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in equal or in nearly equal quantities on both sides. For ex-
ample, if a twill inclines to the left (thus\) when viewed
obversely, it will incline to the right (thus /) when viewed on
the reverse side, albeit the direction of twist in both warp and
weft remains the same. Therefore the direction of twill in
relation to the direction of yarn twist is different on each side
of the fabric, with the result that the twill appears to be more
prominent on one side than on the other. In this case, however,,
the influence exerted by the deflection of the warp line out of
a straight course between the breast beam and back rest of a
loom (to spread the warp ends and thereby obtain what is
termed "cover" in cloth) will be a contributory factor affecting



TWILL AND KINDRED WEAVES. 33



Fig. 'y^. — yhowiDg tlie Face Side of -2 - Twill Cloth of Coarse Texture, produced
from Folded Warp and Weft twisted siuistrally, or Weft- way (when folded),
and with the Twill produced upward from left to right, or dextrally.
(Note the prominence of Twill.)






Fig. 56. — Showing the Reverse Side of the piece of Twill Cloth represented by
Fig 55. (Note the peculiar inclination of Warp Threads from a straight
course, and its effect in subduing the Twill.)

3



34 GRAMMAR OF TEXTILE DESIGN.

the relative prominence of twill on both sides of a fabric. This
circumstance, however, does not entirely account for the differ-
ence between the face and back of a twill cloth, otherwise no
difference would be manifest between the same twill produced
to the right and to the left in different parts of the same fabric.

What actually occurs, is that the series of ridges and furrows
in a twill fabric are more sharply defined and pronounced if they
incline in the opposite direction to the twist in yarn with which
the ridges of twill are formed ; and per contra, the twill will be
less prominent if the twill and yarn twist lie in the same
direction.

§ 23. This peculiar and interesting phenomenon in twill and
allied weaves has occasionally engaged the attention of textile
experts who have sought to discover its origin ; and although
various theories have been put forward as probable explanations
of it, its true cause is still a matter for conjecture, and cannot
therefore at present be definitely stated.

According to one theory, the phenomenon just referred to is
attributable to the effect produced by the reflection of light at
different angles from the fibres composing the threads, accord-
ing to the direction in which the fibres lie in relation to the
direction of twill. This may partly account for the different
effects, but it is apparently not the chief factor, as may be easily
demonstrated by taking a piece of cloth in which the same twill
is produced in both directions, in different parts, and viewing it
in a neutral or well-diffused light, when a decided difference
will be observed between the twill incHned to the right, and
that inclined to the left. The twill in the opposite direction to
the twist of yarn will be more distinct than that in the same
direction as yarn twist. It would appear, therefore, that the
difference is caused either partly or entirely by some influence
exerted by the direction of twill upon the twist of yarn. This
preconception forms the central feature of another theory based
on the assumption that since the spirality of a spun thread is an
artificial and not a natural property of such a thread, the fibres
composing it subsequently tend, under favourable conditions
to recover their original straight and free condition, thereby
causing the thread to untwist, especially when it is subjected to



TWILL AND KINDRED WEAVES. 35

tensile strain. Hence it is argued that during weaving, when
the respective threads are under tension, they tend to untwist in
cloth, and consequently roll slightly out of their original per-
fectly straight course, and assume a more or less oblique in-
clination between the points where they intersect with other
threads, unless means are adopted to prevent or check such
tendency by producing the twill in the opposite direction to that
of yarn twist.




Fig. 57.— Showing a Thread Spun Avith'ajRight-hand Twist, or " Twist- way ".

§ 24. The different effects of the same twill weave produced
in opposite directions in the same fabric are exemplified in a very
striking manner by Figs. 55 and 56, which represent portions
of the face and back, respectively, of an actual example of grey
cotton two-and-two twill cloth, containing thirty-five warp ends
per inch of 4/6's yarn ; and twenty-two picks per inch of 4/10's
yarn. The single strands of yarn composing the folded threads of
both warp and weft are spun " twist " way, i.e., dextrally, with the
twist or spirality extending upward from left to right, thus /



36



GEAMMAE OF TEXTILE DESIGN.



(when the thread is viewed either suspended vertically, or ex-
tending from the observer) and as indicated in Fig. 57 ; but the
doubling twist of the folded thread is in the opposite direction to
that of the single-yarn twist (in accordance with usual practice in
doubling spinning), namely " weft " way, i.e., sinistrally, with
the twist inclining from right to left, as indicated in Fig. 58.
The twill on the face of cloth incHnes to the right, and therefore
opposes the direction of twist in the warp ends, which are both




Fig. 58. — Showing a Thread Spun with a Left-hand Twist, or "Weft-way'



coarser and more numerous than picks of weft, and are con-
sequently more assertive than these ; hence, the twill is much
more prominent on the face than at the back of cloth, where it
inclines in the same direction as the warp twist.

§ 25. According to the second theory explained in ^ 23, a
twill will be more pronounced if it is produced in a direction
whereby the tendency of threads to untwist and roll out of their
straight course will be prevented or checked. Therefore, if the



TWILL AND KINDEED WEAVES.



37



■untwisting of threads that will form the ridges of twill causes
them to incline to the left, the twill should be produced to the
left also, so that the threads will support each other, at the
extremities of the float, on those sides towards which they tend
to roll. If, however, the threads are left unsupported at those
parts, as would occur if the twill were produced in the same
direction as the twist, their tendency to untwist and roll would
be unchecked, and the floats would assume a slight list in the
opposite direction to the twill, as clearly manifested in Fig. 56.




Fig. 59. — Showing the direction of Twill in a Warp- face Twill Fabric with Warp
Yarn Spun "Twist-way," to produce a prominent Twill.



§ 26. Whatever may be the influential factor in determining
the relative prominence of twills, it may be repeated that those
produced in the opposite direction to that of the twist in yarn
will be more pronounced than if both are in the same direction ;
and so long as this dictum is observed, it is immaterial in what
direction a twill may incline, or in which direction yarn is
twisted during spinning. Therefore, if a bold warp twill is
produced from yarn spun " twist " way (Fig. 57), the twill



38



GEAMMAE OF TEXTILE DESIGN.



should incline upward from right to left, as represented in Fig.
59. If a weft twill is required from yarn spun " weft " way
(Fig. 58) the twill should incline upward from right to left also,
as in Fig. 60. (This may at first appear inconsistent, until it is
observed that the direction or spirality of twist in a spun thread
inclines in opposite directions when placed at right angles to
itself, as indicated by arrows in Figs. 57 and 58). Again, if a
twill weave having warp and weft displayed in equal or nearly
equal quantities on both sides of cloth is produced from warp




Fig. 60, — Showing the direction of Twill in a Weft-face Twill Fabric with Weft
Yarn Spun "Weft-way," to produce a prominent Twill.

spun *' twist " way and weft spun " weft " way, the twill should,
in this case also, incline upward 'from right to left, as indicated
in Fig. 61. If, however, a weft twill is required from yarn
spun "twist" way, or a warp twill from yarn spun "weft"
way, the twill should incline upward from left to right, as in
Fig. 62.

2. Zigzag or Wavy Twills.

§ 27. This subdivision of twill weaves comprises those in
which the direction of twill is frequently reversed, to produce a



TWILL AND KINDKED WEAVES.



39




Fig. 61.— Showing the direction of Twill in a Fabric having a Warp and Weft
Face, and with Warp Yarn Spun " Twist- way," and Weft Yarn Spun
"Weft-way," to produce a prominent Twill.




Fig. 62.— Showing the direction of Twill in a Weft-face Twill Fabric with Weft
Yarn Spun " Twist-way," to produce a prominent Twill.



40



GRAMMAR OF TEXTILE DESIGN.



series of waves running horizontally, obliquely or vertically,
according to the particular manner in which the reversals are
made. Any regular twill weave may be employed in the de-
velopment of wavy twills ; also the twill may be reversed at
regular or irregular intervals on either warp ends or picks,
according to the effect desired. It should be observed, however,
that, as a rule, the best effects will be obtained by reversing the
twill on that series of threads which will be in greatest abund-
ance on the face of the fabric. Thus, if warp preponderates
over weft, the waves should reverse on warp ends ; and if weft
preponderates over warp, they should reverse on picks of weft,




Fig. 63.



Fig. 64.



provided of course that the preponderating threads are not in-
ferior in either numbers or quality. By adopting this course,
long floats, which would otherwise occur at all points where the
twill is reversed, and which look like imperfections in cloth, are
avoided, and sharper wave crests and furrows are produced.
The accompanying examples of wavy twills are uniformly based
on the regular twill weave represented in Fig. 63, which repeats
on eight warp ends and picks, and requires eight shafts of healds
to weave it, with warp ends drawn through them with a
"straight-over" draft, as indicated above the design. This
weave has warp preponderating over weft in the ratio of five of
warp to three of weft, thus -j-^ = i-



TWILL AND KINDEED WEAVES.



41



Figs. 64, 65 and 66 are horizontal wavy twills produced by
reversing weave Fig. 63 at regular intervals of eight, twelve and
sixteen warp ends, thereby causing them to repeat on sixteen,
twenty-four, and thirty-two warp ends, but only eight picks,
respectively. As indicated by the drafts immediately above
them, each design requires only eight shafts of healds (as does
the original weave) for its production ; but they would each
require a different set of healds in consequence of the different
methods of drafting warp ends through them. If the same
weave (Fig. 63) were employed to produce similar wavy effects
to those of Figs. 64, 65 and 66, but vertically instead of hori-





J 1 1 J t

Hh 1 rijfeH . 1 . ^Hicjli . hl -ftp 1 '' -t3tlP 1 ^ ■Hh- ' 1 'BE - r 4


.••jT yj^ •K-.mm .v .v ■«». "Sts


^.'^>hym'f.^.^\.:^%^>



Fig. 6f



Fig. 66.



zontally, the draft shown above Fig. 63 would answer, and the
healds would be raised in consecutive order, forward and back-
ward alternately, for eight, twelve, and sixteen picks, respectively,
thereby causing the designs to repeat on twice that number of
picks. This latter course would involve the use of dobbies or
other shedding devices capable of weaving designs repeating on
a large number of picks ; whereas, in the former case, the designs
could be woven by means of eight-pick tappets.

§ 28. Figs. 67, 68 and 69 are variegated wave effects produced
by reversing the twill at irregular intervals of warp ends, so as
to produce large and small waves in a horizontal direction. In
Fig. 67 the twill is reversed at intervals of four, eight, and four



42



GEAMMAK OF TEXTILE DESIGN.



warp ends continuously. In Fig. 68 the intervals are eight,
four, and eight warp ends continuously : and in Fig. 69 they
are four, eight, four, eight, and four warp ends continuously.




Fig. 67.



By thus reversing for an equal number of warp ends in both
directions, the waves assume a horizontal course so far as one
or more than one repeat of the pattern is concerned. Only




'IG. 69.



eight healds are required to produce these designs ; but the
drafting of warp ends through them must be as indicated above
the respective designs. This causes the patterns to repeat
on thirty-two, forty, and fifty-six warp ends, and eight picks,
respectively.



TWILL AND KINDRED WEAVES,



43



§ 29. Figs. 70, 71 and 72 are wavy effects in which the
waves are produced obHquely by reversing the twill uniformly
at shorter intervals in one direction than in the other. The




Fig. 70.



Fig. 71.



obliquity of the waves may be more or less acute according to
the system of reversing, and the intervals at which the reversals




Fig. 72.



occur, as seen in the examples given. In Fig. 70 the intervals
are eight and four warp ends alternately, throughout. In Fig.
71, a more acute obliquity is obtained by reversing the twill at



44 GEAMMAR OF TEXTILE DESIGN.

intervals of eight, four, eight, four, and four warp ends con-
tinuously ; and in Fig. 72 a still more acute slant is produced
by reversing the twill at intervals of eight, four, four, and four
warp ends continuously. These designs repeat on eight picks,
and require eight shafts of healds, with warp ends drafted as
shown, to produce them. In the development of wavy twill
designs, the relative sizes of waves are determined by the
number of threads on which the twill is produced in any
direction.

3. Rearranged Twills.

§ 30. Eearranged twills are those evolved by the rearrange-
ment of either warp ends or picks of any regular or continuous
twill weave, according to some definite plan. For example,
consecutive threads of a given weave may be redistributed at
regular intervals of two or more threads apart, as required ; or,
as an alternative method, threads of a given weave may be taken
at intervals of two or more, and arranged consecutively to form
a new design.

Satin Weaves.

The simplest application of this system of rearranging twill
weaves obtains in the development of what are known as '* satin "
weaves, produced by rearranging simple continuous warp-face
or weft-face twills (as represented in Figs. 31 to 35, and 37 to
41 respectively), according as warp-face or weft-face satin
w^eaves are required. Satin weaves are characterised by an
even and smooth surface, of either warp or weft, resulting from
a perfectly regular distribution of intersections of those threads.
They constitute one of the most useful varieties of weaves and
are extensively employed, in conjunction with other weaves, as
an element or component part of elaborately decorated fabrics,
as well as in the production of piece-good fabrics constructed
entirely on the basis of one of such weaves. Although satin
weaves are (for convenience of classification) generally regarded
as derivations or rearrangements of simple continuous twill
weaves, it will be seen that they bear no resemblance whatever
to that class, but are entirely different in respect of the distribu-
tion of intersections.



TWILL AND KINDEED WEAVES.



45



123456789 10




2 3 4 56 7 8 9 10




123456789 10 123456 739 10











Fig. 73. — Showing the Construction of Satin Fig. 74. — Showing an Alternative Method

Weaves. of Constructing Satin Weaves.



46 GRAMMAR OF TEXTILE DESIGN.

§ 31. In the production of satin weaves, the intersections or
binding points of warp and weft should be distributed as freely
and far apart as possible, on such number of threads as are to
constitute one repeat of the pattern. The more perfectly such
distribution is accomplished, the more perfect will be the even-
ness and smoothness of cloth. The rearrangement of any con-
tinuous twill w^eave, to produce either a simple satin weave, or
other design having a satin basis, may be made in accordance
wath an arithmetical formula to obtain the " interval of selection "
w^hich determines the positions of intersections or binding points
on consecutive threads of either series for any size of satin
weave, excepting those contained on four and six threads (which
are imperfect satin w^eaves). Having decided the number of
threads on which to construct a satin weave, the *' interval of
selection " may be either of two complementary numbers whose
sum equals the whole number, but which have no common
measure.

Exani]}le : It is required to construct a ten-end satin weave.
The only two complementary divisions of ten, which have no
common measure, are three and seven ; therefore either three or
seven may be taken as the " interval of selection," and the
intersections disposed at intervals of three or seven threads of
either series, on consecutive threads of the other series.

The application of this formula will be easily understood by
reference to Fig. 73, where a ten-end w^eft-face satin (B) is pro-
duced by transposing the threads of a ten-end weft-face twill (A)
in the manner indicated ; namely, by disposing say every third
warp end in A, in consecutive rotation to produce B. Or the
same result is virtually attained by the method shown at Fig.
74, where consecutive w^arp ends in A are redisposed at intervals
of three threads to produce B. The only difference between
Figs. 73 and 74 is in the reversed sequence of intersections.
Again, similar results would obtain by rearranging picks instead
of warp ends ; and also by adopting the complementary number,
seven, as the interval of selection.

Some numbers, as five, eight, ten, and twelve, each permit
of only two complementary numbers which have no- common
measure ; w^hilst some have four, and others more than four,



TWILL AND KINDRED WEAVES.



47



numbers which have no common measure. As regards those
which have four minor numbers, a similar distribution of inter-
sections will occur, whichever of the four is selected as the inter-
val ; but as regards those numbers which offer a greater choice
of intervals, the selection of the best interval is entirely a matter



emu



UWIUW



i:::::i:



Fig. 75. — 4-end.



Fig. 76.



-end.



Fig. 77. — 6-end.



of judgment and not of rule. In such cases it is better to con-
struct weaves based on each interval, and select that which gives
the most perfect and regular distribution of intersections.

^32. The following table shows the intervals of selection for
the construction of satin weaves on five, and seven to twenty-



i. I. I. .1.. I.. !

.1 — __i — ._■ — .-■ — ..__■ — .__■ — |..i_



i jH|y [ UH| :='ffi

!:iii:;E!::i::jE!;!i

l y I M H l yi n H l y M



Fig. 78.— 6-end.



Fig. 79.— 7-end.



Fig. 80.— 8-end.



two threads. Instead of the numbers given, their complements
may be taken. Where two intervals are given, each of them
or their complements will produce similar results. Where more
than two intervals are given, the number or numbers shown in
heavy type (or their complements) will give the most perfect dis-
tribution of intersections ; and those weaves indicated in italics
are the only satin weaves (included in the following table) in
w^hich the distribution of intersections is absolutely perfect : —



48



GEAMMAE OF TEXTILE DESIGN.



Table of Intervals of Selection for the Construction
OF Satin Weaves.



5-end satin — 2.

7-end satin — 2, 3.

8-end satin — 3.

9-end satin — 2, 4.
10-end satin — 3.
11-end satin— 2, 3, 4, 5.
12-end satin — 5.
13-end satin— 2, 3, 4, 5, 6.
14end satin — 3, 5,



15-end satin — 2, 4, 7.
16-end satin — 3, 5, 7.
17-end satin— 2, 3, 4, 5, 6, 7,
18-end satin — 5, 7.
19-end satin— 2, 3, 4, 5, 6, 7,
20-end satin— 3, 7, 9.
21-end satin— 2, 4, 5, 8, 10.
22-end satin— 3, 5, 7, 9.



8,9.



— — . — I — ■ I 1 — i.._.

.-I — _ — I — I I i_^._ I — 1 —

:::!:::■ ;:::i::: !::::::: ::i::!::::::i2:::;::::::i:::-: :!:::! :::;::

:■::::- = ::i:::! -;::■:::: ::::-::! ::!:::;::■:::::: I :::;::!:::i :::-::!:

— . — I — . — ■ — I ■ — — I — I

. - -I — __i — I I i_. I — ...

wiiiyiiFiiMyimiMiiiiumiiiiiyiwiinMiHMiwiiU H — ' -



Fig. 81.— 9-end.



Fig. 82.— 10-end.



Fig. 88.— 11-end.



Figs, 76 and 79 to 94 are weft-satin weaves constructed in accordance
with the above table. Fig. 75 is the so-called four-end satin weave ; and
Figs, 77 and 78 are alternative arrangements of a six-end satin weave.
That shown in Fig. 77 is preferable to that shown in Fig. 78, as it gives
a more perfect distribution of intersections.






:::b::::!::j::::i::::::::j:::[: :::i::::j:::!

_■ . — ■ I -I — I —

::::i::::!::J±:i::::::::!::::i::::i:::::::
::j::::i:: :|:±:::::::::::i::::;:::!::::i::

-fV H- +tti:::: ii JM TII : Mil IHIII y II II I M l



Fig. 84.— 12-end.



Fig. 85.— 13-end.



Fig.



-14-eud.



" Corkscrew " Twills.

§ 33. Corkscrew twills constitute a variety of rearranged twills

largely employed in the production of worsted garment fabrics,

for which they are eminently suited, as they are capable of

producing firm and compact textures of great strength, warmth



TWILL AND KINDRED WEAVES.



49



and durability. Perfect corkscrew weaves are characterised by
a somewhat subdued twill formation, with either warp or weft



' T fM f wrffl i i ri Jiii y i i iH i i inj ii ii i ni ii u i i ti ii H ii F s

;M;;:i;;:i:E!;;;!;:;::;EE;i::;;g:!;;EE;K:E;E:!;E:!;:EEjE::i;EE!

::E;!iEEi:EE;EE:EEE!EEE;!EEEE!;;EE;iEiE;!:E;E;E;iEEE!E;!!EEE;j;EEiEE

y I II 1 1 l l-j-' n I l y M I H II y I +n-i+ + — ■ — ■ - -'



Fig. 87.— 15-end.



Fig. 88.— 16-end.



Fig. 89.— 17-end.



only visible on the face of the fabric, and are usually constructed
on an odd number of warp ends and picks. The latter circum-



1 _ _ _.. 1 .__ TOT" TT


_,__.: . ■-.-.


::i::::::::::i: :■-■■- .■: " i








:I::::::::::i::: ::::::±::::::': :::i:::: ::::::::::i::::: :±::::. :::








::i:i::::. :::;:: ::::::::::::::: ::::i::: ::::::::::::::: :ji:::": :■■


, 1 — 1 ::::: I :::::; i::


::±::!: ::;::::: :i::::± :::!:::: i::::::: ::::::::::::!::: :::i::::::::








:::::::i:::: ::::::± — " i " i


n n M M u n






::±::::±:::±:::::::± :::::::: :::::i:::::::::::::::±:::::±:::::



Fig. 90.— 18-end.



Fig. 91.— 19-end.



Fig. 92.— 20-end.



stance arises from the particular method of constructing them,
namely, by rearranging either series of threads of any suitable



1 u H ti n u ti ffi

::::j::::!:J::::i::::::i::::::::j:::-::::::
::::::: :::!:: :: ::n:::: :::::::i:::::: iiji::'



Fig. 93.— 21-end.



Fig. 9J.— 22-end.



continuous twill weave at intervals of two, or alternately ; and
since two is not a measure of odd numbers, an odd number of

4



50



GKAMMAR OF TEXTILE DESIGN.



threads are required for one repeat of the pattern, in accordance
with the principle governing the construction of satin weaves,
as explained in § 31.




Fig. 95. — Showing the Construction of Warp-face Corkscrew Weaves.

Warp-face corkscrew weaves may be produced by rearranging,
in the manner described, the warp ends of any continuous twill
that repeats on an odd number of threads, and in which warp



TWILL AND KINDRED WEAVES.



51



floats are one thread only longer than weft floats. For weft-
face corkscrews, the base pattern must have weft floating one
thread more than warp; but whichever series of threads are




required on the face, they should be of better quahty and in
greater abundance than the mother series.

Fig. 95 shows the method of constructing a warp-face cork-
screw weave B, by rearranging warp ends of the seven-end (^i)



52



GRAMMAE OF TEXTILE DESIGN.



continuous twill weave A, in the manner indicated. It will be
seen that B is produced by rearranging consecutive warp ends




Fig. 97. Fig. 98.

in A at intervals of two threads, or alternately, on the same




Fig. 99.



Fig. 100.



number of warp ends. In like manner, a weft-face corkscrew B




Fig. 101.
(Fig. 96) is produced by rearranging picks of the seven-end ,(^-^)
continuous twill A. Figs, 97 to 101 are examples of perfect
warp-face corkscrew weaves, and Figs, 102 to 106, of weft-face



TWILL AND KINDRED WEAVES.



63



corkscrew weaves, repeating on five, seven, nine, eleven, and
thirteen threads respectively. Judging from these weaves as


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