360

COTTON MANUFACTURE.

The loss which the cotton suffers in the drawing frame is quite inconsiderable. Itconsists of those filaments which remain upon the drawing rollers, and collect, in agreat measure, upon the flannel facing of the top and bottom cleaner bars. It is thrownamong the top cleanings of the carding engine. When from some defect in the rollers,or negligence in piecing the running slivers, remarkably irregular portions occurin the ribands, these must.be torn off, and returned to the lap machine to be cardedanew.

The fifth operation may be called the first spinning process , as in it the cotton sliverreceives a twist; whether the twist be permanent, as in the bobbin and fly frame, or beundone immediately, as in the tube-roving machine. In fact, the elongated slivers ofparallel filaments could bear little further extension without breaking asunder, unless theprecaution were taken to condense the filaments by a slight convolution, and at the sametime to entwine them together. The twisting should positively go no further than tofulfil the purpose of giving cohesion, otherwise it would place an obstacle in the way ofthe future attenuation into level thread. The combination of drawing and twisting iswhat mainly characterizes the spinning processes, and with this fifth operation, therefore,commences the formation of yarn. As, however, a sudden extension to the wished-forfineness is not practicable, the draught is thrice repeated in machine spinning, and aftereach draught a new portion of torsion is given to the yarn, till at last it possesses thedegree of fineness and twist proportioned to its use.

The preliminary spinning process is called roving. At first the torsion is slight inproportion to the extension, since the solidity of the still coarse sliver needs that cohesive

aid only in a small degree, and loosenessof texture must be maintained to facilitateto the utmost the further elongation.

Fig. 331 is a section of the can rovingframe, the ingenious invention of Arkwright, which, till within these 14 years,v/as the principal machine for communieating the incipient torsion to the spong?cord furnished by the drawing heads. Fdiffers from that frame in nothing bn*the twisting mechanism; and consists oftwo pairs of drawing rollers, a and b 9 between which the sliver is extended in theusual way ; c are brushes for cleaning therollers; and d is the weight which pressesthe upper set upon the lower. The wipi n §covers (not shown here) rest upon # ^The surface speed of the posterior or secondpair of rollers is 3, 4, or 5 times greatsthan that of the front or receiving P air >according to the desired degree of attenua*

tion. Two drawn slivers were generally united into one by this machine’ as is shown inthe figure, where they are -seen coming from the two cans e e , to be brought together bythe pressure rollers, before they reach the drawing rollers a b. The sliver, as it escape?from these rollers, is conducted into the revolving conical lantern g, through the fun ne ^f at its top. This lantern-can receives its motion by means of a cord passing over npulley fc, placed a little way above the step on which it turns. The motion is steadiedby the collet of the funnel /, being embraced by a brass busk. Such a machine g ene 'ially contained four drawing heads, each mounted with two lanterns j in whose side thereW %, a t * 00r for out the conical coil of roving.

The motion imparted to the back roller by the band pulley or rigger m, was conveyed*°i}) e front one by toothed wheel work.

T e vertical guide pulley at bottom, n } served to lead the driving band descendingirom ine top of the frame round the horizontal whorl or pulley upon the under end 01the lantern. The operation of this can-frame was pleasing to behold: as the centrif«£ aforce serve both to distribute the soft cord in a regular coil, and also to condense a g reaea o l mos gently within a moderate space. Whenever the lantern was filled;ten er ‘ ca ^ ri ^ ie roving t 0 a simple machine, where it was wound upon bobbins yhand. NotwHhstandmg every care in this transfer, the delicate texture was very aptthe serious "Jj , ? so as 10 cause corresponding injuries in every subsequent °l’® r “ i a rand in the finished yarn. Messrs. Cocker and Higsins, of Salford , had the mb*” 1 "?merit, as I have said, of superseding that beautiful but defective mechanism, wblch .!L.held a prominent place m uU cotton mills from almost the infancy of the factory system,by the following apparatus.

The Bobbin and Fly frame is now the great roving machine of the cotton manufac-