It takes up little room, and from its simplicity is easily and cheaply
constructed; it requires no more power to work, than the ordinary
hand-brake; it tears none of the filaments, and grinds nothing except
the boon, in consequence of the flutings of the rollers going much less
deep into each other, than the sword of the hand-brake; it prevents all
entanglements of the flax, whence in the subsequent heckling the
quantity of short fibres or tow is diminished; and it accomplishes the
cleaning of even the shortest flax, which cannot be well done by hand
machines.
The comminution of the boon of the stems, which is the object of the
breaking process, can however be performed by threshing or beating,
although in this way the separation of the woody matter from the textile
fibres is much less completely effected.
[Illustration: 418]
It is the practice in Great Britain, instead of breaking, to employ a
water-driven wooden mallet, between which and a smooth stone the flax is
laid. In that part of Belgium where the preparation of flax has been
studied, the brake is not used, but beating by means of the
_Bott-hammer_, to the great improvement, it is said, of the flax. The
_Bott-hammer_, _fig._ 418., is a wooden block, having on its under face,
channels or flutings, 5 or 6 lines deep, and it is fixed to a long bent
helve or handle. In using it, a bundle of the dried flax stalks is
spread evenly upon the floor, then powerfully beaten with the hammer,
first at the roots, next at the points, and lastly in the middle. When
the upper surface has been well beat in this way, it is turned over,
that the under surface may get its turn. The flax is then removed, and
well shaken to free it from the boon.
[Illustration: 419]
By the brake or the hammer the whole wood is never separated from the
textile fibres, but a certain quantity of chaffy stuff adheres to them,
which is removed by another operation. This consists either in rubbing
or shaking. The rubbing is much practised in Westphalia, and the
neighbouring districts. In this process, the operative lays the rubbing
apron on a piece of dressed leather, one foot square, upon her knee;
then seizes a bundle of flax in the middle with her left hand, and
scrapes it strongly with the _Ribbe-knife_ held in her right, _fig._
419. This tool, which consists of a wooden handle _s_, and a thin iron
blade _r_, with a blunt and somewhat bent edge, acts admirably in
cleaning and also in parting the filaments, without causing needless
waste in flax previously well broken.
The winnowing, which has the very same object as the rubbing, is,
however, much more generally adopted than the latter. Two distinct
pieces of apparatus belong to it, namely, the _swing-stock_ and the
_swing-knife_. The first consists of an upright board with a groove in
its side, into which a handful of flax is so placed that it hangs down
over half the surface of the board. While the left hand holds the flax
fast above, the right carries the swing-knife, a sabre-shaped piece of
wood from 1-1/2 to 2 feet long, planed to an edge on the convex side,
and provided with a handle. With this knife the flax is struck parallel
to the board, with perpendicular blows, so as to scrape off its woody
asperities. The breadth of the swing-knife is an important circumstance;
when too narrow it easily causes the flax to twist round it, and thereby
tears away a portion of the fibres. When 8 or 10 inches broad, it is
found to act best. Knives made of iron will not answer, for they injure
the filaments.
[Illustration: 420 421]
_Figs._ 420, 421. show the best construction of the swing-stock. The
board _a_ has for its base a heavy block of wood _b_, upon which two
upright pins _e e_, are fixed. The band _f_, which is stretched between
the pins, serves to guide the swing-knife in its movements, and prevent
the operative from wounding his feet. The under edge of the groove _c_,
upon which the flax comes to be laid, is cut obliquely and rounded off
(see _d_ in _fig._ 420.); thus we perceive that the swing-knife can
never strike against that edge, so as to injure the flax.
[Illustration: 422]
_Fig._ 422. exhibits the form of a very convenient implement which is
employed in Belgium instead of the swing-knife. It is a sort of wooden
hatchet, which is not above two lines thick, and at the edge _g h_ is
reduced to the thickness of the back of a knife. The fly _k_ gives force
to the blow, and preserves the tool in an upright position. The short
flat-pressed helve _i_ is glued to that side of the leaf which in
working is turned from the swing-stock; and is, moreover, fastened with
a wooden pin.
The rubbing and swinging throw off the coarsest sort of tow, by
separating and shaking out the shortest fibres and those that happen to
get torn. That tow is used for the inferior qualities of sacking, being
mixed with many woody fibres.
We may in general estimate that 100 pounds of the stalks of retted flax,
taken in the dry state, afford from 45 to 48 pounds of broken flax, of
which, in the swinging or scutching, about 24 pounds of flax, with 9 or
10 pounds of scutch tow are obtained. The rest is boon-waste. The
breaking of 100 pounds of stalks requires, in the ordinary routine of a
double process by hand, about 20 hours; and with the above described
machine, from 17 to 18 hours. To scutch 100 pounds of broken flax clean,
130 hours of labour are required by the German swinging method.
[Illustration: 423]
Mr. Bundy obtained a patent in 1819, for certain machinery for breaking
and preparing flax, which merits description here. _Fig._ 423. A A A A,
is the frame made either of wood or metal, which supports the two
conical rollers B and C. These revolve independently of each other in
proper brass bearings. A third conical roller D is similarly supported
under the top piece E of the machine. All these rollers are _frusta_ of
cones, made of cast iron. Whatever form of tooth be adopted, they must
be so shaped and disposed with regard to each other as to have
considerable play between them, in order to admit the quantity of flax
stem which is intended to be broken and prepared. The upper piece E of
the machine which carries the upper conical roller D, is fixed or
attached to the main frame A A A A by strong hinges or any other
moveable joint at G, and rods of iron or other sufficiently strong
material; H H is attached at its upper end by a joint to the top piece
E, through a hole near I, and is fixed at its lower end by another joint
K to the treadle or lever K L, which turns upon the joint or hinges M. A
spring or weight (but the former is preferable for many reasons) is
applied to the machine in such manner, that its action will always keep
the upper piece E, and consequently the upper roller D, in an elevated
or raised position above the rollers B and C, when the machine is not in
action; and of course the end L of the treadle will also be raised,
which admits of the flax to be worked being introduced between the
rollers, viz. over the two lower rollers B, C, and under the upper
roller D; such a spring may be applied in a variety of ways, as between
the top piece E, and the top or platform of the machine at N; or it may
be a strong spiral wire spring, having its upper end fastened to the
platform while its lower extremity is fixed to the rod H H, round which
it coils as shown at O, or it may be placed under the end L of the
treadle; but in every case its strength must be no more than will be
just sufficient to raise the upper roller D about two inches from the
lower rollers, otherwise it will occasion unnecessary fatigue to the
person working the machine.
The manner of using it is as follows: the upper and lower rollers being
separated as aforesaid, a small handful of dried flax or hemp stems is
to be introduced between them, and held extended by the two hands, while
the rollers are brought together by the pressure of the foot upon the
treadle L. This pressure being continued, the flax or hemp is to be
drawn backwards and forwards by the hands between the rollers, in a
direction at right angles to their axes, and eventually withdrawn by
pulling with one hand only. The foot is now to be removed until the flax
or hemp is again replaced, and each end is this way to be drawn several
times through the machine, until such ends are respectively finished.
By a succession of these operations, using the pressure of the foot upon
L, each time that the flax or hemp is introduced between the rollers,
and regulating such pressure according to the progress of the work, the
flax or hemp will soon be sufficiently worked, and the fibre brought
into a clean and divided state fit for bleaching; or if it be required
to spin it in the yellow state, it may be made sufficiently fine by a
longer continuation of the same process, particularly if worked between
the smaller ends of the rollers.
[Illustration: 423*]
Indeed, the operation may be commenced and continued for some time, with
the larger part of the rollers, and finished with their smaller ends;
and, in this point of view, the invention of conical rollers will be
found both convenient and useful; for as the flutes, grooves, or teeth,
vary in their distance from each other at all points between the large
and small ends, so it becomes almost impossible for the workman to draw
the flax or hemp through such rollers in the same track; and thus the
breaking of the boon must be much more irregular, and the fibre will be
much more effectually cleansed than it can be by the flutes, grooves, or
teeth of cylinders, or other such contrivances formerly employed;
because they would probably fall frequently upon the same points of the
fibres. If it is intended that the flax shall be bleached before it is
spun, then the second part of Mr. Bundy’s invention may be had recourse
to, which consists in moving certain trays or cradles in the water, or
other fluid used for bleaching the flax or hemp, in the manner
following, viz.: The flax or hemp, after having been broken and worked
in the machine, should be divided into small quantities of about one
ounce each, and these should be tied loosely in the middle with a
string, and in this state laid in the trays or cradles, and then be
soaked in cold soft water for a day or two, when each parcel should be
worked separately, while wet, through a machine, precisely similar to
that already described, except only that the rollers should be
cylindrical, and made entirely of wood with metal axles, and the teeth,
which will be parallel, should be similar in form to those shown in
section at Q, _fig._ 423*. Such operation will loosen the gluten and
colouring matter, for the rinsing and wringing which must follow. The
flax must then be again disposed in a flat and smooth manner, in such
trays or cradles, and once more set to soak in sufficient soft water to
cover it, in which a small quantity of soap, in the proportion of about
seven pounds of soap to each hundred weight of flax, has been previously
dissolved, and in this state it should remain for two or three days
longer, and then be finally worked through the machine, rinsed with
clear water, and wrung; which will render it sufficiently white for most
purposes.
III. _The Heckling._--We have already stated that, by the operation of
heckling, a three-fold object is proposed: 1. the parting of the
filaments into their finest fibrils; 2. the separation of the short
fibres which are unfit for spinning; 3. the equable and parallel
arrangements of the long filaments. The instrument of accomplishing
these objects is a comb-fashioned tool, called the _heckle_ or _hackle_;
a surface studded more or less thickly with metal points, called heckle
teeth; over which the flax is drawn in such a way that the above three
required operations may be properly accomplished.
[Illustration: 424 425]
The common construction of the heckle is the following: (see _fig._
424.) _Fig._ 424. is the ground plan, and _fig._ 425. is the section.
Upon an oblong plank _a b_, two circular or square blocks of wood _c_
and _d_ are fixed, in which the heckle teeth stand upright. To give
these a firmer hold they are stuck into holes in a brass or iron plate,
with which the upper surface of _c_ and _d_ is covered. Both heckles may
be either associated upon one board or separated; and of different
finenesses; that is, the teeth of the one may be thinner, and stand
closer together; because the complete preparation of the flax requires
for its proper treatment, a two-fold heckling; one upon the coarse, and
one upon the fine heckle; nay, sometimes 3 or 4 heckles are employed of
progressive fineness. The heckle teeth are usually made of iron,
occasionally of steel, and from 1 to 2 inches long. Their points must be
very sharp and smooth, all at an equal level, and must all graduate very
evenly into a cylindrical stem, like that of a sewing needle, without
any irregularity. The face of the heckle block must be uniformly beset
with teeth, which is done by different arrangements, some persons
setting them in a circle, and others in parallel rows; the former being
practised in Germany, the latter in England. The coarse heckle is
furnished with teeth about one tenth of an inch thick, one and a quarter
of an inch long, and tapering from the middle into a very fine point. In
the centre of the circular heckle is a tooth planted; the rest are
regularly set in 12 similar concentric circles, of which the outermost
is 5-3/4 inches in diameter. The fine heckles contain no fewer than 1109
teeth. Instead of making the points of the teeth round, it is better to
make them quadrangular, in a rhombus form, in which case the edges serve
to separate or dissect the fibres.
The operation of heckling is simple in principle, although it requires
much experience to acquire dexterity. The operative seizes a flock of
flax by the middle with the right hand, throws it upon the points of the
coarse heckle, and draws it towards him, while he holds the left hand
upon the other side of the heckle, in order to spread the flax, and to
prevent it from sinking too deeply among the teeth. From time to time
the short fibres or tow sticking to the teeth are removed. Whenever one
half of the length of the strake of flax is heckled, it is turned round
to heckle the other half. This process is repeated upon the fine heckle.
From 100 pounds of well-cleaned flax, about 45 or 50 pounds of heckled
flax may be obtained by the hand labour of 50 hours; the rest being tow,
with a small waste in boony particles and dust. The process is
continued, till by careful handling little more tow is formed.
Many contrivances have been made to heckle by machinery, but it may be
doubted whether any of them as yet make such good work with so little
loss as hand labour. In heckling by the hand, the operative feels at
once the degree of resistance, and can accommodate the traction to it,
or throw the flax more or less deep among the teeth, according to
circumstances, and draw it with suitable force and velocity. To aid the
heckle in splitting the filaments, three methods have been had recourse
to; beating, brushing, and boiling with soap-water, or an alkaline lye.
Beating flax either after it is completely heckled, or between the first
and second heckling, is practised in Bohemia and Silesia. Each heckled
tress of flax is folded in the middle, twisted once round, its ends
being wound about with flaxen threads; and this head, as it is called,
is then beat by a wooden mallet upon a block, and repeatedly turned
round till it has become hot. It is next loosened out, and rubbed well
between the hands. The brushing is no less a very proper operation for
parting the flax into fine filaments, softening and strengthening it
without risk of tearing the fibres. This process requires in tools,
merely a stiff brush made of swines’ bristles, and a smooth board, 3
feet long and one foot broad, in which a wooden pin is made fast. The
end of the flax is twisted two or three times round this pin to hold it,
and then brushed through its whole length. Well heckled flax suffers no
loss in this operation; unheckled, only a little tow; which is of no
consequence, as the waste is thereby diminished in the following
process. A cylindrical brush turned by machinery might be employed here
to advantage.
The boiling of flax with potash lye alone, or with lye and soap,
dissolves that portion of the glutinous cement which had resisted the
retting, completes the separation of the fibres, and is therefore a good
practical means of improving flax. When it is performed upon the heckled
fibres, a supplementary brushing is requisite to free it from the dust,
soapy particles, &c.
_Can flax be prepared without retting?_--The waste of time and labour in
the steeping of flax; the dyeing of the fibres consequent thereon, which
must be undone by bleaching; the danger of injuring the staple by the
action of putrescent water; and, lastly, the diminished value of flax
which is much water-retted, are all circumstances which have of late
years suggested the propriety of superseding that process entirely by
mechanical operations. It was long hoped, that by the employment of
breaking machines, the flax merely dried could be freed from its woody
particles, while the textile filaments might be sufficiently separated
by a subsequent heckling. Experience has, however, proved the contrary.
The machines, which consisted for the most part of fluted rollers of
iron or wood, though expensive, might have been expected to separate the
ligneous matter from the fibres; but, in the further working of the flax
no advantage was gained over the water-retting process.
1. Unretted flax requires a considerably longer time for breaking than
retted, under the employment of the same manipulations.
2. Unretted stalks deliver in the breaking and heckling a somewhat
greater product than the same weight of flax which has been retted; but
there is no real advantage in this, as the greater weight of the
unretted flax consists in the remainder of ligneous or glutinous matter,
which being foreign to the real fibre, must be eventually removed. In
the bleaching process, the water and the alkaline lyes take away that
matter, so that the weight of the bleached fibre is not greater from the
unretted than the retted flax.
3. The parting of the fibres in the unretted stalks is imperfectly
effected by the heckling, the flax either remains coarser as compared
with the retted article, and affords a coarser thread, or if it be made
to receive greater attenuation by a long continued heckling, it yields
incomparably more torn filaments and tow.
4. The yarn of unretted flax feels harder, less glossy, and rougher;
and, on account of these qualities, turns out worse in the weaving than
the retted flax. Nor is the yarn of unretted flax, whether unbleached or
bleached, in any degree stouter than the yarn of the retted flax.
5. Fabrics of unretted flax require for complete bleaching about a sixth
less time and materials than those of the retted. This is the sole
advantage, but it is more than counterbalanced by the other drawbacks
above specified.
In Mr. Wordsworth’s improved apparatus for heckling flax and hemp, a
succession of stricks is subjected to the operation of several series of
revolving heckles of different degrees of fineness, for the purpose of
gradually separating or combing the long fibres, and dressing them
smooth; while at the same time, the tow or entangled refuse portions of
the material taken off from the stricks by the heckle points are removed
from the heckles by rotatory brushes and rollers covered with wire
cards, and discharged into suitable receivers, whence it may be taken to
a carding engine, to be worked in the ordinary way.
[Illustration: 427]
The accompanying figures represent in plan and section, the heckling
machine which is made double, for the purpose of allowing two series of
stricks of flax to be acted upon at one time. _Fig._ 426. is a
horizontal view of the machine; _fig._ 427. is an end view, the whole
being represented in working order, and the respective letters of
reference pointing out corresponding parts of the machine.
[Illustration: 427]
A A are two large barrels or drums, upon the surfaces of which are fixed
longitudinally several series of brass ribs _a_, _b_, _c_, _d_, _e_,
_f_, _g_, _h_, _i_, holding heckle points. These ribs are placed at
small distances apart round the barrels, all the heckle points standing
radially from the axes, and the barrels are mounted upon axles supported
by pedestals, with plummer blocks bearing on the rails of the end
frames. B B, are two horizontal wheels or pulleys turning upon vertical
shafts, which pulleys conduct an endless chain C C C C, carrying the
holders, whereon the stricks of flax or other material intended to be
heckled are suspended.
At one end of the axle of each of the barrels a toothed wheel D D, is
made fast, and these are connected by a similar wheel E, and a pinion
F, _fig._ 427., the latter being fixed upon the axle of the driving
rigger G.
The power of a steam engine, or any other first mover, being applied by
a band and rigger, or otherwise to the axle of G, the pinion F, is
driven round, which, being in geering with the toothed wheels E and D D,
causes the heckle barrels A A to revolve simultaneously in opposite
directions, as shown by the arrows in _fig._ 427.
The stricks of flax intended to be operated upon are severally confined
between pairs of clamps _k_, fastened together, which clamps, with the
stricks, are then suspended in their respective holders H H, attached to
the endless chain C: the lower portion of the flax hanging down for the
purpose of being acted upon by the rotatory heckles, while the upper
portions are turned up in loops and confined by spring levers attached
to each carrier.
The respective holders of the clamps consist of a forked frame, with
hooks at the lower parts of their arms, which receive the ends of the
clamps _k_, that confine the strick of flax. From the upper part of each
forked frame, a perpendicular pin extends, which pins when inserted into
the sockets _l l l_, in front of the chain, form axles for the frames to
turn upon at certain periods of the operation.
On the upper end of each pin, a small arm or tappet piece _m_, _fig._
427., is fixed, standing at right angles to the face of the forked frame
of the holder H. Those tappets as the endless chain conducts the holders
along at certain periods, come in contact with stationary pins or wipers
_n n_, fixed to the guide rails _o_, on which the chain C slides; and
these wipers acting against the tappets as they pass, cause the holders
to be turned round at those periods for the purpose of bringing the
reverse side of the strick of flax on to the heckle points.
Let it now be supposed, that all the holders connected to the endless
chain have been furnished with stricks of flax, or other material to be
heckled, and that the barrels A A, are put in motion in the way
described, revolving in the direction of the arrows shown in _fig._ 427.
A pinion on the end of the axles of one of the barrels A, will drive a
train of toothed geer J K L M and N, on the axle of the latter, of which
there is a bevelled pinion taking into a bevelled wheel, turning
horizontally at the lower end of the perpendicular shaft of one of the
chain pulleys. It will hence be perceived that as the barrels go round,
such rotatory motion will be communicated to the pulley B, as will cause
it to drive the chain C forward, and by that means conduct the several
stricks of flax progressively along the barrel.
When each successive holder, with its strick of flax or other material,
is brought to the part _z_, _fig._ 426., the fibres come in contact with
the rotatory barrel, and first strike upon the series of coarse heckles
_a a_, placed upon an inclined or conical surface of the barrel, by
which means the lower ends of the flax in each strick are first acted
upon; and as it advances, the upper part, and ultimately the whole
length of the long fibres of the suspended strick are gradually brought
on to the heckles, which progressive operation prevents the long fibres
from being broken, and causes a smaller quantity of tow to be produced
than is usually taken off in any of the ordinary modes of heckling.
After the strick of flax or other material has been carried by the
travelling chain past the first inclined or conical surface _a_, of the
heckling barrel, it then comes upon the cylindrical part _b_, of the
barrel, which is also furnished with coarse heckles that penetrate and
comb down the whole pendant lengths of the fibres. But in order that
both sides of the strick of flax may be equally operated upon, the
holder is now to be turned round upon its pin or pivot, which movement
is effected by one arm of the lever or tappet _m_, (as the carrying
chain moves onward), coming against the stationary pin or wiper _n_,
which changes the position of the holder, as shown at _p_, in the
horizontal view _fig._ 426.
The under part of the guide rail _o_, upon which the chain slides, is at
this part cut away, for the purpose of allowing the holder to turn round
horizontally; and a pin or projection at the under side of the guide
rail, as the chain continues moving, acts against the side of the
carrier frame, and forces it into a position parallel with the chain.
The other side of the strick of flax is by these means brought on to the
heckles of the second inclined or conical surface of the barrel at _c_;
and the travelling chain proceeding onward, the fibres of the material
are in succession passed over and combed by the heckles of increasing
fineness, _d_, _e_, and _f_, on the cylindrical part of the revolving
barrel, until the strick having arrived at the second wiper _n_, the
frame or holder is at _q_, turned round as before, and the reverse side
of the strick, or that first operated upon by the heckles _a_ and _b_,
is brought progressively on to the heckles of increasing fineness, _g_,
_h_, and _i_; and having passed the last series of rotatory heckles, the
holders are in succession to be removed from the machine, the material
having been sufficiently dressed.
The clamps of the holders are now opened by the attendant, and the
stricks of flax or other material are taken out, and again placed
between the clamps in reversed positions, in order that the other ends
of the fibres may be operated upon. The clamps, with the stricks, are
then suspended again in the holders, the uncombed ends of the fibres
hanging down upon the heckle barrel.
In order to avoid interrupting the continual operation of the machine,
it is proposed that the strick, on its second introduction, shall be
placed in the holders on the opposite side at _y_, which is one of the
reasons for constructing a double machine, and the strick being thence
carried along by the travelling endless chain in the way already
described, the fibres will be first brought under the operation of the
coarse heckles on the inclined or conical surface of the second
revolving barrel, and then of the other heckles increasing in fineness
on the cylindrical part of the barrel, until having reached the end, as
in the former instance, the fibres of the flax may be considered to be
sufficiently dressed, and may then be withdrawn.
It may be necessary here to remark, that as different kinds and
qualities of material will require different degrees of working by the
heckles, this can be effected by varying the comparative speeds of the
travelling holders and the heckle barrels. These comparative speeds, it
will be perceived, depend upon the diameters of the wheels and pinions
by which the pulley B is driven from the rotation of the heckle barrel.
These wheels and pinions are therefore intended to be removed and
changed for others of different diameters, as circumstances may require.
It will be perceived that the faster the stricks travel through the
machine compared to the rotatory speed of the heckle barrels, so much
the less will the material be acted upon by the rotatory heckles; but as
different qualities of material must be differently operated upon,
according to circumstances, it is impossible to set out any definite
speeds or proportions of speed: that will, however, be readily perceived
by competent workmen when working at the machine.
In the process of opening the fibres of the material by the rotatory
heckles, a quantity of short or loose fibres, as tow, will be taken off
the stricks by the heckle points, and will remain adhering to the barrel
between the points of the heckles: in order, therefore, to remove this
tow, or other loose entangled materials from the heckles, several series
of brushes, or blocks, with bristles, are affixed longitudinally to
rotatory barrels Q Q.
These brush barrels are mounted parallel to the heckle barrels upon
axles, supported in plummer blocks affixed to brackets extending from
the end frames of the machine. Those parts of the brush barrels which
are opposite to the cylindrical portions of the heckle barrel are
cylindrical, and those parts which are opposite to the bevels are
contra-bevelled, or made as frustums of cones reversed, or in an
opposite angle, as _r_, _s_, so as to run parallel to the inclined
surfaces of the heckle barrels _a_ and _c_.
Upon the periphery of these barrels Q Q, ribs or blocks, with bristles
or brushes, are fixed longitudinally, at suitable distances apart, the
bristles all standing radially from the axle, and taking into the points
of the heckles.
Rotatory motions are given to the brush barrels Q Q, by bands passing
from the riggers at G, over pulleys R R, fixed at the end of each of the
axles of the brush barrels. Hence, it will be perceived, that the
barrels Q Q will revolve in opposite directions to the heckle barrels,
and with sufficient speed to enable the brushes to pass through between
the points of the heckles, and in so doing, to remove the tow or other
loose matter therefrom.
The tow or other loose fibrous material collected upon the brushes is
transferred thence on to wire cards placed round the periphery of the
barrels S S, which barrels are mounted upon axles parallel to the brush
rollers, and turn in plummer blocks upon brackets, extending from the
end frames of the machine.
These barrels are cylindrical, and covered with sheets of wire cards at
those parts which are opposite to the cylindrical portions of the brush
barrels, but those portions of the barrel S, which are opposite to the
bevelled points _r_ and _s_, of the brush barrels, are bevelled or made
conical at _t u_, to fit or correspond with the inclined surfaces _r_
and _s_; these are covered with sheets of wire card also.
Rotatory motions are communicated to the card barrels S S, by bands from
the pulley T, fixed on to the side of the toothed wheel M, (see _fig._
427.) which band drives similar pulleys V V, mounted upon studs fixed in
the end frame. Upon the side of each of these pulleys V V, a pinion _t_
is fixed, which pinion takes into the teeth of the wheel W, on the end
of the axle of each of the card barrels S S; by which means such slow
motions are given to the barrels S, as will allow the brushes of the
barrels Q to comb off, and deposit the tow or other fibrous material
upon the wire cards as they revolve, and from whence it is to be removed
by a doffing comb, and let fall into any convenient receptacle below, in
the same way as in ordinary carding engines.
The doffing combs, X X X, are formed to the shape of the card barrels,
and are attached to straight bars extending along the machine on both
sides, which are supported at their extremities by levers Y Y, vibrating
upon fulcrum pivots at _w w_. To these levers perpendicular rods Z Z are
connected by joints, and the lower end of each of these rods is attached
to an eccentric disk, roller or crank _x x_, on the axle of the brush
barrel; whence it will be perceived that by the rotation of the
eccentrics _x_, the levers Y will be made to vibrate and strike off, or
doff the tow or other material from the card barrels, in a similar
manner to the operations of the doffing comb of an ordinary carding
engine.
Mr. Evans’ patent improvements in machinery for preparing and dressing
flax and hemp apply, first, to the operation of scutching, swingling, or
beating away the boom or woody particles of the rind which covers the
flax, or hemp, in its rough state; and, secondly, to the subsequent
operation of heckling, combing, or opening of the fibres of the material
preparatory to spinning it into yarns.
[Illustration: 428 429]
_Fig._ 428. represents the scutching or swingling machine, in different
positions. _Fig._ 428. is an end view of the machine in operation;
_fig._ 429. is a front view of the same. The essential parts of the
machine, and those in which the invention especially consists, are two
pairs of revolving beaters or scutchers, each formed by long ribs or
blades mounted upon arms. The blades of the beaters _a a_, may be made
of ribs of hard wood, or other suitable material, broad but thin, and
slightly rounded on their edges, to prevent their cutting the fibres of
the flax or hemp when they strike it. The two blades are placed parallel
to each other, and mounted upon a hexagonal frame, the arms _b b_
inclining or forming obtuse angles with the blades, and from the middle
of the arms short axles _c c_, extend, upon which the beaters revolve.
The axles of both pairs of beaters are mounted in plummer boxes, bearing
upon horizontal rails at the ends of the machine, as shown in _fig._
428., and are at such distance apart as will allow of the arms and the
beaters of each pair passing alternately within those of the other pair
as they revolve in opposite directions, which they are enabled to do
without coming in contact, in consequence of the inclination of the
arms.
On the axle at one end of each pair of beaters a toothed wheel _d_, is
affixed, and these wheels being of similar diameters, and taking into
each other, cause the beaters to revolve with similar speed in opposite
directions, rotatory motion being given to them by a band and rigger
fixed upon one of the axles; and in order that the beaters in revolving
may not come in contact as they pass, the positions of the two pairs are
so arranged that the blades of one shall be in a perpendicular
situation, while those of the other are horizontal.
The rind of the flax or hemp having been previously broken by any of the
ordinary modes of performing that operation, small bunches or stricks of
the material are spread out, and their ends confined between the jaws of
clamps or holders.
[Illustration: 430 431]
These clamps or holders differ considerably from the clamps which are
commonly used. I shall therefore particularly describe their
construction, before showing them in operation. _Fig._ 430. and 431. are
views of the clamp in two different positions; _a_ and _b_ are two
boards united together by a hinge _c_, at top, which of course allows
them to shut and open. The lower parts, forming the jaws of the clamps,
are made with teeth or indentations, between which parts the ends of the
flax or hemp are securely held when the clamps are brought together; _d
d_, are two pieces projecting from the board _b_, at the end of each of
which is an eye shown by dots, and at the back of the board _a_, (see
_fig._ 430.,) there is a double armed lever _e_, turning upon a fixed
pin _f_, which lever carries two circular wedges _g g_. These wedges
pass into the eyes of the pieces _d d_, when the clamps are closed, and
hold them fast. There is a segment ratchet _h_, at the upper part of the
board _a_, which turns upon a stud _i_, and is pressed downward by a
spring _k_. This ratchet receives the end of the lever _e_, and
consequently keeps the circular wedges firm in the eyes, which hold the
clamps securely together, and prevents their opening by the shaking of
the machine.
When it is required to open the clamps, the ratchet _h_ must be raised,
and the lever _e_ pushed aside by its handle _l_, which draws the
circular wedges _f_ from the eyes of the pieces _d d_, and the boards of
the clamps immediately separate. For the convenience of suspending the
holders in the machines, a piece of sheet iron _m_, is bent at right
angles, and fastened to the back of the board _b_, as seen in _fig._
431., forming a groove by means of which the holders are enabled to
slide into the machine and hang there.
These clamps or holders are, when charged with the material, placed in
the scutching machine, as shown at _e e e_ in _figs._ 428. and 429.,
bearing upon the edge-rail or bar _f_. The beaters are now made to
revolve in the manner already described, by which the edges of the
blades will strike against the pendent stricks of flax or hemp
alternately on each side, and beat off, scutch or swingle the boom from
the material, and render it fit for the operation of heckling which is
to follow.
The whole machine is encased with boards, to prevent the inconvenience
arising from dust, and an apparatus might be adapted with a blower to
conduct away the dust created by the machine, and to discharge it out of
the building.
In introducing these stricks of flax or hemp into the machine, the
holder is placed upon the projecting end of the bar or edge-rail _f_,
and is thence slidden into the machine; and after the material has been
sufficiently scutched or swingled, the holders with the stricks are
removed through the top of the machine, and others successively
introduced at the end, and pushed along the rail.
If, however, it should be thought desirable, the stricks may be
progressively carried through the scutching machine, and delivered into
a similar edge-rail in the heckling machine, there to be operated upon
in the way about to be described, by which means the whole process of
scutching and heckling may go on without interruption.
[Illustration: 432]
_Fig._ 432. represents the heckling or combing machine by which the
fibres of the material are to be opened, and the tow removed. It is a
transverse section, taken nearly through the middle, in a vertical
direction. Perpendicular standards form the ends of the machine, which
are connected together by longitudinal rods or bars secured by nuts. The
heckle points intended to act upon the flax are mounted in the frames
_a_, _b_, _c_, and _d_, and the stricks of flax held in the clamps _e_,
_e_, _e_, as described, are suspended from the bar or edge-rail
extending through the machine.
In order to render the principles of this machine and its mode of
working evident, it may be desirable to show in an abstract form the
manner in which the heckles are brought into operation upon the flax,
and for this purpose two diagrams are delineated in _figs._ 433, 434.
Suppose two sets of combs or heckle points be mounted upon frames _a_
and _b_, as in these figures, each frame being moveable by means of
cranks _c_, _c_, and _d_, _d_, connected in such manner that they both
turn with the same speed in opposite directions, it is evident that
every part of the frames and combs will move in circles corresponding to
those described by the cranks; the points of the combs travelling in the
directions of the arrows, and in circles represented by dots.
[Illustration: 433 434]
During this movement, whilst performing the first descending quarter of
the circle, the cranks bring the frames together as in _fig._ 433. They
begin after this to separate in describing the second descending
quarter, and come to the position _fig._ 434., when, continuing to
revolve, they move further from each other in describing the first
ascending quarter of the circle, and arrive at the position where the
distance is the greatest; lastly, they describe the second ascending
quarter returning to the third position. If, therefore, a strick of flax
be suspended between the two sets of combs as in _fig._ 433., and the
rotatory motion be continued for a sufficient length of time, the flax
will be combed in the whole length which is submitted to the actions of
the combs, although the points severally have only operated in very
small space.
Such a system of combs or heckles would make a very good and simple
heckling engine, if it were not for the inconvenience experienced by the
points dragging some of the fibres with them when withdrawing from the
flax, which would produce a great waste of material; and to obviate this
it would be necessary to introduce some contrivance for clearing the
points, which must be attended with considerable complication. The plan,
however, of the present improved engine, affords the means of producing
the same effect by more simple and efficient means.
[Illustration: 435 436]
There are two series of combs, see _fig._ 435., attached to two movable
frames represented at _a_ and _b_. Each frame is formed by vertical bars
_a b_, with lateral branches or arms, which carry the heckle points. The
branches or arms are parallel, and at equal distances apart, but fixed
in such positions in each frame that they may occupy the intervening
space when the frames are brought together as _fig._ 436. The frames are
put in motion by means of revolving cranks to which they are attached,
as shown in _fig._ 436., and when the cranks turn upon their axes, the
branches of one frame pass between those of the other without touching.
This forms what may be called a set of combs; but one of the improved
machines contains two such sets, the points of the combs of one set
being opposed to the points of the combs in the other set.
The way in which the series of combs that compose one set act upon the
flax, is shown in the side view, _fig._ 435. When the cranks are nearly
vertical, the points of both frames are away from the flax, but as the
cranks move round in the direction of the arrows, the frames come into
another position, and it is then that the points or heckles of one of
the frames _a_, begin to penetrate the flax, and descending they comb or
divide its fibres. The rotation of the cranks continuing, the two frames
_a_ and _b_ come into the position shown at _fig._ 435., the points of
the frame _a_, withdrawing from the flax, and those of the frame _b_,
approaching and pushing the fibres off from the former, which are now
combed by the descending stroke of the points.
It will hence be perceived that as the combs of the frame _a_ and _b_,
respectively advance, they will push forward the whole of the strick of
flax, and render it impossible for the fibres to be raised and
entangled, as each frame in advancing clears the fibres from the points
which preceded it.
[Illustration: 437]
A single set, however, of such combs or heckles acting only on one side
of the flax, would but imperfectly perform the operation of opening its
fibres; it is therefore necessary, in order to accomplish the desired
object in the most effectual way, that two such sets of combs or heckles
should be brought to act on opposite sides of the strick of flax, which
may be done in the manner shown in the figures. The cranks of the two
opposite sets of comb-frames or heckles _a_, _b_, and _c_, _d_, are
connected by a pair of toothed wheels _e_, _f_, as _fig._ 437., or by
four toothed wheels, by which the heckles are actuated at once, the two
sets moving in opposite directions, but with similar speeds, and the
combing or heckling of the material will go on in the way shown in the
figure last indicated.
Thus far I have considered only two frames of combs or heckles
constituting a set, as acting upon each side of the strick of flax; but
in order to perform a greater quantity of work, several sets may be
mounted in one machine, working alongside of each other, extending over
the breadth of the machine. The combs may then be supported upon three
frames, of which the middle one may have branches or arms extending upon
both sides, and the other two frames branches extending inwards only. To
drive the frames so arranged they must be connected to treble cranks.
Such is the principle of the improved machine for combing or heckling,
exhibited in the several figures of which I now proceed to describe the
particular construction. The machine or engine, _fig._ 432., has four
sets of combs, acting both at the back and front of the flax; _a b_ are
the front set of combs, and _c d_, the back set of combs; _e e e_, are
the clamps holding the stricks of flax previously scutched, which clamps
hang upon the edge-rail. The comb frames are attached at top and bottom
to the cranks _g g_, which are all connected by toothed geer, and driven
by a band and rigger.
The combs or heckles being put in motion in the way described, act upon
the suspended stricks of flax, and upon their fibres, as explained;
which stricks are progressively conducted through the machine by their
clamps sliding upon the edge-rail through the agency of the endless
chain, to which the clamps are severally attached, by a hook falling
into one of the links. The chain is driven by a spur wheel upon the axle
of a bevel wheel, which receives a slow rotatory motion through a bevel
pinion on the axis of a similar wheel, actuated by another pinion on the
end of the upper crank axle. By these means, clamps, with the stricks of
flax placed on the edge-rail, are slowly carried through the machine,
when the flax will be gradually acted upon first by heckle points of a
coarse kind, set wide apart, and ultimately by finer points set near
together; after which, the clamp with the strick of flax is discharged
from the machine, at the reverse end of the edge-rail. But should the
workman neglect to remove the holder or clamp, when it arrives at the
end of the rail, the machine would be stopped by means of a jointed
lever, having a fork at its end, which pushes the band from the fast
rigger on to the loose one, and throws off the driving power.
As the combs or heckles, in acting upon the flax to divide its fibres,
tear parts of the fibres, and reduce them into tow, the downward motion
of the heckles brings the tow with them out of the flax, which is
deposited between two fluted rollers _p p_, _fig._ 432., and is by them
conducted down to the large drum _q_, where it becomes lapped in two
endless sheets round the periphery of the drum; the one of coarse tow,
the other of fine, the adhesion being assisted by a pressing roller _r_;
and when a quantity of the tow has been thus accumulated round the
periphery of the drum, it may be removed thence by cutting it off in
sheets. The fluted rollers, and also the large drum, are driven by geer
bands.
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:--