Chapter C: D E F are the four printing cylinders, named in the order of their (27)

After the strick of flax has been thus carried through the scutching machine or the heckling machine, the jaws of the clamps are to be opened, the ends of the flax reversed, and the strick again confined in the clamps, so that the other end of the strick may be operated upon in a similar way. In order to prevent any part of the flax from attaching itself to the branches of the movable frames, each frame is furnished with a shield or guard of polished iron or brass plate, which covers a part of the combs and the heads of the screws by which they are fixed to the branches. When the plate metal is bent into the form of a shield, it is slipped on to the branches of the heckle frames, and is sufficiently elastic to hold fast.

But it is to be observed, that the edges of the shields are to vary in the extent of their projection according to the situation in which they are to be placed; those which are to shield the upper branches of heckles are to project but little, so as to leave the points uncovered and free to enter the strick of flax; but the shields of the lower heckles are to project considerably over the points, to prevent them from penetrating too far into the fibres, which is so contrived for the purpose of facilitating the falling of the tow, which would otherwise be with difficulty removed from the lower combs, were it thrust upon the whole length of the points.

It being advantageous that each strick of flax should be combed near the lower extremities before the middle is acted upon, it is necessary, in order to obtain this effect, to remove some of the points of the combs in the upper branches. By these means, the operation of the heckles upon the flax begins and proceeds gradually, and ceases at the opposite extremity of the machine in the same gradual way, which is very advantageous in clearing completely the flax from the tow.

IV. _Flax spinning._--If we compare flax with other spinning materials, such as wool and cotton, we shall find it to possess several characteristic properties. While cotton and wool are presented by nature in the form of insulated fibres, the former requiring merely to be separated from its seeds, and the latter to be purified from dirt and grease before being delivered to the spinner, flax must have its filaments separated from each other by tedious and painful treatment. In reference to the spinning and the subsequent operations, the following properties of flax are influential and important:--

1. The considerable length of the fibres, which renders it difficult, on the one hand, to form a fine, level, regular thread, on the other, gives the yarn a considerably greater tenacity, so that it cannot be broken by pulling out the threads from each other, but by tearing them across.

2. The smooth and slim structure of the filaments, which gives to linen its peculiar polished aspect, and feel so different from cotton, and especially from woollen stuffs, unless when disguised by dressing. The fibres of flax have no mutual entanglement, whereby one can draw out another as with wool, and they must therefore be made adhesive by moisture. This wetting of the fibres renders them more pliant and easier to twist together.

3. The small degree of elasticity, by which the simple fibres can be stretched only one twenty-fifth of their natural length before they break, while sheep’s wool will stretch from one-fourth to one half before it gives way.

Good flax should have a bright silver gray or yellowish colour (inclining neither to green nor black); it should be long, fine, soft, and glistening, somewhat like silk, and contain no broad tape-like portions, from undissevered filaments. Tow differs from flax in having shorter fibres, of very unequal length, and more or less entangled. Hemp agrees in its properties essentially with flax, and must be similarly treated in the spinning processes.

The manufacture of linen and hemp yarn, and the tow of either, may be effected by different processes; by the distaff, the hand-wheel, and spinning machinery. It will be unnecessary to occupy the pages of this volume with a description of the first two well known domestic employments. I shall therefore proceed directly to describe the last method, or

_Spinning of Flax by Machinery._--This branch of manufacture has been much more recently brought to a practical state than the spinning of cotton and wool by machines, of which the cause must be sought for in the nature of flax as above described. The first attempts at the machine spinning of flax, went upon the principle of cutting the filaments into short fragments before beginning the operation. But in this way the most valuable property of linen yarn, its cohesive force, was greatly impaired; or these attempts were restricted to the spinning of tow, which on account of its short and somewhat tortuous fibres, could be treated like cotton, especially after it had been further torn by the carding engine. The first tolerably good results with machinery seem to have been obtained by the brothers Girard at Paris, about the year 1810. But the French have never carried the apparatus to any great practical perfection. The towns of Leeds in Yorkshire, of Dundee in Scotland, and Belfast in Ireland, have the merit of bringing the spinning of flax by machines into a state of perfection little short of that for which the cotton trade has been so long celebrated.

For machine spinning, the flax is sometimes heckled by hand, and sometimes by machinery. The series of operations is the following:--

1. The heckling.

2. The conversion of the flax into a band of parallel rectilinear filaments, which forms the foundation of the future yarn.

3. The formation of a sliver from the riband, by drawing it out into a narrower range of filaments.

4. The coarse spinning, by twisting the sliver into a coarse and loose thread.

5. The fine spinning, by the simultaneous extension and twisting of that coarse thread.

The spinning of tow requires a different treatment: we shall first treat of the heckling of flax by machines; and secondly, of the mechanical spinning of flax. The mechanical carding and spinning of tow are very similar to those of cotton; which see. Though machine heckling be far from perfect, yet the tow it throws off can be spun into very good yarn by machines, while it would afford very indifferent yarn to the hand spinner.

All heckle machines have this common property, that the flax is not drawn through them, as in working by hand, but on the contrary, the system of heckles is moved through the flax properly suspended or laid. Differences exist in the shape, arrangement, and movements of the heckles, as also in regard to the means by which the adhering tow is removed from them. The simplest and most common construction is to place the heckles upon the surface of a horizontal cylinder, while the flax is held either by mechanical means or by the hand during its exposure to the heckle points. Many machines have been made upon this principle. It is proper in this case to set the heckle teeth obliquely in the direction in which the cylinder turns, whereby they penetrate the fibres in a more parallel line, effect their separation more easily, and cause less waste in torn filaments. To conduct the flax upon the cylinders, two horizontal fluted rollers of iron are employed, which can be so modified in a moment by a lever as to present the flax more or less to the heckling mechanism. The operator seizes a tress lock of flax with her hand and introduces it between the fluted rollers, so that the tips on which the operation must begin, reach the heckles first, and by degrees the advancing flax gets heckled through two-thirds or three-fourths of its length, after which the tress or strick is turned, and its other end is subjected to the same process. By its somewhat rapid revolution the heckle cylinder creates a current of air which not only carries away the boomy particles, but also spreads out the flax like a sheaf of corn upon the spikes, effecting the same object as is done by the dexterous swing of the hand. The tow collects betwixt the teeth of the heckle, and may, when its quantity has become considerable, be removed in the form of a flock of parallel layers.

The essential parts of such a construction will be understood from _fig._ 438., though the fluted rollers are absent. The flax _a_, _b_, is held by the hand, or in a kind of clamp. The cylinder is partly covered with a curvilinear plate of iron _c_, _d_, which serves to sustain the flax, and to guide it in circular tresses round the periphery of the heckle. At the beginning it is placed near _b_, when the tips of the flax are only presented to the heckles; during the working the shield is continually drawn back in the direction from _d_ to _c_, and thus lets the operation be performed upon the remaining part of the flax.

_First operation; the conversion of flax into ribands or slivers._--This is effected by subjecting the flax to a series of advancing gills or heckle-teeth, and at the same time drawing out its fibres by means of rollers. _Figs._ 439, 440, 441, show the outline of the construction of a machine for this purpose. Here two rows of heckles are placed alongside of each other, though only one of them be shown in the ground plan, _fig._ 440., in order to allow the parts beneath the other to be seen. The flax is placed in the sheet iron channels _a a_, by laying down one handful after another, so that the points of the second strick reach to only the middle of the first, and thus preserve a uniformity of thickness in the feeding. This process is necessary, since, as every one knows, the heckled stricks are always thick in the middle, and thin at the ends. The flax being introduced between the rollers _b_ and _c_, is drawn out by their agency, and at the same time subdivided by the heckles _d_, between whose teeth the pins of the roller _e_ press it down. At the rollers _f_³ it is loosened from the heckles by the transverse bars which rise from the springs _g_, after which it is seized by the rollers _h i_, and drawn again. A little beyond these rollers, it runs through a funnel _l_, in order to gather the fibres together; in front of these rollers the slivers from both rows of heckles are united, and proceed in one riband through that polished brass funnel; the rollers _m n_ extend this riband, pressing it gently together, and then let it fall into a tin can. The union of the two slivers contributes to the uniformity, since the irregular thicknesses are thereby compensated. The diameter of the roller _c_, is equal to that of each of the cylinders _f_, _f_¹, _f_², _f_³; and the whole five move with equal velocity. The same correspondence exists between the rollers _n_ and _i_. Thus the sliver of flax is not stretched either by its passage from _e_, upon the heckles, nor between _i_ and _n_, but solely in passing from the heckles to the rollers _i h_. The heckle teeth of this machine do not stand perpendicularly, but are bent somewhat backwards; so as to retain the flax more firmly. The revolving cylindrical brush _o_, is placed over and a little in front of the pressing roller _h_, in order to take off all the filaments of flax adhering to their circumference, and to toss them onwards where they may again unite with the slivers. For the sake of perspicuity, the rollers _h_, and those brushes are left out in _fig._ 440., but the latter are particularly shown in _fig._ 442., while a portion of their axis _q_, is however shown in _fig._ 440. The pressure of the cylinder _h_, upon the cylinder _i_, is produced by the weight _r_, _fig._ 439., which hangs upon the lever _s_; the lever pulls down at _t_, a vertical rod, whose upper hook-shaped end embraces the axis of _h_ in the middle of its length.

_Second principal operation; the formation of rovings._--Mr. Wordsworth’s improvements in machinery for preparing, drawing, and roving flax, hemp, wool, and other fibrous substances, consists in a novel contrivance or mechanism to be adapted to the machine commonly called the gill, employed for preparing, drawing, and roving flax and hemp, and for combing and spinning long wool; which improvements allow the points of the travelling heckles to continue longer in operation than in the ordinary construction of gill, and cause the heckle points to be withdrawn from the fibres at the end of the stroke without the possibility of their drawing the fibres down with them.

The manner of effecting this object will be seen by reference to the several figures which exhibit a gill on this improved plan in different views. _Fig._ 443. is a plan or horizontal view, exhibiting the upper surface of the machine; and _fig._ 444. is a longitudinal section taken through the middle of the machine: _fig._ 445. is a representation of the front of the machine, but in which several parts have been removed to show the action of the heckles more perfectly.

The several heckles _a a a_ are formed by a series of needles or heckle points set into a metal bar, as represented on an enlarged scale in _figs._ 446. and 447. These bars are each of them suspended in a frame or carriage _b b b_ (shown in two views at _figs._ 448. and 449.), by means of double jointed levers _c c_, seen in two positions, at _figs._ 450. and 451.; the heckle bar, its levers and carriage or frame, being shown put together in _figs._ 452. and 453.

When the heckles are in operation, the points are raised, as in _fig._ 452.; but when they are withdrawn from the fibres, then the points are sunk down into the carrying frames, as _fig._ 453.

These two positions of the heckles are produced by the knobs or parts _d_, that project from the jointed levers _c_, acting against the edges of guide bars, which will be explained in describing the operations of the machine.

The several heckles are adapted and made to work in the machine by attaching the ends of the respective frames or carriages _b_, to travelling endless chains _e e_, seen in _figs._ 443., 444., and 445. These endless chains pass over fluted guide rollers _f f_, seen best in _figs._ 444. and 445., and over horizontal bars _g g_, seen best in _figs._ 443. and 444. The chains with the heckles are driven through the machine by rotatory spur wheels _h h_; see _figs._ 443. and 444., the teeth of which take into the spaces between the cylindrical parts of the several heckle carriages _b b_, and consequently drive the heckles forward; and these spur wheels are actuated by a train of toothed geer from the first driving shaft _i_, which gives motion to all the operative parts of the machine.

If flax, hemp, long wool, or other fibrous material, be passed into the machine at the back part by a feeding cloth or creeper through a guide _k_, best seen in _figs._ 443. and 444., and be conducted under and over the feeding rollers _l_, _m_, and _n_, and over the heckles _a a a_ to the drawing rollers _o_ and _p_, and thence to the flyer and bobbin, or to a receiving can, the fibres will be opened in their progress, and combed by the points of the heckles entering into and separating the fibres, the material being drawn by a different speed to that with which the heckles travel.

This operation of preparing, drawing, and roving flax and hemp, and the general construction of a machine of this kind being well understood, it is not necessary to explain its details, excepting as respects those parts which constitute the present improvements.

It will be perceived, by reference to _figs._ 443. and 444., that the knobs _d_, which project from the jointed levers _c_, as they travel along the machine, bear against the outer edges of the two fixed guide bars _q q_ that extend along the top of the machine above the heckles, which keep the heckle points raised, as in _fig._ 451. This will also be very evidently seen in the front view of the machine, _fig._ 445., where the upper heckle bar _a_ is raised in its carriage _b_, by the knobs _d d_ bearing against the outer edges of these guide bars _q q_. But when the endless chains _e e_, which support and conduct the frames or carriages of the heckles, have advanced the heckle points to within a very little distance of the drawing rollers (see _fig._ 444.) then the knob _d_ of the jointed levers at each end of the heckle bar passes the ends of the guide bars _q q_, and they immediately come in contact with two inclined planes _r r_, seen in _figs._ 443. and 444., which instantly depress the levers _c_, and consequently cause the heckle bar _a_, with its points to descend in the frame or carriage _b_, withdrawing the points from the fibres of the material almost in a perpendicular direction.

The heckles that have become thus depressed pass with their carriages by the traversing of the endless chains along the under part of the machine, and when they arrive at the back, and begin to rise, the guide bars _q q_, being at their commencement slightly bent, conduct the knobs _b_ of the levers _c_ until they are forced back into the positions first described, whereby the heckle points are raised, as they come to the upper part of the machine, into effective operation. The fibres of material operated upon, after passing through the drawing process between the rollers, may be roved, twisted, or spun, by the employment of a bobbin and flyer, as shown in _fig._ 444., or may be delivered into a can, to be roved, twisted, or spun, by other machinery, by substituting a pair of conducting rollers instead of the bobbin and flyer, which shall conduct the sliver of material into a tin can below.

The descent of the heckles _a_, into their frames _b_, by the falling of the levers _c_, _c_, precludes the possibility of the fibres of the material operated upon being carried down under the machine by the points, as frequently happens in gill machines of the ordinary construction; and this mode of mounting the heckles and traversing them with the assistance of the guide bars _q_, _q_, and inclined planes _r_, _r_, allows the heckle points to be brought much nearer to the drawing rollers _o_, _p_, by means of the metal bars in which the heckle points or needles are set, falling below the centre of the endless chain _e_, _e_, as shown in _figs._ 443. and 444., and thereby affords the means of preparing, drawing, and roving various qualities of flax, hemp, wool and other fibrous materials, particularly such as have a much shorter staple than any fibrous materials hitherto operated upon in gill machinery.

Another most ingenious and effective improvement made of late years in the flax spinning machinery, is that patented by Messrs. Westley and Lawson, in August 1833, and since then introduced into practice with great advantage. It applies to the _gill_ or mechanism employed for opening, straightening, and separating the fibres of flax, hemp, and long wool in the operation of slivering. The peculiar feature here is a method of driving the heckle bars through the gill machine by means of perpetual screws or worm shafts, instead of by chains and spur wheels, as in the former constructions.

The heckle bars which lie across the machine, are, by the present patentees, supported at their ends by fixed horizontal guide rails, on which they slide, while the extremities of the heckle bars are inserted in the helical grooves of the worm shafts, which are placed in horizontal positions at the sides of the machine; and hence the rotatory motions given to these screw shafts, cause the heckle bars to be driven along the guide rails with an uniform simultaneous movement.

The heckle bars having performed their usual office, that is, having combed and separated the fibres of the material as they move onward, are at the front part of the machine depressed and put out of operation by means of rotatory cams; and by the assistance of guide levers, each heckle bar, when it arrives at the end of the upper horizontal guide rail, is conducted down to the lower horizontal guide rails, where the extremities of the comb-bars falling into the helical grooves of a lower pair of worm shafts, revolving in an opposite direction to the former, thereby give the heckle bars a retrograde movement. When they arrive at the back end of their horizontal guide rails, they are, by similar rotatory cams, raised again to the upper horizontal guide rails, which coming into geer with the upper worm shafts, are moved onwards as at first.

By this means a succession of heckles is continually advancing upon the upper guide rails, having their points in constant operation between the fibres of the textile materials, while their vertical position is secured during their whole course.

_Fig._ 454. is a horizontal representation of a gill machine, shewing the present improvements; but some of the upper portions of the machine are removed, to let the working parts be seen more clearly. _Fig._ 455. is a side view of the gill; and _fig._ 456. a vertical section taken longitudinally. The driving rigger or pulley _a_, is fixed upon the front roller _b_, commonly called the drawing roller, because when pressed upon by the upper wooden roller _c_, it draws out the fibres between them. The rollers _d_, _e_, _f_, are the ordinary back or holding rollers, for retaining the fibres, while they suffer powerful traction by the rollers _b_, _c_, over the needles or points of the heckle bars. The upper guide rail above mentioned, upon which the heckle bars slide, is shown at _g_, in _fig._ 456., and the lower guide rail at _h_; the series of heckle bars with their needles are represented at _i_, _i_, _i_, _i_, _i_, _i_; the upper worm shafts _k_, _k_, are mounted in brackets made fast to the sides of the frame; a similar pair of worm shafts _l_, being mounted in like manner below. These worm shafts _k_ and _l_, on each side are connected together by toothed wheels _m_, and upon the axles of the lower worm shafts, bevelled pinions _n_ are fixed, which take into corresponding bevel pinions on the transverse shaft or axle _o_. This shaft _o_, being connected by a train of toothed wheel work with the axle of the drawing roller _b_, as shown in _figs._ 454. and 455., the rotation of the roller _b_, causes the shaft _o_ to turn also, and the bevel geer _n_ and _o_, produce the rotatory motion of the worm shafts _k_ and _l_, which turn in contrary directions.

It will be seen, from _fig._ 454., that the ends of the heckle bars _i_, have nibs or projections which fall into the grooves of the screw or worm shaft, and that being supported below, upon their guide rails, as the worm-shafts _k k_ revolve, the upper range of heckle bars will be progressively advanced towards the front part of the machine. By referring to _fig._ 456. it will be perceived, that as each heckle bar arrives at the front end of the guide rail _g_, a finger _p_, called a tappet or cam, on the shaft _k_, strikes it down to the lower guide rails _h_; and, in order that its descent may be truly vertical, weighted levers _q q_, in front, are made to press against the face of the heckle bar as it descends. This bar having now arrived at the lower guide rails _h_, lets fall its nibs into the grooves of the lower worm shafts _l_, by whose rotation the heckle bar is made to retrograde, or return towards the back of the machine. When the heckle bar has reached the hinder end of the guide rail _h_, a finger or tappet, _r_, on the lower worm shaft, comes under it and raises the heckle bar, guided by the back-weighted levers _s_, as shown in _fig._ 456., till it is elevated to the level of the upper guide rail _g_; when the threads of the upper worm-shafts take hold of its nibs as before, and conduct it forward upon the guide rail in the way already described. Thus the continued rotation of the worm shafts _k k_, and _l l_, causes the whole series of heckle bars to travel along the guide rails, and the tappets _p_ and _r_, by alternately depressing and raising them at the ends of the said rails, cause them to move in a regular circuit, yet so as to preserve their verticality.

The claim made under this patent is, for every mode in which screw or worm shafts may be adapted to conduct the bars carrying the needles or heckle-teeth through a machine for preparing, drawing, or roving textile fibres.

In December 1835, Messrs. Hope and Dewhurst obtained a patent for improvements in the manufacture of flax, which deserve notice. These are of both a chemical and mechanical nature. The first consists in steeping the flax in dilute sulphuric acid, of a certain strength, and for a certain time, proportioned to the quality of the fibres, the coarser requiring the stronger application. By this means the gummy matter and the outer shell will be loosened and easily detached. It is then to be passed between squeezing rollers, afterwards well washed, boiled in a solution of soap and water for a few hours, and finally passed again through the rollers. These processes may be repeated till the flax acquires the desired glossiness and separation of fibres. It is next to be beaten, and passed once or twice over an ordinary heckle or stiff brush.

The second part, or the mechanical, is represented by the figures 457., 458., 459., 460., and 461. _Fig._ 457. is a sectional elevation in part of the construction of the spindle, bobbin and flyer proposed for spinning all kinds of flax or hemp. _Fig._ 458. answers for spinning coarser yarns; _fig._ 459. shows how yarns are to be spun for weft, and wound upon what is called a “pin cop bobbin.”

_a a a_ is the stationary or fixed spindle of the ordinary throstle frame, which is surrounded by the tube _b b_, and connected to the wharve or pulley _c_, by which the flyer _d_ is driven. The flyer is furnished with guides or conductors _e e_, which lead the yarn immediately to the bobbin; this flyer is also provided with a small central shaft which supports it, and runs in the small cup or recess at the top of the stationary spindle _a_, and is fixed with the flyer to the tube _b b_, which is altogether carried round or driven by the wharve _c_.

It will be seen by _fig._ 460., that the wharve _c_, and tube _b_, are connected at bottom by a half-lap coupling joint or clutch; this is for the purpose of allowing the tube _b_ to be slidden up the spindle, and more readily removing the bobbin when it is full of yarn, without stopping the frame, or removing the band from the wharve _c_, the tube of which runs in the step or cup _h_, fixed upon the bolster rail near the bottom of the throstle frame. The traversing of the bobbin or the copping motion is effected exactly in the same manner as in ordinary throstles, that is, by the lifting and lowering of the copping rail _i_, which in this instance supports the bobbin. In _fig._ 458. the flyer is constructed of twice the length of the bobbin, to allow this to rise and fall freely within it, and is connected at top by a slight cross piece, for the purpose of preventing the arms of the flyer from expanding by the centrifugal force, when turning with great velocity. The flyer for spinning coarse numbers requires to have an inner tube _k_, to support the spindle. The bobbins are supported upon a washer _l_, _l_. The spindle is allowed to revolve in a slight degree by the friction of the drag-weight _m_, _m_. This weight has a hole formed in it with a flat side, as shown in _fig._ 461.

Flax has been for a long period spun wet in the mills; a method no doubt copied from the practice of housewives moistening their yarn with their saliva at the domestic wheel. Within a few years the important improvement has been introduced, of substituting hot for cold water, in the troughs through which the fibres in the act of spinning pass. By this means a much finer, smoother, and more uniform thread can be spun than in the old way. The flax formerly spun to twelve pounds a bundle, is, with hot water, spun to six. The inconvenience of the spray thrown from the yarn on the flyers remains; aggravated by increased heat and dampness of the room, where this hot process goes on. Being a new expedient, it receives daily changes and ameliorations. When first employed, the troughs of hot water were quite open; they are now usually covered in, so as almost entirely to obviate the objections to which they were previously liable. With the covers has been also introduced a new method of piecening or joining on any end, which may have been run down, namely, by splicing it to the adjoining roving, whereby it is carried through the water without imposing a necessity on the spinner to put her hand into the water at all. In some places she uses a wire, for the purpose of drawing through the end of the roving to mend a broken yarn.

This may be considered the inherent evil of flax-spinning,--the spray thrown off by the wet yarn, as it whirls about with the flyer of the spindles. A working dress, indeed, is generally worn by the spinners; but, unless it be made of stuff impermeable to water, like Macintosh’s cloth, it will soon become uncomfortable, and cause injury to health by keeping the body continually in a hot bath. In some mills, water-proof cloth and leather aprons have actually been introduced, which are the only practicable remedy; for the free space which must be left round the spindles for the spinner to see them play, is incompatible with any kind of fixed guard or _parapluie_.

There was before the late Factory Bill passed, a class of very young children employed in the flax mills, under the name of little doffers, forming generally a troop of from four to ten in each spinning-room, who, the moment they perceived the bobbins of any frame or side of a frame exhausted of roving, ran together, and furnished it with full ones as quickly as possible. They were not numerous in all, but they had an occupation requiring a great activity and attention. It was practised also in the fine spinning-rooms, which are perfectly free from dust; and, as it involved a kneeling and stooping position, seemed peculiarly appropriate to children, and is still done by them at a somewhat more advanced age.

The adjoining _fig._ 462. will serve to explain the mechanism by which the fine spinning of flax is performed. The front pair of drawing rollers represented at F, was at one time moistened by letting water trickle upon it, from a vessel B, furnished with a stopcock placed a little above, or by immersing one half of the under-roller in the water-trough as at A. The roller pair C, which receives the fine rovings from bobbins placed on skewers or upright pins in the creel behind, is so mounted as to be fixed at any desired distance from the front rollers F. This distance should be always a little more than the average length of the filaments of the line; for if it were equal to it, they would be seized at both ends by the two pairs of rollers, which move with different velocities, and would be torn asunder, instead of being drawn out alongside of each other. The front rollers indeed move in many such machines four times faster than the back pair. The rest of this flax-spinning apparatus resembles in every respect the throstle frame of the cotton-spinner. The thread, as it escapes from the front rollers, gets twisted by the spindle and flyer, and wound up in constant progression on the bobbin, the motion of the latter being retarded either by a washer of leather beneath its lower end, or sometimes, as shown in the figure, by a weighted lever H, suspended from a cord, which embraces the pulley-groove turned on the lower end of the bobbin. This friction of this cord on the pulley, which may be varied by changing the length of leverage at which the weight acts, gives the bobbin the requisite retardation for winding up the yarn.

The bobbin G, at the same time that it has this retarded movement of revolution on its axis, has another motion up and down on the spindle I, to present itself at different points to the thread, and to cause the equal distribution of this over the surface of the bobbin-barrel. This latter motion is given by a double eccentric L, which by turning slowly on its axis, makes the balance-lever M oscillate, and thereby raises or depresses the bobbin-rail with its row of spindles. N is a section of the long tin drum, which extends the whole breadth of the frame, and communicates its rotatory motion, derived from the steam-pulley, to the spindles, by the intervention of the endless cotton cords O, as also to the fluted rollers C, F, and to the axis of the heart-shaped or eccentric wheel L, working in an endless screw.

The ratio of the velocity of the rollers of supply C, with the front or delivering rollers F, and with the spindles, is proportional to the fineness of the yarn. For low numbers, the draught is usually fourfold. The speed of the spindles also varies with the quality of the yarn, according as it is intended for warp or weft; the former requiring more twist than the latter; but never so much as to cause it to snarl into a knot, when left free to turn on itself.

One of the most important improvements hitherto made in the spinning of flax is that for which James Kay, of Preston, obtained a patent in July, 1825. Its peculiar feature is the maceration in warm water of the slivers or rovings, previously to spinning them, by conducting them into tin cans, with open bottoms, fitted into circular boxes having holes like a cullender, and immersed into a trough of warm water. The slivers as they pass from the rollers are let fall through the cans into these boxes, when they are to be repeatedly pressed and beaten down by a plunger, or the action of rollers, as may be most convenient. The material must be thoroughly freed from air, and macerated. After five or six hours it is to be removed from the water, and placed in its compressed state at the back part of a drawing and spinning machine. The cake being now turned over, the end of the roving first deposited in the can is drawn out with care, then raised up, and passed over a tension roller to the drawing apparatus. The first pair of rollers for the drawing process merely retains the filaments; while at a distance of two inches and a half the drawing rollers are placed. Both are fluted for the purpose of taking firm hold of the material; and the drawing pair is made to move eight times quicker than the retaining. As the flax fibres have in this state little or no elasticity, and as they adhere loosely in their macerated condition, the drawing rollers must be placed thus close to the retaining rollers, and being made to move at a proper speed, produce an extremely attenuated thread.

The adjoining table represents, in three compartments, the most important rooms in a flax-mill, viz.:--

I. The tow preparing room.

II. The line preparing room for the long flax.

III. One room of spinning machines as a pattern for the rest.

A, lap machine; B, 4-feet breaker card; C, 3 feet 6 inches ditto; D, 3-feet finisher card, 3 workers; E, cut tow, second drawing, 5 heads; F, cut tow, first drawing, 4 heads; G, cut tow, reg. roving, 32 spindles; H, 4-feet breaker card; I, 4-feet finisher ditto; K, long tow, first drawing, 3 heads; L, long tow, second drawing, 4 heads; M, long tow, roving 4 spindles.

A, cut line, first drawing; B, cut line, second drawing, 4 heads; C, cut line, third drawing, 5 heads; D, cut line, reg. roving 32 spindles each; E, long line, first drawing; F, long line, second drawing, 3 heads each; G, long line, third drawing, 4 heads each; H, long line, roving 16 spindles.

I. The line preparing room comprehends:--
1. Heckling machines with heckles.
2. Line spreaders, or first drawing slivers.
3. Frames for the second drawing, of 3 heads each.
4. Frames for the third drawing, of 4 heads each.
5. Roving frames of 16 spindles each.
6. Spare fallers for first drawing with gills.
7. Ditto ditto for second and third drawing with ditto.
8. Ditto ditto for roving.

II. The cut flax line preparing room:--
1. Sets of heckling frames (excentric.)
2. Cutting or breaking machine.
3. Line spreaders or drawing ditto.
4. Frames for second drawing, 4 heads each.
5. Ditto third ditto, 5 ditto.
6. Ditto, regulator roving, 32 spindles each.
7. Spare fallers with gills for first drawing.
8. Ditto, ditto for second and third ditto.
9. Ditto, ditto, with gills for roving.

III. Long or uncut flax tow preparation:--
1. Lap machine.
2. Breaker cards, 4 feet diameter.
3. Finisher ditto, ditto.
4. Frames for first drawing, 3 heads each.
5. Ditto for second drawing, 3 heads each.
6. Ditto for roving, 16 spindles each.
7. Spare fallers, with gills for first and second drawing.
8. Ditto, ditto, ditto, for roving.

IV. Cut flax tow preparation:--
1. Lap machine.
2. First breaker cards, 4 feet diameter.
3. Second ditto, ditto, 3 feet 6 inches ditto.
4. Finisher cards with 8 workers.
5. First drawing frames, of 4 heads each.
6. Second ditto, ditto, of 5 ditto.
7. Frames for regulator roving, 32 spindles each frame.
8. Spare fallers with gills for first and second drawing.
9. Ditto, ditto, for roving.

V. Spinning rooms for both lines and tows:--spindles in frames in a
number proportional to the number of the above preparation
machines; and consequently to the quantity and quality of the
flax yarn intended to be spun.

VI. Utensils and tools; such as cards clothing with needle pointed
filleting.

Observations upon the above statement of the series of machinery requisite in a modern flax mill of the most improved construction:--

The long or uncut flax to be spun into yarns averaging 30 leas per lb.

Each heckling machine will produce about 4-1/2 cwts. per day, which would be distributed into 200 lbs. of line, and 266-2/3 of tow.

The total with 3 machines would be therefore 600 lbs. of line, and 800 lbs. of tow.

The preceding statement contains three systems of line preparing, each system being composed of--

1 line spreader, or first drawing;
1st frame of 3 heads; 2d ditto, 2 slivers each;
1 ditto of 4 ditto; 3d ditto, ditto ditto;
2 ditto rovings of 32 spindles, which are capable of supplying about
640 spinning ditto;
1 line spreader being allowed for contingencies.

The above statement contains 3 systems of tow (uncut) preparation, each system being composed of--

1 breaker card;
2 finisher ditto,
1 frame of first drawing, 3 heads of 4 slivers each;
1 ditto second ditto, 4 ditto, 4 ditto ditto;
2-1/3 ditto rovings or 37 spindles, which are capable of supplying
about 660 spinning ditto;
1 lap machine being sufficient for 2 or 3 systems;
1 extra finisher is deemed desirable.

The statement contains 2 systems of heckling machines for cut flax, a system consisting of either 8 or 10 machines; for the coarser work, 8 machines in succession finer and finer, are sufficient; but for the finest 10 or 12 are required. Each system will produce between 2 and 300 lbs. per diem, of raw flax, heckled, divided on the average into 170 lbs. line, 280 lbs. tow, which will about equal the supply of the 5th system contained in the statement, each consisting of--

1 line spreader or 1st drawing;
1 frame 2d drawing; 4 heads 4 slivers each;
1 ditto 3d ditto, 5 ditto 4 ditto ditto;
1 ditto roving 32 spindles;
and are capable of supplying about 480 ditto, of spinning.

The statement contains 2 systems of tow (cut flax) preparings, each system being composed of--

2 second breaker card;
4 finishers ditto;
4 frames 1st drawing, 4 heads each 4 slivers;
4 ditto 2d ditto, 5 ditto ditto, 4 ditto;
4 regulator rovings 128 spindles,
and are capable to supply about 1800 spinning ditto.
1 first-breaker card and lap frame are sufficient to 2 or 3 systems.

Summary view:--

Long or uncut line 3 systems of 640 spindles = 1920
Ditto -- tow 3 ditto 660 ditto 1980 3900
----
Cut -- line 5 ditto 480 ditto 2400
Ditto -- tow 2 ditto 1800 ditto 3600 6000
---- ----
Total of spinning spindles 9900

3900 spindles, at an average of 30 leas yarn per lb., would turn off 9 leas per spindle per diem with waste circa 1400 lbs.

6000 spindles, at an average of 100 leas yarn per lb., would turn off 6 leas per spindle per diem with waste circa 450 lbs.

Yarns produced: _£. s. d._
Of average 30 leas per lb. per week circa 1050 boles at
9_s._ 472 10 0
Of ditto 100 ditto -- -- 1080 -- 486 0 0
---- ----------
Total weekly produce 2130 958 10 0

_£. s. d._
Weekly charges, wages, &c. 150 0 0
Flax 400 0 0
Weekly expenses 40 0 0
Interest on 60,000_l._ } 120 0 0
10 per annum } 710 0 0
--------- ----------
Weekly profit 248 10 0

Measures of flax yarn; and statistics of the linen trade for the United Kingdom.

One lea of flax yarn at Leeds is = 300 yards.
One spindle Scotch = 38 leas = 11400 yards.
One rand = 6 ditto = 1800 ditto.
One dozen is 12 rands = 72 ditto = 21600 ditto.

When yarn is estimated in Nos. it implies the number of leas in one pound weight; as in cotton, it means the number of hanks of 840 yards each in one pound.

_Imports of flax and tow, or codilla of hemp and flax, at a duty of 1d. per cwt., in_

1834. 1835. 1837. 1838.
------- ------- --------- ---------
lbs. lbs. lbs. lbs.
811,722 740,814 1,529,116 1,002,256

_Retained for
consumption._ 794,272 728,143 1,532,059 1,002,408

Linen yarn exported 2,611,215

Linen manufactures exported,
including flax yarn, declared
value _£_3,208,139 _£_3,645,097 _£_2,613,293

FLINT. (_Pierre à fusil_, Fr; _Feuerstein_, Germ.) The fracture of this fossil is perfectly conchoidal, sometimes glossy, and sometimes dull on the surface. It is very hard, but breaks easily, and affords very sharp-edged splintery fragments; whence it is a stone which strikes most copious sparks with steel. It is feebly translucid, has so fine and homogeneous a texture as to bear polishing, but possesses little lustre. Its colours are very various, but never vivid. The blackish-brown flint is that usually found in the white chalk. It is nearly black and opaque, loses its colour in the fire, and becomes grayish-white, and perfectly opaque. Flints occur almost always in nodules or tubercular concretions of various and very irregular forms. These nodules, distributed in strata among the chalk, alongside of one another and almost in contact, form extensive beds; interrupted, indeed, by a multitude of void spaces, so as to present, if freed from the earthy matter in which they are imbedded, a species of network with meshes, very irregular both in form and dimension.

The nodules of silex, especially those found in the chalk, are not always homogeneous and solid. Sometimes there is remarked an organic form towards their centre, as a madrepore or a shell, which seems to have served as their nucleus; occasionally the centre is hollow, and its sides are studded over with crystals of quartz, carbonate of iron, pyrites, concretionary silex or calcedony, filled with pulverulent silica nearly pure, or silex mixed with sulphur; a very singular circumstance.

Flints are observed to be generally humid when broken immediately after being dug out of the ground; a property which disappears after a short exposure to the air. When dried they become more brittle and more splintery, and sometimes their surfaces get covered at old fractures with a thin film or crust of opaque silex.

Flints calcined and ground to a powder enter into the composition of all sorts of fine pottery ware.

The next important application of this siliceous substance is in the formation of gun-flints, for which purpose it must be cut in a peculiar manner. The following characters distinguish good flint nodules from such as are less fit for being manufactured. The best are somewhat convex, approaching to globular; those which are very irregular, knobbed, branched and tuberose, are generally full of imperfections. Good nodules seldom weigh more than 20 pounds; when less than 2, they are not worth the working. They should have a greasy lustre, and be particularly smooth and fine grained. The colour may vary from honey-yellow to blackish-brown, but it should be uniform throughout the lump, and the translucency should be so great as to render letters legible through a slice about one-fiftieth of an inch thick, laid down upon the paper. The fracture should be perfectly smooth, uniform, and slightly conchoidal; the last property being essential to the cutting out of perfect gun-flints.

Four tools are employed by the gun-flint makers.

First, a hammer or mace of iron with a square head, from 1 to 2 pounds weight, with a handle 7 or 8 inches long. This tool is not made of steel, because so hard a metal would render the strokes too harsh, or dry as the workmen say, and would shatter the nodules irregularly, instead of cutting them with a clean conchoidal fracture.

Second, a hammer with 2 points, made of good steel well hardened, and weighing from 10 to 16 ounces, with a handle 7 inches long passing through it in such a way that the points of the hammer are nearer the hand of the workman than the centre of gravity of the mass.

Third, the disc hammer or roller, a small solid wheel, or flat segment of a cylinder, parallel to its base, only two inches and a third in diameter, and not more than 12 ounces in weight. It is formed of steel not hardened, and is fixed upon a handle 6 inches long, which passes through a square hole in its centre.

Fourth, a chisel tapering and bevelled at both extremities, 7 or 8 inches long, and 2 inches broad, made of steel not hardened; this is set on a block of wood, which serves also for a bench to the workmen. To these 4 tools a file must be added, for the purpose of restoring the edge of the chisel from time to time.

After selecting a good mass of flint, the workman executes the following four operations on it.

1. _He breaks the block._ Being seated upon the ground, he places the nodule of flint on his left thigh, and applies slight strokes with the square hammer to divide it into smaller pieces of about a pound and a half each, with broad surfaces and almost even fractures. The blows should be moderate, lest the lump crack and split in the wrong direction.

2. _He cleaves or chips the flint._ The principal point is to split the flint well, or to chip off scales of the length, thickness, and shape adapted for the subsequent formation of gun flints. Here the greatest dexterity and steadiness of manipulation are necessary; but the fracture of the flint is not restricted to any particular direction, for it may be chipped in all parts with equal facility.

The workman holds the lump of flint in his left hand, and strikes with the pointed hammer upon the edges of the great planes produced by the first breaking, whereby the white coating of the flint is removed in small scales, and the interior body of the flint is laid bare; after which he continues to detach similar scaly portions from the clean mass.

These scaly portions are nearly an inch and a half broad, two inches and a half long, and about one-sixth of an inch thick in the middle. They are slightly convex below, and consequently leave in the part of the lump from which they were separated a space slightly concave, longitudinally bordered by two somewhat projecting straight lines or ridges. The ridges produced by the separation of the first scales must naturally constitute nearly the middle of the subsequent pieces; and such scales alone as have their ridges thus placed in the middle are fit to be made into gun-flints. In this manner the workman continues to split or chip the mass of flint in various directions, until the defects usually found in the interior render it impossible to make the requisite fractures, or until the piece is too-much reduced to sustain the smart blows by which the flint is divided.

3. _He fashions the gun-flints._ Five different parts may be distinguished in a gun-flint. 1. The sloping facet or bevel part, which is impelled against the hammer of the lock. Its thickness should be from two to three twelfths of an inch; for if it were thicker it would be too liable to break; and if more obtuse, the scintillations would be less vivid. 2. The sides, or lateral edges, which are always somewhat irregular. 3. The back or thick part opposite the tapering edge. 4. The under surface, which is smooth and rather concave. And 5. The upper face, which has a small square plane between the tapering edge and the back, for entering into the upper claw of the cock.

In order to fashion the flint, those scales are selected which have at least one of the above mentioned longitudinal ridges; the workman fixes on one of the two tapering borders to form the striking edge, after which the two sides of the stone that are to form the lateral edges, as well as the part that is to form the back, are successively placed on the edge of the chisel in such a manner that the convex surface of the flint, which rests on the forefinger of the left hand, is turned towards that tool. Then with the disc hammer he applies some slight strokes to the flint just opposite the edge of the chisel underneath, and thereby breaks it exactly along the edge of the chisel.

4. The finishing operation is the _trimming_, or the process of giving the flint a smooth and equal edge; this is done by turning up the stone and placing the edge of its tapering end upon the chisel, in which position it is completed by 5 or 6 slight strokes of the disc hammer. The whole operation of making a gun-flint, which I have used so many words to describe, is performed in less than one minute. A good workman is able to manufacture 1000 good chips or scales in a day (if the flint-balls be of good quality), or 500 gun-flints. Hence, in the space of 3 days, he can easily cleave and finish 1000 gun-flints without any assistance.

A great quantity of refuse matter is left, for scarcely more than half the scales are good, and nearly half the mass in the best flints is incapable of being chipped out; so that it seldom happens that the largest nodules furnish more than 50 gun-flints.

Flints form excellent building materials; because they give a firm hold to the mortar by their irregularly rough surfaces, and resist, by their nature, every vicissitude of weather. The counties of Kent, Essex, Suffolk, and Norfolk contain many substantial specimens of flint-masonry.

FLOSS, of the puddling furnace, is the fluid glass floating upon the iron produced by the vitrification of the oxides and earths which are present.