82 TECHNOLOGY. 
In the middle of each of the top rollers, a’ 5’ c', are smooth necks supporting 
composition-boxes, ¢ and f, upon which are suspended weights, g and g', by 
means of wires, 4 and h’ (figs. 19, 20). Generally the two back rollers, 
which move the slowest, are pressed down by a common weight, whilst the 
front roller has a separate weight. 
The three other rollers are covered with a bar of mahogany, ¢, which is 
covered underneath with flannel, and wipes off any fibres left remaining 
upon the surface of the roller. A. corresponding bar, 6, about one inch 
thick, and covered upon its upper surface with flannel, of the length of the 
drawing-roller, is pressed against the under side of the two forward rollers, 
6 and c, by means of the small weight m. This bar also serves to keep the 
forward rollers free of fibres. The cord or wire upon which m hangs goes 
over the roller e, and then down again, in order to support the wiper bar J. 
In jigs. 17 and 19, a represents a smooth curved plate of brass, with 
curved channels upon its surface, which conduct the slivers nm from their 
respective cans, H, at the back of the machine to the drawing-rollers. The 
slivers are kept apart by the pins o in the brass rod p. In this manner 
three to six slivers are united upon each division of the fluted rollers, and 
are extended by the drawing-rollers, particularly the front pair, into one 
thin, uniform, and much elongated sliver. Generally two such slivers are 
conducted through a funnel, 1, and pass off through the smooth rollers x 
into the cans L. 
The motions of the machine are as follows: n is the usual fast-and-loose 
pulley on the prolongation of the shaft of the lower forward drawing-roller ; 
this pulley is driven by a band from the pulley p upon the shaft c; upon 
the same front roller shaft is also a pinion, which, by means of the inter- 
mediate wheel 2, drives the wheel 3 upon the end of the smooth roller x 
(pl. 17, fig. 18). Upon the other end of the forward fluted roller ¢ is a 
pinion, which drives the shaft o by means of the wheel 5. By the side of 
the latter wheel and upon the same shaft is another small wheel, 6, which 
drives a larger wheel, 7, upon the prolongation of the lower middle roller b. 
Upon the other end of the shaft o is the wheel 8, which engages with a 
wheel, 9, upon the back lower roller a. 
Having examined the operation of the drawing-frame, we will notice 
more closely the changes brought about upon the fibres of the cotton. Were 
the surface velocities of the three rollers abc equal, the slivers nn would 
pass through the machine unaltered. As, however, the velocity of 6 and ¢ 
is greater than that of a, the former will deliver a greater length of riband 
than they receive from the latter, or than this receives from the cans #, and 
there results, in consequence, an extension of the riband between the rollers 
a, b, and c, and a proportional approach to parallelism in the fibres during 
the process. The distances between the drawing-rollers, a, b, and c, are so 
adjusted to the staple of the cotton that no disruption of the fibres will take 
place, which must inevitably occur if the length of the individual fibres 
were less than the distance between the rollers. 
It would be impossible to continue the drawing upon a single sliver until 
the requisite parallelism of fibre were attained, on account of the excessive 
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