Francis Lieber.

Library of universal knowledge. A reprint of the last (1880) Edinburgh and London edition of Chambers' encyclopaedia, with copious additions by American editors (Volume 13) online

. (page 166 of 203)
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evidence to prove that there are special conductors in the spinal cord for the
sensations of touch, pain, temperature, and muscular contraction, none of which
can convey other sensations than their own. Notwithstanding its singular power



h-t H Spin azzola.

< A Spine.

of conducting sensory impressions, the gray substance is itself insensible. Among his
other remarkable discoveries in connection with this subject, Browu-Sequard has found,
that on dividing one-half of the spinal cord of an animal, not only is anaesthesia (or loss
of sensation) established on the opposite side of the body, but there is also produced a
state of hyperffisthcshv (or exalted sensibility) on the same side, which begins to appear a
few hours after the operation, and continues in dogs for about 20 days, iii cats about 14
days, and in guinea-pigs for many months, after which the sensibility falls below its
usual standard. With regard to the conduction of motor impulses, there is great uncer-
tainty. Considerable differences have been shown to exist in the position of the motor
tracts in different parts of the cord, and Brown-Sequard concludes from hisexperimen 9
on the effects of section, that while in the dorsal region, all parts, except the posterior
columns, are employed in the conveyance of the orders of the will to the muscles, in the
upper part of the cervical region, most of these conductors are in the lateral columns
and in the gray substance between these and the anterior column.

We have now to consider the spinal cord as an independent nervous center. The sim-
plest, and, at the same time, the most decisive evidence of the independent power of the
spinal cord, is derived from the motion exhibited by the limbs of animals when irrita-
tion is applied to them after section of the cord at some point above the entrance of their
nerves; the fact that these movements are reflected through the cord, and do not result
from direct stimulation of the part irritated, being shown by their complete cessation
when the nerve-trunks are divided. Thus, if a frog be pithed by dividing the cord
between the occipital foramen and the first vertebra, an unusual convulsion takes place
while the knife passes through the nervous center; but this quickly subsides, and if the
animal be placed on the table it will resume its ordinary position. It is quite unable to
move by any voluntary effort; but if a toe be pinched, the limb is instantly drawn up,
and seen to push away the irritating agent, and then draw up the leg again to the old
position.

From these and other experiments, we may conclude (1) that the spinal cord in union
with the brain, is the instrument of sensation and voluntary motion to the trunk and
extremities; and (2) that the spinal cord may be the medium for the excitation of move-
ments, independently of volition or sensation, either by direct irritation of its substance.
or by the influence of a stimulus conveyed to it from some surface of the trunk or
extremities by its nerves distributed upon that surface. For further information on this
subject, the reader is referred to Todd and Bowman's Physiological Anatomy and PJiyxi-
ology of Man, 2d ed., vol. i. ; Carpenter's Human Physiology, 8th ed. 1876; and the othtf
standard works on physiology.

SPINAZZOLA, a city of southern Italy, in the province of Bari, 7 m. s. of Minervino.
Pop. 10,000. The country around is very fertile, and produces grain in abundance.

SPINDLE TREE, Enonymus, a genus of plants of the natural order celasfracew. This
order contains about 260 known species, all small trees or shrubs. The genus enonymn\
has a lobed capsule, and seeds surrounded by an aril, which in some of the species is
remarkable for its brilliancy of color. The common spindle tree (E. Enropceu*), a native
of Britain, chiefly of the southern parts, and of great part of Europe, is very ornamental
when in fruit, and its aril is of a fine orange color. It is a shrub rather than a tree.
The wood is hard and fine-grained. It is used for the liner articles of turnery, and for
skewers. It was formerly used for making musical instruments and for spindles, whence
the name of the shrub. In Germany, the shoots are bored for tubes of tobacco-pipes.
Charcoal made of it is much valued for crayons.

SPINE, or THORN, in botany, is a sharp-pointed projection of the wood of a stem or
branch, and essentially differs from a prickle (q.v.) in being connected with the wood,
and covered with bark. A spine is, in fact, a branch arrested in its growth and modi-
fie^i. In some trees and shrubs, as in the sloe, branches which bear leaves often termin-
ati in the form of a spine. Cultivation, or whatever tends to increase the luxuriance of
a plant, diminishes the tendency to produce spines. The name spine is also given to the
sharp extremities of the midrib of leaves, and to the sharp angular projection of the
margin of hard leaves, as in the holly. In some plants, the stipules are metamorphosed
into spines.

SPINE, CURVATURE OF THE. There are two perfectly distinct forms of curvature,
viz., LATERAL, CURVATURE arising from weakness of the bones, ligaments, and mus-
cles, and fearfully common in girls of the middle and upper classes, between the ages
of 10 and 16 and ANGULAR CURVATURE (frequently known as POTT'S CURVATURE, or
the MALADY OF POTT, in consequence of that eminent surgeon having been the first to
describe its true nature), which consists of caries of the bodies of the vertebrae, and is
by far the more serious affection of the two.

"Lateral Curvature, or Distortion, denotes deformity of the bones of the spine and
chest; with corresponding change of the structure in relation to them. It is called
'lateral,' from the spine being curved sideways; and to distinguish it from 'angular'
deformity, in which the spine is directed from behind forward, owing to excavations in
its forepart' from caries." The above definition is taken from Mr. Shaw's article on this
affection in Holmes's System of Surgery, vol. iv. p. 844, an article from which we have



Spinel. f I Q

Spinning.

borrowed freely in relation to the symptoms and causes of the disease. The first thing
that commonly attracts attention is a projection of one scapula, or an elevation of one
shoulder, generally the right; the right shoulder and right side of the chest being un-
naturally high and rounded, "while on the left side, the shoulder is depressed, and the
side of the chest concave. On examination, the spine is found to have acquired a spiral
appearance, " not unlike what might have been produced if it had been taken, when
soft, at both ends by the two hands, and twisted as a washerwoman wrings a wet cloth."
Shaw, op. cit. In advanced stages of the distortion, the dorsal curve increases abruptly
to such an extent as to render it angular, the attending contortion being similarly abrupt.
This condition gives rise to various changes, including a humped appearance, a great
displacement of the ribs, a diminution of the cavity of the chest, and a proportionate
wasting of the lung. In consequence of these physical changes, the patient can no
longer walk in a simple and natural manner, but exhibits a halting, jerking, awkward
gait.

The following may be noticed amongst the principal causes of lateral curvature: 1.
The suppleness of the spine in the young, its structures being then more gristle than the
bone, and the column virtually immature. 2. Weakness of the muscles, which are seldom
properly exercised in girls of the age and class in which this disorder occurs. This
muscular debility is usually followed by deterioration of the bones and their ligaments,
and this, apart from other obvious and direct bad effects, tends to make all the compon-
ent parts of the spine vertebrae and articulations more prone to yield to the superin-
cumbent weight, and to become distorted. These evil results are increased by prolonged
stooping. When we enter a school, shortly before the breaking up of the class, we
usually find most of the pupils standing or sitting in a tired lounging position. They
are instinctively relieving the pain of over-fatigue by throwing the weight on the insen-
sible fibrous structures, and thus relieving the aclvng muscles. When such attitudes
are long indulged in, the ligaments undergo a process of over-stretching, and a general
looseness of the vertebral joints is the result. By standing on one leg, or, more correctly
speaking, by throwing all the weight of the body on one foot, the body is kept upright
with the least possible expenditure of muscular power. Hence, a weak and fragile girl
is induced to adopt this position. Too long indulgence in this habit will, to a certainty
(for anatomical reasons, into which we have not space to enter), aggravate existing cur-
vature, and induce it, if it did not pre-exist.

However slight a curve in the spice of a young girl may be, it ought to be deemed
of importance; for when the column inclines laterally even to a slight degree, the super-
incumberent weight ceases to be supported on the line of the vertical axis, and falls on
the oblique processes of tlie side to which she leans; and these processes becoming
rapidly diminished in length by absorption, induced by this abnormal pressure, general
distortion rapidly commences. With regard to the final issue of a case, distortion be-
ginning at the age of 10 is more dangerous than at 14, because the disease runs a more
rapid course in the younger cases. A cure is, for the same reason, more easily affected
in the younger patient. If the patient's age be beyond 16, little can be done beyond
Checking the further progress of the deformity.

Before discussing thc'treatment of these cases, it is necessary to say a word regard-
ing an important preventive measure. When a girl is dcfective'in muscular power, dis-
inclined to take exercise, and prone to distortion of the spine, the sitting position does
not afford her rest, in consequence of the great efforts she has to make in order to keep
the body erect. A patient in that condition will derive benefit from being obliged to lie
for two or three hours daily, at divided intervals, on a sofa or board. When the deform-
ity has actually occurred, gymnastic exercises suggested by the medical attendant will
not unfrequently, when continued for some time, have the effect of loosening the con-
nection of the bones, of facilitating their falling into their proper places, when exteu-
tion is employed, and of restoring to the spine a portion of its lost suppleness. Mr.
Shaw suggests the following simple plan for attaining the same end: " Let the patient
lie on one side, with a firm cylindrical pillow, 6 in. in diameter, placed under the
gibbosity of that side, and let her rest her weight on the pillow: the effect will be to
counteract and reverse the curve. The same may be done alternately on the two sides.
The posture may be continued each way for a quarter of an hour at a time, and be
repeated twice or thrice daily." Op. cit., p. 858. There are two methods of extending
the curved spine, viz. (1), by stretching the body while the patient is recumbent; ana
(2) by letting the patient remain upright, and using spinal supports. As each method
has its own advantages, a combination of them will often afford the best results. The
chief objections to the former are the necessary confinement, comparative seclusion, and
interference with the routine of study. Any mode of treatment with the view of pro-
ducing extension of the spine must be continued for months in order to be of any avail.
It would be altogether out of place to notice in this article the various extending beds,
apparatuses for exercise, and different kinds of spinal supports that have been devised
by surgeons and anatomical mechanicians, and we will merely observe that mechani-
cal supports must be tried with great caution. They are always more or less irksome to
bear, and if they are not doing good, are almost sure to be doing harm. On this sub-
ject, the reader may consult Heather Bigg's work entitled The Spine and Upper Extrem-
ities.



JT1 Q Spinel.

Spinning.

Angular curvature consists, as already mentioned, of caries of certain vertebrae,
which first consumes the bones and flbro-cartilages, and subsequently excites a discharge
of pus. The first symptom of this affection is the appearance, at the seat of the caries, of
a prominence of one or more of the spiuous processes. This " growing out" of the back,
as patients frequently term it, is due to the destruction of a portion of the column. In an
advanced stage the spinal ridge will stand out prominently, the knob of each process
being distinctly visible; and finally, a distinct angular projection is developed. The
consequences of this disease are 1hus summed up by Druitt: "1. In favorable cases the
diseased bones collapse, and are ancliylozed; abscesses, if they form, are healed, or their
matter is absorbed, and the patient recovers in two or three years, with more or less
deformity, which is, of course, incurable. 2. In seme fatal cases the patient dies
suddenly from two or three of the diseased vertebrae giving way, and crushing the spinal
cord; or from dislocation of the odontoid process, owing to ulceration of its ligament;
or from the bursting of abscesses into the spinal cord; or from their bursting into the
pleura or peritoneum ; but more frequently death is caused by slow irritation and exhaus-
tion, consequent on the formation of psoas or lumbar abscesses." Tfte Surgeon's Vade-
mecum, 8th eil. p. 348. The most essential point in relation to treatment is rest, and the
.most effectual method of arresting motion between the diseased vertebrae, and of keeping
them at rest is by placing the patient in a recumbent position on his back. If possible,
an invalid bed should be procured, provided with contrivances for enabling him to lie
upon it, day and night, without rising. Local counter-irritants, such as compound
tincture of Iodine, are often useful; and good diet, backed, if necessary, by cud-liver
oil and tonics, must be prescribed. In conclusion, sufferers from any form of real or
suspected spinal disease are earnestly warned to avoid the numerous quacks, whether
in or out of the medical profession, who have taken up the spine as a specialty.

SPI'NEL, a mineral allied to corundum, consisting chiefly of alumina, with smaller
proportions of magnesia, silica, and protoxide of iron. It occurs in crystals, which are
often octahedral, and is chiefly found in Ceylon and Siam. Its colors are various; red,
blue, green, and black. It is much prized as a gem; red spinels are commonly called
rubies; the balas ruby\$ a rose-red spinel, and a violet-colored spinel is known asalamcin-
dine ruby.

SPIN'ET (Ital. fpinnetta), an old-fashioned stringed musical instrument with a key-
board, smaller and weaker than the harpsichord, and, like it, one of the precursors of the
piano-forte. Each note had but one string, which was struck by a quill jack acted on
by one of the linger keys. The strings were placed horizontally and nearly at right
angles to the keys, as in the square pianoforte; and the general outline of the instru-
ment nearly resembled that of a harp laid in a horizontal position, with the keys occu-
pying the position of the sounding-board; on which account the spinet, when first intro-
duced, was called the couched harp.

SPINK, a co. in s.e. Dakota, drained by the Dakota river; 1028 sq.m. ; pop. '80, with
8 other counties, 481 398 of American birth, 4 colored. The surface is uneven, and
the soil is fertile, furnishing good pasturage.

SPINNER, FRANCIS ELIAS; b. N. Y., 1802; learned several trades, and was after-
wards a merchant. He was auditor and deputy naval officer of the port of New York,
1845-49, a democratic member of congress, 1855-57, and afterward a republican member
and chairman of the committee on accounts. He was treasurer of the United States,
1861-75. In the latter year he was an unsuccessful republican candidate for comptroller
of New York state. His services as treasurer were of great value.

SPINNING is the art of combining animal and vegetable fibers into continuous threads
fit for the processes of weaving, sewing, or rope-making. The most primitive spinning
apparatus is the spindle and distaff, representations of which are to be seen on the earl-
iest Egyptian monuments. The distaff was a stick or staff upon which a bundle of the
prepared material was loosely bound, and which was held in the left hand or stuck in
the belt; the spindle was a smaller tapering piece to which the thread was attached. By
a dexterous twirl of the hand the spindle was made to spin round and at the same time
recede from the spinster, who drew out betvveen the forefinger and thumb of the right
hand a regular stream of fibers so long as the twisting of the spindle lasted. It was then
drawn in, the new length of thread wound upon it, and the operation was renewed. An
obvious improvement on this was to set the spindle in a frame and make it revolve by a
band passing over a wheel driven either by occasional impetus from the hand or by a
treadle; this constituted the sjnnning-wheel, which is said to have been invented in
Nuremberg as recently as 1530. In the spinning-wheel in its most improved form, and
as usual for (lax, a bobbin or " pirn," with a separate motion, was placed on the spindle
which had a bent arm a flyer or flight for winding the yarn on the bobbin. The
spindle and bobbin revolved at different rates, the revolutions of the spindle 'giving the
twist, and the difference of the rate' causing the winding on. The two-handed wheel
had two spindles and pirns a little apart, with the distaff or " rock" stuck into the frame
between them, and the spinster produced a thread with each hand. The spinning of
flax on such wheels for the manufacturer was an important branch of domestic industry
ia the northern counties of Scotland as late as 1830, if not later.



Spinola.



720



Neither the spinning-wheel nor the hand could spin more than one, or at most two
threads at a time, and therefore, with the rapid increase of population, and the improve-
ments made in the process of weaving (q.v.), they became quite inadequate to supply the
demand for yarn: but an accident, it is said, about the year 1764, led to an invention by
which eight threads could be spun at once; and this was soon improved upon until 80
could be produced as easily. This was the invention of the spinning-jenny for cotton-
spinning, by James Hargreaves, at Stankhill, near Blackburn in Lancashire. In this
machine, a number of large reels of cotton formed into a thickish coil, called a roving,
were set on upright fixed spindles, and the ends of the rovings were passed between two
small movable bars of wood placed horizontally and under the control of the spinner,
.who could thus make them press, more or less on the roving, and consequently increase
or decrease the draw upon it from the spinning spindles, which were set in a row at the
other end of the frame, and all capable of being set in motion simultaneously by the
wheel The success of the spinning-jenny was considerable, but its history has been too
often told to be required here; and even previous to its invention, a better idea had been,
started and acted upon by others, and was afterward brought to such perfection, that
the invention of Hargreaves soon passed into obscurity.

In order to understand the operations of spinning as now practiced, and as improved
by the invention alluded to, it is desirable, in this place, to say a few words upon the
preparation of the fibers for the process of spinning. In the first place, it wool or cot-
ton, it has to be "opened;" that is, it must be
relieved from its original knotted and lump con-
dition; this was formerly done by hand, but is
now easily managed by machines called ''wil-
lows or willeys," "blowers" and "openers."
By the first of these, which consists of a drum
covered with small spikes moving in a hollow
cylinder, also lined with spikes, but so arranged
that those on the drum pass close to, but do not
come into collision with them as it revolves, the
cotton or wool is fed in on one side, is dragged
forward by catching on the spikes, and is deliv-
ered at an opposite opening to that by which it
entered, in a loose state and free from knots. It
is not, however, quite loose enough for the sub-
sequent operations, and it is more or less min-
t * gled with impurities. It is therefore taken to

the "blower" or "opener," and being put into a shaft, is there acted upon by a stream
of air violently driven in by machinery, which blows it forward, removes extraneous
matters, and so separates the fibers that they pass out at the other end in an exceedingly
light flocculent state, and ready for being formed into laps. This operation consists in
laying the material very equally on an endless apron made of small bars of wood, and
of the width of the frame of the machine in which they are placed. This apron (a, fig. 1)
passes round two rollers, placed at a little distance apart, as in fig. 1. b, c, the rollers
being moved by machinery. The arrows indicate the direction in which the apron
moves; and as the operator covers its entire surface with a thin layer of the fiber, it
passes under under the roller d, and is* taken on to the roller e,. in the form of a com-
pressed layer of cotton or wool, called a lap. When the roller e is full, it is removed,
with its lap/, to make way for another. Much care is taken in weighing out and dis-
tributing the material of these laps, because upon this first operation the ultimate size of
the yarn depends.

The laps are taken to the carding-machine, consisting of a series of cylinders revolv-
ing in a frame, and placed so close together that they almost touch each other. Each
cylinder is covered with a coating of fine steel wire points, which are stuck in leather,
or some other flexible material, and are technically called cards. The production of
these cards by machinery is in itself a marvel, and the automatic machines for making
them are wonderfully effective. Each piece of wire is bent and put through two holes
in the leather so as to form two points on the other side, and these are slightly bent all
in one direction. There are many variations upon this arrangement of the wires, but
the general principle is the same in all. The machine for making the cards cuts the wire
to the right lengths, bends them, pierces the holes in the leather, inserts the wires, and
finishes by giving them the slight sloping direction which is essential.

The lap is made of the same width as the cylinders of the card-machine, and is so
adjusted that, as it unwinds from its roller, it passes in between a pair of the carding
cylinders, the steel wire teeth of which seize hold of the individual fibers, and drag them
in one direction until they are caught by other cylinders, and so carried from one to
another, always being pulled in a straight direction until they are laid as nearly as pos-
sible side by side, and are given off in a thin cobweb-like film at the last cylinder, where
it is prevented from continuing its journey round the cylinders by a small bar of metal
called the doffer, which, with a gentle and peculiar motion, removes it from the cylinder.
The film of fiber is of the same width as the cylinder of the carding-machine, but it is
gathered together by the. operator, who passes it through a smogth metal ring, and




721



Spinola.




FIG. 2.



between two small polished rollers, the revolutions of which carry it forward and
deposit it in n deep tin can in the form of a loose untwisted column of cotton or wool,
about an inch in thickness, which is called a sliver. A small portion of this arrange-
ment is sliosvu. in tig. 2, which represents a carding-machine with only two curded
cylinders, a and b; they are, how-
ever, much more numerous. There
is also a concave rnece of carding, c,
which was formerly much used, but
has lately given way to additional
cylinders, but it makes the action
more apparent in a drawing; d is the
lap drawn on by the action of the
two small rollers e, e, which slightly
press it as they revolve. It is quickly
distributed all over the surface of the
large cylinder a by means of its
numerous wire-teeth ; and as it passes
the roller b, the teeth of which move
in an opposite direction, as indicated
by the arrows, the fibers are caught
off the large, and are carried round the small cylinder until they reach /, where they are
stripped off by the doffer g, and are passed through the ring h, and the rollers i, i, into
the tin receiver k. The sliver is now in the first stage of spinning; it has next to be



Online LibraryFrancis LieberLibrary of universal knowledge. A reprint of the last (1880) Edinburgh and London edition of Chambers' encyclopaedia, with copious additions by American editors (Volume 13) → online text (page 166 of 203)