Linen and Linen Manufactures

The preparation of tow for spinning differs in essential features from the processes above described. Tow from different sources, such as scutching tow, hackle tow, etc., differs considerably in quality and value, some being very impure, filled with woody shives, etc., whereas other kinds are comparatively open and clean. A preliminary opening and cleaning is necessary for the dirty, much-matted tows, and in general thereafter they are passed through two carding engines called respectively the breaker and the finisher cards till the slivers from their processes are ready for the drawing and roving frames. In the case of fine clean tows, on the other hand, passing through a single carding engine may be sufficient. The processes which follow the carding do not differ materially from those followed in the preparation of rove from line flax.

Spinning.

The spinning operation, which follows the roving, is done in two principal ways, called respectively dry spinning and wet spinning; the first being used for the lower counts or heavier yarns, while the second is exclusively adopted in the preparation of fine yarns. There is also a demi-sec method of spinning em ployed in some mills. The spinning frame does not differ in prin ciple from the throstle spinning machine used in cotton manufac ture. The bobbins of flax rove are arranged in rows on each side of the frame (the spinning frames being all double) on pins in an inclined plane. The rove passes downwards through an eyelet or guide to a pair of nipping or retaining rollers between which and the final drawing rollers, placed in the case of dry spinning from s8in. to 22in. lower down, the fibre receives its final draft while passing over and under cylinders and guide-plate, and attains that degree of tenuity which the finished yarn must possess. From the last rollers the now attenuated material, in passing to the flyers, receives the degree of twist which compacts the fibres into the round hard cord which constitutes spun yarn ; and from the flyers it is wound on the more slowly rotating spool within the flyer arms, centred on the top of the spindle. The amount of twist given to the thread at the spinning frame varies from 1.5 to 2 times the square root of the count. In wet spinning the general sequence of operations is the same, but the rove, as unwound from its bobbin, first passes through a trough of water heated to about s5o° F. ; and the interval between the two pairs of rollers in which the drawing out of the rove is accomplished is very much shorter. The influence of the hot water on the flax fibre appears

to be that it softens the gummy substance which binds th6 ultimate fibres together, and thereby allows these fibres to a certain extent to be drawn out without breaking the continuity of the fibre; and further it makes a finer, smoother and more uniform strand than can be obtained by dry spinning. The extent to which the original strick of flax as laid on the feeding roller for (say) the production of a 5o lea yarn is by doublings and drawings extended, when it reaches the spinning spindle, may be stated thus : 35 times on spreading frame, 15 times on first drawing frame, 15 times on sec ond drawing frame, 14 times on third drawing frame, 15 times on roving frame and so times on spinning frame, in all 16,537,500 times its original length, with 8 X 12 X 16 = 1,536 doublings on the three drawing frames. That is to say, 'yd. of hackled line fed into the spreading frame is spread out, mixed with other fibres, to a length of about 9,400m. of yarn, when the above drafts obtain. The drafts are much shorter for the majority of yarns.

The next operation is reeling from the bobbins into hanks. By act of parliament, throughout the United Kingdom the standard measure of flax yard is the "lea," called also in Scotland the "cut" of 30o yards. The flax is wound or reeled on a reel having a cir cumference of 9oin. (21yd.) making "a thread," and 120 such threads form a lea. The grist or count of all fine yarns is esti mated by the number of leas in sib.; thus "so lea" indicates that there are 5o leas or cuts of 3ooyd. each in i lb. of the yarn so denominated. With the heavier yarns in Scotland the quality is indicated by their weight per "spyndle" of 48 cuts or leas; thus "3 lb. tow yarn" is such as weighs 3 lb. per spyndle, equivalent to "16 lea," because jute count X lea count = 48 .• .31-3- lea = 3 lb. per spyndle.

The hanks of yarn from wet spinning are either dried in a loft with artificial heat in one of the many modern hank-drying ma chines or exposed over ropes in the open air. When dry they are twisted back and forward to take the wiry feeling out of the yarn, and made up in bundles for the market as "grey yarn." English spinners make up their yarns into "bundles" of 20 hanks, each hank containing io leas; Irish spinners make hanks of 12 leas, 164 of which form a bundle; Scottish manufacturers adhere to the spyndle containing 4 hanks of 12 cuts or leas.