrical figure, and covered with cloth or leather, to afford a small degree of elasticity. This roller is mounted upon pivots in a frame l , l , and is supported by a smaller roller m , similarly mounted, which roller m , is intended merely to prevent any bending or depre ion of the central part of the upper roller or bed k , k , so that the cloth may be kept in close contact with the whole length of the cutting blades. In order to allow the bed k to rise and fall, for the purpose of bringing the cloth up to the cutters to be shorn, or lowering it away from them after the operation, the frame l , l , is made to slide up and down in the grooved standard n , n , the movable part enclosed within the standard being shown by dots. This standard n , is situated about the middle of the machine, cro ing it immediately under the cutters, and is made fast to the frame a , by bolts and screws. There is a lever o , attached to the lower cro -rail of the standard, which turns upon a fulcrum-pin, the extremity of the shorter arm of which lever acts under the centre of the sliding-frame, so that by the lever o , the sliding-frame, with the bed, may be raised or lowered, and when so raised, be held up by a spring catch j . IMG:4147767755307473660_illo1326b.png:Details of cutters It being now explained by what means the bed which supports the cloth is constructed, and brought up, so as to keep the cloth in close contact with the cutters, while the operation of shearing is going on; it is nece ary, in the next place, to describe the construction of the cutters, and their mode of working; for which purpose, in addition to what is shown in the first three figures, the cutters are also represented detached, and upon a larger scale, in fig. 1227. In this figure is exhibited a portion of the cutters in the same situation as in fig. 1221. ; and alongside of it is a section of the same, taken through it at right angles to the former; p , is a metallic bar or rib, somewhat of a wedge form, which is fastened to the top part of the standard a , a , seen best in fig. 1220. To this bar a straight blade of steel g , is attached by screws, the edge of which stands forward even with the centre or axis of the cylindrical cutter i , and forms the ledger blade, or lower fixed edge of the shears. This blade remains stationary, and is in close contact with the pile or nap of the cloth, when the bed k , is raised, in the manner above described. The cutter or upper blade of the shears, is formed by inserting two or more strips of plate steel r , r , in twisted directions, into grooves in the metallic cylinder i , i , the edges of which blades r , as the cylinder i revolves, traverse along the edge of the fixed or ledger blade g , and by their obliquity produce a cutting action like shears; the edges of the two blades taking hold of the pile or raised nap, as the cloth pa es under it, shaves off the superfluous ends of the wool, and leaves the face smooth. Rotatory motion is given to the cutting cylinder i , by means of a band leading from the wheel s , which pa es round the pulley fixed on the end of the cylinder i , the wheel s being driven by a band leading from the rotatory part of a steam-engine, or any other first mover, and pa ed round the rigger t , fixed on the axle s . Tension is given to this band by a tightening pulley u , mounted on an adjustable sliding-piece v , which is secured to the standard by a screw; and this rigger is thrown in and out of geer by a clutch-box and lever, which sets the machine going, or stops it. In order to give a drawing stroke to the cutter, which will cause the piece of cloth to be shorn off with better effect, the upper cutter has a slight lateral action, produced by the axle of the cutting cylinder being made sufficiently long to allow of its sliding laterally about an inch in its bearings; which sliding is effected by a cam w , fixed at one end. This cam is formed by an oblique groove, cut round the axle, (see w , fig. 1227. ) and a tooth x , fixed to the frame or standard which works in it, as the cylinder revolves. By means of this tooth, the cylinder is made to slide laterally, a distance equal to the obliquity of the groove w , which produces the drawing stroke of the upper shear. In order that the rotation of the shearing cylinder may not be obstructed by friction, the tooth x , is made of two pieces, set a little apart, so as to afford a small degree of elasticity. The manner of pa ing the cloth progre ively under the cutters is as follows:—On the axle of the wheel s , and immediately behind that wheel, there is a small rigger, from which a band pa es to a wheel y , mounted in an axle turning in bearings on the lower side-rail of the standard a . At the reverse extremity of this axle, there is another small rigger 1, from which a band pa es to a wheel 2, fixed on the axle 3, which cro es near the middle of the machine, seen in fig. 1226. Upon this axle there is a sliding pulley 4, round which a cord is pa ed several times, whose extremities are made fast to the ends of the sliding carriage d ; when, therefore, this pulley is locked to the axle, which is done by a clutch box, the previously described movements of the machine cause the pulley 4 to revolve, and by means of the rope pa ed round it, to draw the frame, with the cloth, slowly and progre ively along under the cutters. It remains only to point out the contrivance whereby the machinery throws itself out of geer, and stops its operations, when the edge of the cloth or list arrives at the cutters. At the end of one of the habiting rails h , there is a stop affixed by a nut and screw 5, which, by the advance of the carriage, is brought up and made to pre against a lever 6; when an arm from this lever 6, acting under the catch 7, raises the catch up, and allows the hand-lever 8, which is pre ed upon by a strong spring, to throw the clutch-box 10, out of geer with the wheel 8; whereby the evolution of the machine instantly ceases. The lower part of the lever 6, being connected by a joint to the top of the lever j , the receding of the lever 6, draws back the lower catch j , and allows the sliding frame l , l , within the bed k , to descend. By now turning the lower rollers e , e , another portion of the cloth is brought up to be shorn; and when it is properly habited and strained, by the means above described, the carriage is slidden back, and, the parts being all thrown into geer, the operation goes on as before. Mr. Hirst’s improvements in manufacturing woollen cloths, for which a patent was obtained in February, 1830, apply to that part of the proce where a permanent lustre is given usually by what is called roll-boiling; that is, stewing the cloth, when tightly wound upon a roller, in a ve el of hot water or steam. As there are many disadvantages attendant upon the operation of roll-boiling, such as injuring the cloths, by overheating them, which weakens the fibre of the wool, and also changes some colours, he substituted, in place of it, a particular mode of acting upon the cloths, by occasional or intermitted immersion in hot water, and also in cold water, which operations may be performed either with or without pre ure upon the cloth, as circumstances may require. IMG:4147767755307473660_illo1327.png:Roll-boiling apparatus The apparatus which he proposes to employ for carrying on his improved proce , is shown in the accompanying drawing. Fig. 1228. is a front view of the apparatus, complete, and in working order; fig. 1229. is a section, taken transversely through the middle of the machine, in the direction of fig. 1230. ; and fig. 1230. is an end view of the same; a , a , a , is a ve el or tank, made of iron or wood, or any other suitable material: sloping at the back and front, and perpendicular at the ends. This tank must be sufficiently large to admit of half the diameter of the cylinder or drum b , b , b , being immersed into it, which drum is about four feet diameter, and about six feet long, or something more than the width of the piece of cloth intended to be operated upon. This cylinder or drum b , b , is constructed by combining segments of wood cut radially on their edges, secured by screw-bolts to the rims of the iron wheels, having arms, with an axle pa ing through the middle. The cylinder or drum being thus formed, rendered smooth on its periphery, and mounted upon its axle in the tank, the piece of cloth is wound upon it as tightly as po ible, which is done by placing it in a heap upon a stool, as at c , fig. 1229. , pa ing its end over and between the tension-rollers d , e , and then securing it to the drum, the cloth is progre ively drawn from the heap, between the tension-rollers, which are confined by a pall and ratchet, on to the periphery of the drum, by causing the drum to revolve upon its axis, until the whole piece of cloth is tightly wound upon the drum; it is then bound round with canvas or other wrappers, to keep it secure. If the tank has not been previously charged with clean and pure water, it is now filled to the brim, as shown at fig. 1229. , and opening the stopcock of the pipe f , which leads from a boiler, the steam is allowed to blow through the pipe, and discharge itself at the lower end, by which means the temperature of the water is raised in the tank to about 170° Fahr. Before the temperature of the water has got up, the drum is set in slow rotatory motion, in order that the cloth may be uniformly heated throughout; the drum making about one rotation per minute. The cloth, by immersion in the hot water, and pa ing through the cold air, in succe ion, for the space of about eight hours, gets a smooth soft face, the texture not being rendered harsh, or otherwise injured, as is frequently the case by roll-boiling. Uniform rotatory motion to the drum is shown in fig. 1228. , in which g is an endle screw or worm, placed horizontally, and driven by a steam-engine or any other first mover employed in the factory. This endle screw takes into the teeth of, and drives, the vertical wheel h , upon the axle of which the coupling-box i , i , is fixed, and, consequently, continually revolves with it. At the end of the shaft of the drum, a pair of sliding clutches k , k , are mounted, which, when projected forward, as shown by dots in fig. 1228. , produce the coupling or locking of the drum-shaft to the driving wheel, by which the drum is put in motion; but on withdrawing the clutches k , k , from the coupling-box i , i , as in the figure, the drum immediately stands still. After operating upon the cloth in the way described, by pa ing it through hot water for the space of time required, the hot water is to be withdrawn by a cock at the bottom, or otherwise, and cold water introduced into the tank in its stead; in which cold water the cloth is to be continued turning, in the manner above described, for the space of twenty-four hours, which will perfectly fix the lustre that the face of the cloth has acquired by its immersion in the hot water, and leave the pile or nap, to the touch, in a soft silky state. In the cold-water operation he sometimes employs a heavy pre ing roller l , which, being mounted in slots in the frame or standard, revolve with the large drum, rolling over the back of the cloth as it goes round. This roller may be made to act upon the cloth with any required pre ure, by depre ing the screws m , m , or by the employment of weighted levers, if that should be thought nece ary.