WOOL.
(24.) _Wool-Bearing Animals._--In most dictionaries wool is defined as
the fleece of sheep, as if, in fact they were the only animals which
yield it, than which nothing can be more erroneous; since we are
assured by the ablest naturalists, that almost every animal, from the
butterfly up to man, possesses more or less of this covering, and that
some indeed rival the sheep in the quantity they bear.
Though wool is possessed in considerable quantity by carnivorous
animals, especially bears, yet the herbivorous quadrupeds, never to
mention the sheep, are principally noticed for its growth, and for
affording a commodity which becomes an article of profit in the hands
of some tribes. Heriot, in his travels through Canada, remarks, that
"the savage women manufacture thread of the wool of the buffalo, and
weave it into cloth. Most parts of the body are invested with a dusky
wool, which is of a quality extremely fine--is much valued--and can
with great facility be used in manufactures. The quantity usually
contained on one skin is about eight pounds."
So far from the sheep being invariably a wool-bearing creature, it
would appear as liable to be entirely destitute of it as some other
animals; for in Tartary, the eastern parts of India, China, and some
parts of Africa, a hair of varying quality forms their sole covering;
and Sir Joseph Banks imported three from Spain, which were smooth,
sleek, and as short-haired as a horse.
(25.) _Structure of the Skin._--The skin is composed of three coats,
or layers; the outermost, the cuticle or scarf-skin, is a thin
delicate membrane, devoid of feeling, and of a scaly texture, pierced
by innumerable small holes, for the passage of the hairs, and
perspiration, and covering the next, or mucous coat, so named from its
pulpy appearance. In this resides the colouring matter, which imparts
its peculiar tints to the hair, and which can only be satisfactorily
demonstrated in the dark races. The existence of this coat has been by
some denied; but it is probable that, though present in all, it can
only be exhibited in such as have depth of tint, to admit of the
display. It is here that sensation principally resides; the nerves, or
rather their terminations, ramifying minutely in its substance, at
which they have arrived by piercing the third tunic, or true skin, a
dense firm elastic membrane, in which the roots of the hairs are
imbedded, and from which, in fact, they take their origin.
(26.) _Sebaceous Follicles._--The skin is studded over by small
glands, or what, in anatomical language, would be called sebaceous
follicles, which vary in number in different breeds, and different
parts of the body, being most numerous on the breast and shoulders,
and secreting a peculiar unctuous semi-solid matter, which, as we
shall immediately see, possesses alkaline properties.
(27.) _Connection of the hair with the skin_--_Yolk._--A hair
implanted in the skin may be compared to a plant growing in a
flower-pot which has been sunk in the earth, as the root of the hair
does not rise directly from the true skin, but from a little cup
extending from it to the cuticle, and receiving nourishment from
surrounding vessels. After coming to the surface of these tunics it
has, in the sheep, yet another, and, in some respects, remarkable
covering to pierce, one which has occupied the attention of the most
distinguished chemists, and given rise to a good deal of disputation
on the subject of salving--we allude to the Yolk. It is supposed by
many to be the inspissated secretion of the sebaceous follicles, and
receives its name from its adhesiveness and colour. It is most
plentiful on fine-woolled sheep, those of the south possessing more
than those of the north of our island, while merinos possess most of
all; so that there is apparently some connection between a fine
fleece, and a good supply of this matter. According to the analysis of
M. Vauquelin, it consists principally of a soapy matter, with a basis
of potash; a small quantity of carbonate of potash; a minute quantity
of acetate of potash; lime in an unknown state of combination; and an
atom of muriate of potash. It owes its odour to a small quantity of
animal oil, and is in every respect a true soap, which would permit
the sheep to be completely washed in a stream, but for the existence
in the fleece of an uncombined fatty matter, which remains attached to
the wool, and renders it rather glutinous.
Many have tried to account for the uses of the Yolk, but nothing like
satisfactory conclusions have been come to: some considering it goes
to form the filament, and is consolidated into a transparent mass
while the pile is growing; while others argue, that it is a peculiar
secretion which exudes through the skin, and by mixing with the pile
renders it soft and pliable, affecting it in the way that oil does a
piece of leather. In the latter opinion I coincide. For my part, I
view it as a secretion, depending very much on good food and
steadiness of temperature, and, therefore, indicative of a fine fleece
only so far as the health of the animal is concerned. In the human
being the state of the skin may often guide us, though blind-fold, to
the quality of the hair, so that the latter may be pronounced either
dry and coarse, or glossy, soft, and silky, as the skin may prove
either harsh and ungrateful, or pleasant, and, if I may be allowed the
expression, alkaline to the touch. Every thing having a tendency to
affect the health may always be considered as calculated to diminish
this secretion, and, consequently, to deteriorate the quality of the
wool.
The relative positions of the layers of the skin, the mode in which
the hairs rise from them, and the form and situation of the sebaceous
follicles, will be better understood by referring to the following
cross section Fig 5. Pl. V., in which the line marked
_a_ Represents the cuticle,
_b_ The mucous layer,
_c_ The true skin,
_d_ Sebaceous follicles,
_e_ Hairs rising from the true skin and inflections of the
upper layers and piercing,
_f_ The thin film of the yolk.
(28.) _Periodical decidence of Wool._--It is affirmed that the only
real difference between hair and wool is in the latter falling off
periodically; but the same change takes place in animals totally
covered with hair; in fact, almost every animal is subject to
moulting, or a periodical decidence of its protecting covering. The
fleece of the sheep has been proved in many instances not to be liable
to _annual_ changes of this description;--Lord Western having, among
others, shown that the wool of the merino may be retained at least
three years without the slightest disposition to separate.
The annual employment of shearing, to anticipate this falling off of
the wool, is now common in most parts of the world; yet some, as the
Icelanders and Kamtschadales, still retain the primeval custom of
_rowing_, or pulling off the fleece in a mass, about the end of May,
at which time it is nearly loosened. This loosening of the attachments
of the fibre is supposed to be owing to a diminution, during winter,
of the nutritive process at the root of the hair, so that the fibre is
liable to give way at the tender part when the fleece becomes heavy
during Spring. This attempt at an explanation meets, however, with the
insurmountable objection, that long-woolled are less liable than
short-woolled sheep to this occurrence, a circumstance which ought to
be the reverse, if weight had any thing to do in the case.
(29.) _Falling off of Wool prevented by Clipping._--Clipping has a
curious influence over the duration of the covering of animals, as is
well exemplified by the correct popular idea, that the only way to
prevent the hair of children dropping off (as it sometimes has a
tendency to do) is to cut it short: we may suppose the benefit in this
case to result from the removal of a _portion_ of each hair, which, if
allowed to remain, would lead to a sacrifice of the _whole_, by
robbing the root of a quantity of nutritious matter, which, owing to a
diminution of reproductive power, it could ill afford. In this way
only can we account for the power which shearing evinces, in putting a
stop to the attempt sometimes made by nature to change the coverings
of some sheep. In the valley which separates the most eastern chain of
the Cordilleras from the central, the wool grows upon the lambs in the
same manner as in temperate climates, provided they are sheared so
soon as it has arrived at a certain thickness; in which case the wool
grows again, preserving the same order. But, if the period for
denuding the animal be allowed to pass, the wool detaches itself in
flakes, leaving behind a short, glossy, and compact hair, exactly
resembling that of the common goat in the same climate.
(30.) _Form of woolly fibre._--The fibre of wool is circular,
differing in diameter in the various breeds, and different parts
of the same fleece. The following _a propos_ observations are
from the article on the Sheep, in the Library of Useful Knowledge:
"The filaments of white wool, when cleansed from grease, are
semitransparent; their surface in some places is beautifully polished,
in others curiously encrusted, and they reflect the rays of light in a
very pleasing manner. When viewed by the aid of a powerful achromatic
microscope, the central part of the fibre has a singularly glittering
appearance. Very irregularly placed minuter filaments are sometimes
seen branching from the main trunk, like boughs from the principal
stem. This exterior polish varies much in different wools, and in
wools from the same breed of sheep at different times. When the animal
is in good condition, and the fleece healthy, the appearance of the
fibre is really brilliant; but, when the sheep has been half starved,
the wool seems to have sympathized with the state of the constitution,
and either a wan pale light, or sometimes scarcely any, is reflected."
The more transparent the filament the better is the fleece, and its
value is impaired by the transparency being different in the same
fleece, or, as often happens, in the same filament; while that which
possesses fineness with a close ground, pureness, elasticity, colour,
tenacity, and not much pitch-mark, is the most esteemed, and preferred
by the manufacturer. Wethers have considerably more wool than ewes. In
every fleece there are several qualities, even so many as nine
different sorts, which are all separated from each other in England by
men called woolstaplers, who are appointed for the purpose, and sworn
to do justice between the grower, and the merchant or manufacturer. In
this manner the latter obtains, without trouble or risk, the very kind
which he knows will suit his purpose; for though the sorter,
surrounded by a number of baskets, divides the wool according to its
properties without the slightest hesitation, and with a rapidity truly
surprising, yet such is the amount of the dexterity acquired by
practice, that a mistake seldom occurs, and his judgment can as rarely
be disputed.
(31.) _Structure and properties of Hair and Wool._--Each hair is
composed of a number of filaments, or smaller hairs, ranged side by
side, and this we can perceive without the slightest trouble, from the
tendency it sometimes has to unravel at the apex; and again, by
drawing a hair through the fingers from point to root, when we feel a
roughness occasioned by projecting filaments, which only proceed a
certain distance up the trunk, the longest being most internal.
Pl. V. Fig. 5, _e_, exhibits those points in a hair considerably
magnified.
These projections, or serrations, which vary in number in different
specimens of wool, are what it depends on for its felting properties.
They are sharper and more numerous in felting wools than in others,
and the better the felting properties of the wool, the more numerous
the curls; because what induces curling on the animal's back leads
to felting in the hands of the manufacturer. In felting, these
projections catch one upon another, and occasion the hair to move in
one direction, which is invariably root foremost, as we perceive on
giving it a twirling motion between the finger and thumb; and it is
only by the union of curve and serration, that felting can be
accomplished certainly and perfectly.
Woolly fibre consists of a semitransparent stem, or stalk, supposed
to be hollow, as represented at Fig. 4, Pl. V. and is partly
distinguished from hair by the latter being opaque. Next to soundness,
there are few qualities deserving of so much attention as softness,
of which the ancient writers make frequent mention, and for the
prevalence of which in our present wools fashion has done not a
little. It is a quality that tends, in a material degree, to the cheap
and easy working of the cloth, and, as such, is said to render wool 25
per cent. more valuable to the manufacturer than a harsh and brittle
pile. It apparently depends on the fineness of the fibre, which should
not, however, go the length of weakness. Fineness is in turn mainly
connected with the yolk, the secretion of which ought, on that
account, to be promoted by attention to the general management of the
animal, as it is well known to undergo a change of properties by
starvation, exposure, or any neglect whatever.
(32.) _Particular soils injurious to Wool._--Soil, also, has much
influence on the pliability of wool. Chalky lands, which are so
notorious for injuring the fleece, are supposed to act in the manner
of a corrosive, but the correct explanation is, not that the chalky
particles attack the fibre in a direct way, but that they render it
brittle, by absorbing the oily moisture with which it is naturally
imbued. Moreover, the plants growing in such situations cannot but be
injurious to sheep, owing to their impregnation, though a slight one,
with calcareous matter; for grooms know well how soon a horse's coat
becomes disordered by the frequent use of hard or well water, and
prefer, therefore, the river for their steeds.[4]
[4] I am surprized to find it asserted at page 76 of the book
on Sheep, published by the Society for the diffusion of Useful
Knowledge, that the depilatory action of lime-water on raw
hides is a "_striking elucidation_" of the injurious effects
of chalk on wool. Lime removes hair from a skin because it is
a powerful caustic, and, as such, speedily decomposes the
animal matter, but the carbonate of lime (chalk) is perfectly
innocuous to wool, except so far as it combines with its oil;
and is as little _corrosive_ to the fleece, as pipe-clay to a
soldier's coat.
(33.) _Felting._--The felting of wool may be defined as a property
depending on the curls and serrations of the fibre, by which it is
allowed to move only with the root foremost, and by which it is
enabled to catch and retain a hold on fibres that are near it, so as
to form a web or cloth. Felting is best brought into operation by
alternate pressure and relaxation, which may be produced in a variety
of ways: the ancient method, and one still pursued by the Tartars, was
to tramp on a mass or layer of moist unwrought wool, so as to form a
coarse cloth or carpet; while the modern, and more perfect plan is,
either, as in hat making, to apply pressure with the hands, or, as in
the finishing of cloth, to pass the fabric repeatedly through rollers.
The way in which a close fabric is formed, by the juxta-position of a
few scattered hairs, gave rise for long, as well it might, to serious
disputations among philosophers; and the favourite theories of each,
unbased as they were on observation, might till now have agitated the
scientific portion of our manufacturers, had not the microscope
brought to light much of what is true and valuable in our researches.
Moisture appears to be of service during the felting of wool, as it
induces it to curl, enabling the fibres to expand, and catch one on
another, after they have been bent and compressed, by the force
applied to them, and is of itself sufficient to felt a fabric, as we
frequently perceive in the instance of stockings, which have been
allowed to remain too long in water, when they become short from
undergoing contraction, and resemble after such treatment an imperfect
cloth. It is for this reason that the hatter, after tumbling over, in
all directions, the fur of which the hat is to be made, wets it before
applying pressure; and, that the woollen manufacturer, after freeing
the web from grease, soaps it before its subjection to the action of
the rollers.
Without felting, cloth would resemble a net, and would unravel on
being cut, from the fibres crossing only in two directions; but the
strokes of the mill put an end to this, by laying the fibres in every
possible direction, and so twining them one with another, as to render
them a coherent mass.
(34.) _Different kinds of Wool._--The wool of this country is divided
into two great classes--long and short: the former varies in length
from three to eight inches, and before being made into stuffs and
worsted goods, requires to be deprived of its felting tendencies, by
passing it through heated iron combs, which remove the feathery parts,
or serrations, and make it resemble silk or cotton.
The shorter combing wools are in general used for hose, and are softer
than the long combing wools. Short wool is employed in the cloth
manufacture, and is, on that account, frequently called clothing wool.
It should approach in colour as much as possible to white, as a clear
white ground is required for all cloths that are to be dyed bright
colours, as well as for those dressed white: grey or black hairs
injure the fleece very much, even though few and minute, as they give
rise to reddish spots where the cloth is stoved. Herefordshire sheep
are entirely free from this defect, and are, therefore, reckoned
particularly valuable for clothing purposes.
(35.) _Alterations induced by Crossing._--The breed exercises
considerable influence on the wool, some sheep, as the merinos, being
distinguished for the softness and beauty of the fleece; while others,
as some of our small northern varieties, are famed for the very
opposite characteristics.
According to the opinion on the continent, any race of ewes, however
coarse and long in the fleece, will, on the fourth cross of the merino
ram, give progeny with short wool equal to the Spanish. The truth of
this proposition is however doubted, in a communication to the Board
of Agriculture, by Dr Parry of Bath; but it is certain, he adds, that
one cross more will in most cases effect the desired purpose. "If we
suppose," he says, "the result of the admixture of the blood of the
merino ram to be always in an exact arithmetical proportion, and state
the native blood in the ewe as 64, then the first cross would give
32/64 of the merino, the second 48/64, the third 56/64, the fourth
60/64, the fifth 62/64, and so on. In other words, the first cross
would leave 32 parts in 64, or half of the English quality; the second
16 parts, or one-fourth; the third 8 parts, or one-eighth; the fourth
four parts, or one-sixteenth; the fifth 2 parts or one-thirty-second;
the sixth 1 part, or one-sixty-fourth; and so on. Now, if the filament
of the Wiltshire, or any other coarse wool, be in diameter double that
of the Ryeland, it is obvious that, according to the above statement,
it would require exactly one cross more to bring the hybrid wool of
the former to the same fineness as that of the latter. This, I
believe, very exactly corresponds with the fact. The difference
between one-eighth and one-sixteenth is very considerable, and must
certainly be easily perceived, both by a good microscope, and in the
cloth which is manufactured from such wool. In the latter method, it
certainly has been perceived; but I have had hitherto no opportunity
of trying the difference by the former. The fifth cross, as I have
before observed, brings the merino-Wilts wool to the same standard as
the merino-Ryeland."
(36.) _Bratting injurious to Wool._--Wool rendered fine by clothing
sheep, is never equal to that which owes its perfection to natural
causes. The Saxon wool, which is principally produced by _artificial_
means, has been compared, from its inelastic sickly appearance, to
grass that has been secluded from the sun. The custom of _bratting_ is
therefore not to be recommended, and indeed is now nearly laid aside.
Housing sheep with the same intentions is also bad, inasmuch as it
must affect their health, and destroy the curl of the fibre. Shelter
is however absolutely necessary from extremes both of heat and cold,
as temperature has much influence on the covering of animals, and in
none more than the sheep.