Page:Encyclopædia Britannica, Ninth Edition, v. 14.djvu/689

 LINEN 665 broken, ravelled, and short fibres, which separate out in the heckling process, form tow, an article of much inferior value to the spinner; and the proportion of tow made in the process of hand-heckling varies according to the skill and knowledge of the heckler. A good deal of baud-heck ling is still practised, especially in Irish and Continental factories ; and it has not been found practicable, in any case, to entirely dispense with a rough preparation of the fibre by hand labour. In heckling by hand, the heckler stakes a handful or &quot;strick&quot; of rough flax, winds the top end around his hands, and then, spreading out the root end as broad and flat as possible, by a swinging motion dashes the fibre into the teeth or needles of the rougher or &quot; ruder&quot; heckle. The rougher is a board plated with tin, and studded with spikes or teeth of steel about 7 inches in length, which taper to a fine sharp point. The heckler draws his strick several times through this tool, working gradually up from the roots to near his hand, till in his judgment the fibres at the root end are sufficiently combed out and smoothed. He then seizes the root end and j similarly treats the top end of the strick. The stricks, as finished, are carefully piled up in a regular manner, keep ing each handful separate for convenience of future treat ment. The same process is again repeated n a similar tool, the teeth of which are 5 inches long, and much more closely studded together; and for the finer counts of yarn a third and a fourth heckle may be used, of still increasing fineness and closeness of teeth. In dealing with certain varieties of the fibre, for fine spinning especially, the flax is, after roughing, broken or cut into three lengths the top, middle, and root ends. Of these the middle cut is most valuable, being uniform in length, strength, and quality. The roat end is more woody and harsh, while the top, though fine in quality, is uneven and variable in strength. From some flax of extra length it is possible to take two short middle cuts ; and, again, the fibre is occasionally only broken into two cuts according to the judgment and requirement of the manufacturer. Flax so prepared is known as &quot; cut line &quot; in contradistinction to &quot; long line &quot; flax, which is the fibre unbroken. The sub sequent treatment of line, whether long or cut, does not present sufficient variation to require further reference to these distinctions. In the case of heckling by machinery, the flax is first roughed and arranged in stricks, as above described under hand heckling. Considerable variations are presented in the construction of heckling machines, but the general principles of those now most commonly adopted, such as the machines of Combe, of Homer, or of Cotton, &c., are identical. These are known as vertical sheet heckling machines (fig. 1), their essential features being a set of end less leather bands or sheets f, g revolving over a pair of rollers c, h in a vertical direction. These sheets are crossed by iron bars, to which heckle stocks, furnished with teeth, are screwed. The heckle stocks on each separate sheet are of one size and gauge, but each successive sheet in the length of the machine is furnished with stocks of increasing fineness, so that the heckling tool at the end where the flax is entered is the coarsest, while that to which the fibre is last submitted has the smallest and most closely set teeth. Thus the whole of the endless vertical revolving sheet presents a continuous series of heckle teeth, and the machines are furnished with a double set of such sheets revolving face to face, so close together that the pins of | one set of sheets intersect those on the opposite stocks. ! Overhead, and exactly centred between these revolving ! sheets, is the head or holder channel a, from which the flax hangs down while it is undergoing the heckling process on : both sides. The flax is fastened in a holder 1&amp;gt;, consisting of | two heavy flat plates of iron, between which it is spread and tightly screwed up. The holder is 11 inches in length, and the holder channel is fitted to contain a line of six, eight, or twelve such holders, according to the number of separate bands of heckling stocks in the machine. The head or holder channel has a falling and rising motion, by which it first presents the ends and gradually more and more of the length of the fibre to the heckle teeth, and, after dipping down the full length of the fibre exposed, it slowly rises and lifts the flax clear of the heckle stocks. By a reciprocal motion the whole of the holders are then moved forward one length ; that at the last and finest set of stocks is thrown out, and place is made for filling in an additional holder at the beginning of the series. Thus with a six-tool heckle, or set of stocks, each holder full of flax from beginning to end descends FIG. 1. Section of Combe s Heckling Machine. into and rises from the heckle teeth six times in travelling from end to end of the machine. The root ends being thus first heckled, the holders are shot back along an inclined plane, the iron plates undamped, the flax reversed, and the top ends are then submitted to the same heckling operation. The tow made in the heckling process is cleared from the heckle teeth, as they revolve, by doffers I, I, which in travelling upwards are, by passing over special guide rollers e, e, projected out from the line of the heckle teeth. The doffers themselves are cleared by fixed combs cf, d, and the tow falling down is collected in troughs I; k on each side of the machine. Tow, which is a much less valuable substance than dressed line, undergoes a some what different preparing process, and is used only for the lower numbers of yarn. Preparing. The various operations in this stage have for their object the proper assortment of dressed line into qualities fit for spinning the different counts or sizes of yarn for which it may be suitable, and the drawing out of the fibres to a perfectly level and uniform continuous ribbon or sliver, containing throughout an equal quantity of fibre in any given length. From the heckling the now smooth, glossy, and clean stricks are taken to the sorting room, where they are assorted into different qualities by the &quot; line sorter,&quot; who judges by both eye and touch the quality and capabilities of the fibre. So sorted, the material is passed to the spreading and drawing frames, a series or system of machines all similar in construction and effect. The essential features of the spreading frame are (1) the feeding cloth or creeping sheet, which delivers the flax to (2) a pair of &quot; feed and jockey &quot; rollers, which pass it on (3) to the gill frame or fallers. The gill frame con- XIV. 84