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and is received in a cylindrical box L, in the centre of of the grains of corn. The thrusting of the arm which a fluted cylinder revolves, which gives the fleeces outwards would naturally tend to thrust forwards a spiral form, the first element of the thread. the ear, but the sharp angles of the grain fixing

The next operation is performed by the slubbing themselves firmly into the shirt-sleeve, maintain the billy. It reduces the cardings by drawing them out in ear in its situation ; if the arm is drawn in, the lengths, joins them in a continuous spongy cord, same cause enables the ear to catch hold of the skin giving them at the same time a slight twist to prevent and to be drawn upwards, and this is repeated every their breaking. The wool is now in the state of a soft time the arm is drawn inwards or forced outwards. thread, similar to a roving in the cotton manufacture, Now the construction of the hair of the sheep and and is called a slubbing; it is now ready to be spun the ear of corn is somewhat similar, and the mag. into a thread of a harder texture. The operation of nified view of three kinds of wool, fig. 3, will show the slubbing and spinning in worsted so nearly agree with reason why one sort will felt and the other will not. the same processes in the cotton manufacture, that it The long English wool a, it will be seen, is much less would be unnecessary again to enter upon the subject. notched on its surface than the Saxon B, or the original

When the cloth first comes from the weaver, it is Spanish c, and therefore resembles less the ear of in a very rough unsightly state, and contains a corn, and will not be acted on in the same manner. quantity of oil, with which it has become combined The fibres of the cloth made of short wool on being during the several processes it has undergone. The subjected to the operation of fulling, shrink connext operation is scouring, which is performed in the siderably in their length, and close in, as it were, fulling-mill, the cloth being soaked in an alkaline ley, upon each other. The jagged ends of this wool now and beaten by machinery; it is then well rinced with become entangled, and any attempt to stretch the pure water and hung on the tenter-frames to dry. cloth again to its original length and width would be When dry, it is taken down and examined carefully, useless; the more frequently this operation of fulling the knots picked out, and any rents or cuts it may is repeated, the thicker the texture of the cloth behave received, repaired by introducing fresh threads; comes, and it is then said to be double milled. We this is called burling. The cloth has now to be know that if common woollen cloth, when made up into thoroughly cleaned in the fulling-mill, by means of a garment, should get wet, it shrinks considerably, soap and water

much to the annoyance of the wearer, who, in this The next process is milling, or felling. In the state manner, has it milled upon his own person. The in which the cloth is received from the tenter-field, felting of wool in the manufacture of hat bodies, is the naked threads are very perceptible, and the effected by acting on the same principles, but the operation of milling is to swell the threads, and felt process is more frequently repeated, so as to cause the them so as to allow of the cloth afterwards receiving fibres of the wool to be completely matted together. that fine smooth and polished surface, which is the After the milled cloth has been properly dried, it great beauty of fine cloth, and which renders it also has to be dressed; this was formerly done by means more impervious to wet. Commonly, a piece of cloth of the seed-vessels of the fuller's teasle, formed into of sixty-two yards, requires six pounds of soap, which a kind of hand card, but latterly it has been effected is dissolved in water, and about a handful spread by machinery, and in some cases by means of very upon each yard in length; the piece is then put into fine wire cards. The dressing is the process by a trough and worked for three hours in the fulling. which the nap is raised. mill. After twelve hours milling, the cloth is reduced The last operation the cloth has to undergo is in breadth about two-fifths, and in length one-third; called shearing, or cropping ; the wool, by the operation it is now again strained on the tenter-frame, by which of dressing, covers the surface of the cloth like loose it is stretched about one-twentieth, or two yards in fur, which must be removed before it is fit for the forty, but it is very little extended in breadth. The market; this was formerly effected by hand with a property of felting is only possessed by the short large pair of shears, but of late years this part of wool, and it is of so singular a nature, that it deserves the manufacture has also been performed by the aid particular notice.

of machinery. The cutting instruments resemble the If an ear of bearded corn is introduced between blades of the hand shears, one blade is fixed in an the wristband and the wrist, the stalk being placed oblique direction, while a revolving cylinder is furtowards the shoulder, the common motions of the nished with several moving blades, which act in sucarm will cause the ear of corn to move upwards until cession against the fixed blade, in the same manner it reaches the shoulder, and this occurs whether as if a pair of shears were worked by hand. The the arm is thrust out of the sleeve or drawn back; cloth itself is stretched over a metal bed to prevent this motion takes place by means of the jagged ends its lying in creases. The list being thicker than the

rest of the fabric is left unsheared, the blades of the stramonium, and bella donna. The well-known effect cutters not being of a sufficient width to cut the nap which these substances possess of dilating the pupil with which it is covered, and as the list is thicker when applied to the surface of the eye, or of the than any other parts of the cloth, grooves are con- neighbouring parts, differs only in degree from what trived for its reception, and to allow the shears to follows their being taken into the stomach ; but clip close.

instead of effecting a loss of power or paralysis of Some of the common woollen cloths are hot- the iris, they seem rather to act as stimuli on the anpressed to give them a face, and as this smoothness tagonist fibres which compose the greater ring of the should only appear on one side, the other is made iris, and thus overcome its normal or regular obedirough again by means of a sponge and water; this ence to the stimulus of light, analogous to those kind of cloth is also dyed after weaving, and the list involuntary and spasmodic actions which they occais sewn on to give it the appearance of having been sion when taken internally. See Vetch on Diseases dyed ingrain.

of the Eye, Christison also in his Treatise on Poisons, cites numerous interesting cases of the effect of

narcotic poisons on the pupil of the eye, ON EMPLOYMENTS WHICH INJURE THE

EYE-SIGHT. No. IV.

EFFECTS OF THE EXPOSURE OF THE EYE

TO ACRID FUMES.

any of

us,

LAVA. MOUNT VESUVIUS. (4.) We need not offer more than one illustration It was in the month of February (1793) that I went to this class, inasmuch as others will be readily with a party to the source of the lava, for the first suggested to the reader's own mind when we state time, to ascertain the real state in which the lava prothat many fumes, vapours, gases, such as those ceeded from the volcano that created it. I found the afforded by ammonia, muriatic acid, &c., so affect the crater in a very active state, throwing out vollies of sentient apparatus of the eye as to cause a general | immense stones, transparent with vitrification, and irritability which the eye itself tends to remove by such showers of ashes involved in thick sulphurous exciting a flow of tears. This power, however, is clouds, as rendered any approach to it extremely danlost in time ; inflammation comes as a prelude to gerous. We ascended as near as possible, and then, disease of a permanent and more lasting character. crossing over to the lava, attempted to coast it up to

The case we have selected is a remarkable one, its source. This we soon found was impossible, for an illustrating the noxious effects resulting from expo- unfortunate wind blew all the smoke of the lava hot sure of the person to acrid fumes. A class of upon us, attended at the same time with such a thick persons employed in cleansing the immense sewers mist of minute ashes from the crater, and such fumes of the city of Paris are subject to a disease which of sulphur, that we were in danger of being suffocated. is called in one case la mitte, in the other case le In this perplexity I proposed immediately crossing plomb. The former is caused by ammoniacal vapours, the current of liquid lava, to gain the windward side and is announced by a smarting in the eyes, and of it, but felt some fears, owing to the very liquid the eye-ball and pupil soon become red, accompanied appearance the lava there had so near its source, with other pains, chiefly about the head. Blindness

All my companions were against the scheme, and often results, which lasts for a day or two. The while we stood deliberating, immense fragments of patients endure much pain, and get no relief until stone and huge volcanic bombs, that had been cast tears begin to flow. In slight attacks exposure to the out by the crater, but which the smoke had preopen air and shading the eyes is a sufficient remedy: vented us from observing, fell thick about us, and if the attack is strong the men are accustomed to rolled by us with a velocity that would have crushed wash their eyes in cold water, to tie a wet bandage

had we been in their way.

I found we over them, and to remain in the dark.

must either leave our present spot, or expect instant Le plomb is also due to gaseous exhalations, chiefly death : therefore, covering my face with my hat, sulphuretted hydrogen and ammoniacal gases, pro. I rushed upon the lava, and crossed over safely to ducing convulsions and other alarming symptoms. the other side, having my boots only a little burnt, The danger to these workmen is now entirely removed and my hands scorched. Not one of my companions, by the copious use of chlorine in combination with however, would stir ; nor could any persuasion of lime or soda, as chlorine possesses the valuable pro- mine avail in getting a single guide over to me. I perty of entirely destroying and neutralizing these then saw clearly the whole of the scene, and expected effluviæ,

my friends would every moment be sacrificed to It is perhaps in this place that we may mention a their own imprudence and want of courage, as the train of effects resulting from narcotics taken in-stones from the crater fell continually around them, wardly, The effects produced do not certainly come and vast rocks of lava bounded by them with great under the denomination of fumes as ordinarily con force. At last I had the satisfaction of seeing them sidered ; but, be that as it may, the subject is one of retire, leaving me entirely alone. I begged hard for much importance, and we do not wish to pass it over a torch to be thrown over to me, that I might not be unnoticed.

lost when the night should come on. It was then Amaurosis is caused by the use of narcotic sub- that André, one of the cicerones of Resina, afer being stances which have been supposed to act specifically promised a bribe, ran over to me, and brought with in depressing the energy of the nervous system in him a bottle of wine and a torch. We had coasted general. The symptoms of amaurosis, however, the lava ascending for some time, when looking back by no means support the opinion that they have a I perceived my companions endeavoring to cross the direct sedative operation : the loss of sensibility, as lava lower down, where the stream was narrower, well as the dilatation of the pupil, may be the effect In doing this they found themselves insulated, as it of increased excitement, or a full state of the vessels ; were, and surrounded by two different rivers of liquid for besides considerable external turgescence, sensi- fire. They immediately pressed forward, being terbility of the pupil almost invariably returns on ribly scorched by the combined heat of both the curhaving recourse to bleeding. The principal substances rents, and ran to the side where I was ; in doing of this class are opium in large doses, hyosciamus, which one of the guides fell into the middle of the

one

red-hot lava, but met with no other injury than of materials less soluble than the rest of the lava, having his hands and face burnt, and losing at the lighter, and of course liable to float continually on same time a bottle of vin de grave, which was broken the surface. There is, however, no truth in this. by the fall, and which proved a very unpleasant loss All lava at its first exit from its native volcano flows to us, being ready to faint with excessive thirst, out in a liquid state, and all equally in fusion. The fatigue, and heat. Having once more rallied my appearance of the scoriæ is to be attributed only to forces, I proceeded on, and in about half an hour I | the action of the external air, and not to any difgained the chasm through which the lava had opened ference in the materials that compose it, since any itself a passage out of the mountain. To describe lava whatever, separated from its channel, at its very this sight is utterly beyond all human ability. My source, and exposed to the action of the external air, companions shared in the astonishment it produced ; immediately cracks, becomes porous, and alters its and the sensations they felt, in concert with me, form. As we proceeded downwards this became were such as can be obliterated only with our lives. more and more evident, and the same lava which at All I had before seen of volcanic phenomena did not | its original source flowed in perfect solution, undilead me to expect such a spectacle as I then beheld. vided, and free from loose encumbrances of any kind, I had seen the vast rivers of lava that descended into a little farther down had its surface loaded with scoria, the plains below, and carried ruin and devastation in such a manner, that upon its arrival at the bottom with them; but they resembled a vast heap of cin- of the mountain, the whole current resembled nothing ders, or the scoriæ of an iron-foundry, rolling slowly so much as a rolling heap of unconnected cinders along, and falling with a rattling noise over from an iron-foundry. another. Here a vast arched chasm presented itself The fury of the crater continuing to increase, mein the side of the mountain, from which rushed, with naced us with destruction if we remained any longer the velocity of a flood, the clear vivid torrent of lava in its neighbourhood. A large stone, thrown out to a in perfect fusion, and totally unconnected with any prodigious height, hung for some time over our heads other matter that was not in a state of complete solu. in the air. Every one gave himself up for lost, until tion, unattended by any scoriæ upon its surface, or it fell harmless beyond us, shattering itself into a gross materials of an insolvent nature, but flowing thousand fragments, which rolled into the valley with the translucency of honey, in regular channels, below. We had not left this spot above five minutes cut finer than art can imitate, and glowing with all before a shower of stones, issuing from the crater, the splendour of the sun.

fell thick upon it, covering the source of the lava, The eruption from the crater increased with so and all the parts about it ; so that had we waited, much violence that we proceeded to make our expe as I begged to do, a little longer, every one of us riments and observations as speedily as possible. A A would have been crushed to atoms. little above the source of the lava I found a chimney During my second visit the appearances were of about four feet in height, from which proceeded pretty much the same. I though the lava flowed smoke, and sometimes stones. I approached and slower, and was less in fusion than before, the surgathered some pure sulphur, which had formed itself face appearing tougher, and being sooner converted upon the edges of the mouth of this chimney, the into scoria. We dressed our beef-steak upon the lava, smell of which was so powerful, that I was forced to no fire being better calculated for that purpose, hold my breath all the while I remained there. I owing to the excessive heat it gives. seized an opportunity to gain a momentary view Upon my third visit I found the lava had taken a down this aperture, and perceived nothing but the different course, and flowed towards the Torre del glare of the red-hot lava that passed beneath it. We Annonciato, whereas it had before proceeded in a then returned to examine the lava at its source. Sir channel exactly opposite the cross. The source itself W. Hamilton had conceived that no stones thrown had undergone great alterations, and bore strongly upon a current of lava would make any impression. the marks of an earthquake.--Bishop OTTER'S We were soon convinced of the contrary. Light bo- Life of Clarke. dies of five, ten, and fifteen pounds' weight made little or no impression, even at the source ; but bodies of sixty, seventy, and eighty pounds, were

THERE is inconsistency and something of the child's proseen to form a kind of bed upon the surface of the pensities still in mankind. A piece of mechanism, as a

watch, a barometer, or a dial, will fix his attention. A man lava, and float away with it. A stone of three hun- will make journeys to see an engine stamp a coin or turn dred weight, that had been thrown out by the crater, a block; yet the organs through which he has a thousand and laid near the source of the current of lava, I sources of enjoyment, and which are in themselves more raised upon one end, and then let it fall upon the exquisite in design, and more curious both in contrivance liquid lava, when it gradually sunk beneath the sur and in mechanism, do not enter bis thoughts; and if he

If I wished to describe the admire a living action, that admiration will probably be manner in which it acted upon the lava, it was like by what is natural and perfectly adjusted to its office - by

more excited by what is uncommon and monstrous, ihan a loaf of bread thrown into a bowl of very thick honey, the elephant's trunk than by the human hand. This does which gradually involves itself in the heavy liquid not arise from an unwillingness to contemplate the superithat surrounds it, and then slowly sinks to the ority or dignity of our own nature, nor from an incapacity bottom. The lava itself had a glutinous appearance ;

of admiring the adaptation of parts. It is the effect of haand although it resisted the most violent impression, bit. The human hand is so beautifully formed, it has so

fine a sensibility, that sensibility governs its motions so seemed as if it might easily be stirred with a common

correctly, every effort of the will is answered so instantly, as walking-stick. A small distance from its source, if the hand itself were the seat of that will. Its actions are as it flows on, it acquires a darker tiut upon

its sur

so powerful, so free, and yet so delicate, that it seems to face, is less easily acted upon, and, as the stream possess a quality of instinct in itself, and there is no thought gets wider, the surface having lost its state of perfect of its complexity as an instrument, or of the relations solution, grows harder and harder, and cracks into which make it subservient to the mind: we use it as we innumerable fragments of very porous matter, to

draw our breath, unconsciously, and have lost all recol

lection of the feeble and ill-directed efforts of its first exerwhich they give the name of scoria, and the appear

cise by which it has been perfected. Is it not then the ance of which has led many to suppose that it pro very perfection of the instrument which makes us insen ceeded thus from the mountain itself, being composed sible to its use ? ---BELL.

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covers turned back,

THE CICADA, AND ITS ORGANS OF VOICE. in others transparent, and reflects

Fig. 2.
The Cicadæ are insects belonging to the order called all the colours of the rainbow;
Hemiptera, (half-winged,) on account of the wings sound, but is supposed to modulate

this mirror is not the real organ of partaking generally of a double character, being it. The middle portion is occupied partly of a leathery substance and partly transparent; by a plate, of a horny substance, in the Cicadæ, however, this distinction is not so placed horizontally, and forming apparent. The Cicadæ are found in abundance in the bottom of the cavity B. On

D---most of the warmer parts of the globe; there are its inner side this plate terminates also several species, natives of more temperate regions. in a crania, or elevated ridge, comThese insects are noted for the singular noise they plate and the after-breach, (post produce, and on this account they were in great pectus,) another membrane, folded favour among the ancient Greeks. They were kept transversely, fills an oblique, obin cages for the sake of their song, and were a long, or semilunar cavity. In some favourite image of innocence and cheerfulness with species I have seen this membrane the poets of Greece. One bard intreats the shep- stretch or relax it at pleasure, but

in tension, probably the insect can herds to spare the innoxious Tettix, (the Greek name

even all this apparatus is insufficient for the Cicada,) that nightingale of the Nymphs, and to produce the sound of these anito make those mischievous birds, the thrush and mals. One, still more important blackbird, their prey.

and curious, still remains still to be

Under View, with the DrumSweet prophet of the Summer, (says Anacreon, address- described. This organ can only be ing this insect,) the Muses love thee; Phæbus himself discovered by dissection. A portion of the first and second loves thee, and has given thee a shrill song; old age does segments being removed from that side of the back of the not wear thee out; thou art wise, earthborn, musical, im- abdomen which answers to the drums, two bundles of muscles, passive, without blood.

fig. 3, B, meeting each other in an acute angle, attached

to a place opposite to the point of the mucro (a pointed proThe sound produced by the Grecian Cicada must minence, like a sharp tooth,) of the first ventral segment of necessarily have been musical ; it was called by the the abdomen will appear. These bundles consist of a prosame name as the music of the harp.

digious number of muscular fibres, applied to each other, A Cicada, sitting upon a harp, was a usual emblem of but easily separable. Whilst Réaumur was examining one the science of music, which was thus accounted for:-When of these, pulling it from its place with a pin, he let it go two rival musicians, Eunomus and Ariston, were contending again, and immediately, though the animal had been long upon that instrument, a Cicada, flying to the former, and dead, the usual sound was emitted. sitting on his harp, supplied the place of a broken string their sounds, here are parts

enough to do it for them, for the

If these creatures are unable themselves to modulate and so secured him the victory.

mirrors, the membranes, and the central portions with their The Cicadæ of modern times are equally famous

the cavities, all assist in it. If you remove the lateral part for the power, if not for the musical property of their of the first dorsal segment of the abdomen, you will discover voice. Dr. Shaw, in his Travels, says,

Fig. 3

a semi-opaque, and nearly In the hotter months of Summer, especially from mid

semicircular concave-convex day to the middle of the afternoon, the Cicada is perpe

membrane, with transverse tually stunning our ears with its most excessively shrill

folds, fig. 3, A; this is the and ungrateful noise. It is, in this respect, the most

drum. Each bundle of mustroublesome and impertinent of insects, perching upon a

cles before mentioned, is twig, and squalling sometimes two or three hours without

terminated by a tendinous ceasing, thereby too often disturbing the studies or short

plate, nearly circular, from repose, which is frequently indulged in in these hot climates

which issue several little for a few hours.

tendons that, forming a The Brazilian Cicadæ are said to sing so loud, that

thread, pass through an

aperture in the horny piece they can be heard at the distance of a mile. On

that support the drum, and account of the sound this insect produces, it is called

are attached to its under or in the United States, the American Locust.

concave surface. Thus the The apparatus by which the male Cicada produces

bundle of muscles, being the sound for which it is famous, is thus described

alternately and briskly rein Kirby and Spence's beautiful work on Entomology.

laxed and contracted, will If you look at the underside of the body of a male, the

Back View ; several Portions of the

by its play, draw in and let

Skin removed to show the Drum out the drum, so that its first thing that will strike you is

and its Muscles.

convex surface being thus a pair of large plates, of an irre

rendered concave when pulled in, when let out, a sound will gular form, B; in some semi- be produced by the effort to recover its convexity, which B oval, in others triangular, in

sound striking upon the mirror and the other membrane. others again a segment of a cir

before it escapes from under the operculum, will be moducle of greater or less diameter, lated and augmented by them. I should imagine that the covering the anterior part of the

muscular fibres are extended and contracted by the alternate belly; these are the drum-covers, approach and recession of the trunk and the abdomen to or opercula, from beneath which

and from each other.
the sound issues, at the back of
the posterior legs. Just above
each operculum there is a small
pointed triangular process, (per-
sillum,) A, the object of which,

as Réaumur supposes, is to
Under View, with the Drum.
covers in their Places,

prevent them from being too

much elevated. When an operculum is removed, beneath it you will find, on the exterior side, a hollow cavity, with a mouth somewhat linear, (like

The Drum of the Cicada, a slit, the width of a line,) fig. 2, A, which seems to open into

and the Museles by which the interior of the abdomen. Next to this, on the inner

it is moved. side, is another large cavity, B, of an irregular shape, the bottom of which is divided into three portions: of these the

LONDON: posterior is lined obliquely with a beautiful membrane,

JOHN WILLIAM PARKER, WEST STRAND. which is very tense, c; in some species semi-opaque, and

PUBLISHED IN WEEKLY NUMBERS, PRICE ONE PENNY, AND IN MUNTHLY PANTS

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A. Fig. 1.

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THE CICADA.

PRICE SIXPENCE.

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GENERAL FEATURES OF THE WORLD ACCORDING TO THE GEOGRAPHERS JUST BEFORE THE CHRISTIAN ERA.

PART II.

seemed the natural limits of marine excursion. The great CAUSES OF THE ROMANCE OF ANCIENT

antiquity of the Phænicians, however, is perhaps the NAVAL HISTORY.

reason why our knowledge of them is obtained from inci

dental and isolated accounts: but on the naval spirit and We have already observed that the scene of the earliest industry of Carthage, a colony planted by the former power, known navigation was the Mediterranean Sea, which in the ninth century before Christ, the light of history, naturally seemed to the ancients to be situated in the owing to their connexion with the Romans, is more middle of the earth ; as is implied by its name. As navi. abundantly shed. With the Carthaginians, perhaps, had gation advanced only at a creeping pace, and as but a small originated the idea of quitting the Mediterranean by the amount of fresh experience was laid up by one generation straits of Gades, (now Gibraltar,) of sailing southward, for the benefit of the next, it took very many ages to ex circumnavigating the coast of Africa, and then returning plore the Mediterranean, Tyrrhene, Hadriatic, and Ægean northward by the Red Sea, towards the Levant, or eastern seas. The people of Tyre and Sidon, the Phænicians, side of the Mediterranean. This notion seems to have “whose merchants were princes,” (Isaiah xxiii. 8.) were been cherished for ages, as the prime, the crowning enteramong the first wbom the spirit of commerce and the prise, long thought of and debated; but which only a desire of gain had made dissatisfied with what had hitherto solitary few, at long intervals of time determined to try Vol. XII.

379

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