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the opposite state. Before the electricity proceeding or feather will fly towards the conductor, aclhere to it from the machine can reach the ground, it must pass for a moment, then return to the hand, and back from one or both of the outside bells to that in the again to the conductor; and by a little management middle, which is accomplished by the brass clappers on the part of the operator, it may be made to do so suspended between them, being alternately attracted at a distance much greater than that we have menand repelled in the same manner as the pith-balls tioned, and during many minutes in succession. already described; and thus, in conveying away the Suspend by a chain from the conductor a small electricity, the clappers strike the bells and set them metallic bucket containing water, a tube being inringing.
serted in the bottom of the bucket, the bore of which Another experiment equally amusing as any of the is so small that water will pass through it only drop preceding, and affording one of the finest illustrations by drop. On setting the machine in motion the
that can well be imagined of water will flow rapidly through the tube, separating
ductor, and the other at about To these, if we deemed it necessary, we could add four inches below it, supported by a suitable, but not many more illustrations of electrical attraction and an insulated, stand. Place on the lowermost plate, repulsion. We must not, however, omit the following two or three pith figures of men or women, (which extremely simple, yet useful, piece of apparatus, can be obtained at the philosophical instrument which is called Henley's Quadrant Electrometer. makers' very beautifully formed,) and on turning the consists of a stem of wood or metal, about eight machine the figures will start up and execute evolu- inches long, terminating at one end in a tions so rapid and fantastic, that they would be ball, and the other tapered so that it may deemed hardly possible by persons who had not fit tightly into the conductor. To the before witnessed them. In this case we see the force upper part of this stem is attached a of gravity in the figures overcome by the attractive semicircular piece of some hard wood, and repulsive influence of the electricity they are the or, what is much better, of ivory, on means of conveying from the upper to the lower which is a scale of 180 equal parts, plate; a very feeble current of which is sufficient to reckoning ninety from the upper and preserve at least two of the figures in an erect posture, | lower parts of the scale to the point most for any length of time that may be desired. To un- distant from the stem. In the centre of derstand this experiment properly, the room in which the semicircle is a pin, to which is susit is performed should be partially darkened, when pended, so that it may move freely, a each extremity of the figures will be seen to be illu- very slender. rod of box-wood, or cane, say, five minated by the current of electricity which is passing inches long, a pith-ball being attached to its lower through it. If the machine be turned quickly, more extremity. The use of this instrument will be hereelectricity will be excited than the figures can carry after explained; but its action depends on the reoff; and then a portion will be observed making its pulsion existing between the stem, when electrified escape from the edges of the uppermost plate into by contact with the machine, and the moveable rod; the atmosphere. Where pith figures, such as we refer and in proportion as the pith-ball recedes from the to, cannot be had, their places may be supplied by stem, do we judge relatively of the intensity of the paper ones; but the paper of which they are made charge of accumulated electricity. must not be very thick.
It is impossible, within anything like reasonable limits, to give a full description of all the methods Taz character of the true philosopher is to hope all things by which examples are furnished of electrical attrac. not impossible, and to believe all things not unreasonable. tion, and repulsion, as accompanying every case in He who has seen obscurities which appeared impenetrable which the electrical relations of bodies are disturbed. and the most barren and unpromising fields of inquiry
in physical and mathematical science suddenly dispelled, But we shall mention a few more, and we hope to converted, as if by inspiration, into rich and inexhaustible make them intelligible without the aid of figures. springs of knowledge and power, on a simple change of
Fix a short blunt wire into the prime conductor, one point of view, or by merely bringing to bear on them and to the end of it attach a piece of sealing-wax.
some principle which it never occurred before to try, 'will If the wax be for a moment inflamed, and just when surely be the very last to acquiesce in any dispiriting prosit is blown out, the machine set in motion, a great while, on the other hand, the boundless views of intellectual
pects of either the present or future destinies of mankind;. number of long and very slender filaments will be and moral, as well as material relations, which open on bim separated from the mass; and if a sheet of writing on all hands in the course of these pursuits, the knowledge paper be held about a foot from the wax, the filaments of the trivial place he occupies in the scale of creation, and will adhere to the paper in the form of very beautiful the sense continually pressed upon him of his own weaknet work.
ness and incapacity to suspend or modify the slightest Hold in the hand, about six inches distant from him, must effectually convince him, that humility of pre
movement of the vast machinery he sees in action around the conductor, a piece of cotton wool or a very light tension, no less than confidence of hope, is what best bedowny feather. On exciting the machine, the cotton comes his character.-_HERSCHEL,
THE VILLAGE OF LEADHILLS, fectly coincided with Newton's determination, that the
revolving body was not an accurate elliptical spheroid, The village of Leadhills is situated in the parish of but approached infinitely near to that figure. When Crawford, and county of Lanark, Scotland, at the at Leadhills he instituted a library among the miners, altitude of 1280 feet above the level of the sea. The and strongly advised them to subscribe; and with prevailing rock in the neighbourhood is greywacké; such success, that there is not a workman about the but at no great distance clay-slate and green-stone village who is not a member of the library. The are found, and coal within ten miles, at Sanquhar number of volumes, embracing the standard works and Douglas. The altitude of the Lowthers, the on every branch of science, in 1830, amounted to two highest hill in the neighbourhood, is about 2400 thousand, whilst the miners at Wanlockhead, another feet.
mining village within two miles of Leadhills, but in According to common report, the lead mines were the county of Dumfries, possess another library, discovered by a German of the name of Bulmer, when almost equally extensive. The effects of such instisearching for gold in the banks of the adjoining rivu- tutions have been felt, not only in civilizing the inlets. This account is extremely probable; for the habitants generally, but the small village of Leadhilis
, numerous hillocks on the banks of the streams containing twelve hundred inhabitants, has the which discharge themselves into the Clyde and Nith, honour of producing two men, whose names bid fair bear evident indications of having been thoroughly for immortality—Allan Ramsay, the poet, and Wil. searched for that precious metal: even so much so liam Symington, the engineer. that those miners who at present amuse themselves Whilst in other mining districts, crimes are of freduring their leisure hours, in searching for gold, quent occurrence, none, excepting petty offences, were cannot find a soot that has not nreviously been ex- ever committed here; and whilst the children of colplored.
liers and miners are generally entirely illiterate, there The method of searching for gold, is, I believe, the is neither a boy nor a girl in these villages, who cannot same in every country. However, the one adopted read, and most of them can write. To whatever at Leadhills is as follows: the surface of the rock is cause it may be attributed, (and I think it is due to laid bare; the earth, sand, &c., in its crevices, are the taste for reading that has been produced amongst collected, riddled, and washed. The water carries them)—the apparent comfort of the people, the away the earthy particles, and leaves those materials neatness of dress of the children, and the intelligence which are of greater specific gravity than itself, as of the men, cannot be denied. For not only to fint, quartz, and what gold there may be. The pro- miners in other parts of the world are they superior, ceeds from one puddle, as it is called, are generally, but to the working classes even in Scotland, which is at the most, not more than a few particles, not larger admitted to possess the most intelligent peasantry on than the point of a pin; but a man in six hours, at earth, an average, may collect about four pennyworth of Seeing then that such beneficial effects have been gold. Some pieces, however, have been found as produced by such apparently small causes, might not large as a pea, or small bean.
the overseers of other mining districts, instigated by These gold-mines, however, were once productive; the example of Leadhills, try to institute reading socifor history informs us that in the reign of James V. eties among their workmen? for it will always be of Scotland, three-hundred men were employed in found that correctness of moral conduct follows the them ; and when that monarch, in a hunting excur- cultivation and enlightenment of the mind. It is sion in the adjacent moors, dined in Crawford castle, true that the Leadhills and Wanlockhead miners each of his retainers, for dessert after dinner, was possess two special advantages; they only work six presented, on a wooden platter, with a few bonnets hours in the twenty-four, and have the perquisite of crowns, as the produce of the soil. These pieces obtaining as much iand from their landlords, the Earl were coined from gold obtained in the mines of Glen- of Hopetoun at Leadhills, and the Duke of Bucgonar, the rivulet upon which Leadhills is now built. cleuch, at Wanlockhead, as they can cultivate with
Lead, however, for centuries, has formed the the spade. The last might be considered as of mineral riches of these mines. The vein has more hardly any advantage in a pecuniary point of view, than once expanded to the enormous width of four- as the uncultivated land in the neighbourhood rents teen feet; but I myself never saw it more than four at two shillings per acre; but it is still unknown and a half feet, and this was considered by the miners what spade labour can effect, even in the most unproas a very good lead. At present the crip, or annual mising circumstances, as will be proved from an number of bars, (of one hundred and forty-four | account which I have received of the enormous crops pounds each,) amounts to 10,000 in Leadhills, and that have been produced at Leadhills, and which I to about 8000 in Wanlockhead; whereas at one period communicate as being important, not only in an eco35,000 were made at the former, and 15,000 at the nomical, but also in a geological point of view latter.
The account to which I refer appeared in the ScotsIt is not, however, to facts such as I have men
It is as follows:—“Mr. John Hunter, Leadtioned, that I particularly wish to call attention, but hills, planted in 1835 sixteen Scotch falls (being the to the mental superiority of these miners over miners tenth part of a Scotch acre) with potatoes, which proin other parts of the world, and to show that even duced the extraordinary quantity of 335 imperial among a class of workmen who might be supposed stones, being at the rate of twenty-one tons to the incapable of profiting by good example, one man of Scotch acre (or seventeen and a half to the English). intelligence may produce beneficial effects, that for And from a square mile of surface, around the village, ages will be felt and duly appreciated. This indivi- it is calculated that 25,000 stones of hay (twenty-two dual was Mr. James Stirling, who in the middle of pounds to the stone), and 12,000 stones of potatoes, the last century, was overseer at Leadhills. Mr. Stir- are annually produced." The allotment system has ling is kuown to the mathematical world for two been strongly advocated by Mr. Howitt, as being well elegant propositions, which he communicated to the fitted to a considerable extent, and with great advanRoyal Society of London, in 1735, for determining tage, both economically and morally, as confirming the form of a homogeneous spheroid turning round the moral sentiments and social condition of the peois axis; and which, when applied to the earth, per- | ple, in the neighbourhood of Nottingham; but the
climate of Nottingham is, I believe, as fine as any in
THE MEDICINAL LEECH, England; whereas at Leadhills it is quite the reverse :
(Hirudo medicinalis) and still human labour has triumphed over the sterility May be known by having six yellowish lines, or striæ, of the soil and the backwardness of the climate.
on its back, while the under part is of a greyish hue “When further attention,” remarks the editor of spotted with black; but, as we shall presently see, the Scotsman, “is now so generally called to the prac- these markings are not uniformly found. The Mediticability of improving our waste lands, this instance cinal Leech is common throughout the whole of of productiveness at Leadhills, a mountain district
Europe, but is much more abundant in the southern higher than the summit of the Pentland range, near parts; it is generally about three inches in length. Edinburgh, ought certainly to be a strong proof of formerly it was very abundant in Great Britain, but the possibility of employing our pauper population the improvements in agriculture, and the consequent with advantage to themselves, to the benefit of drainage of the land, together with the great use made proprietors, and the general improvement of our
of it in medicine, have of late years rendered it of country."
less frequent occurrence.
On this account great The remark of the Scotsman applies to other coun- quantities of leeches are imported; these chiefly come tries besides Scotland. Several of the lower ranges from Bordeaux and Lisbor of hills in England do not ascend to the altitude of
The prevailing colour of the Medicinal Leech apLeadhills, and a lower latitude the region of pro-pears to vary according to the nature of the soil on fitable cultivation will necessarily ascend higher, and which it is found. In Winter the Leech retires to probably in proportion, cæteris paribus, to the range waters of considerable depth, and seeks shelter in the of isothermal lines, or to the height of the curve mud at the bottom; but in the Summer it appears of congelation in that latitude.
to delight in shallow pools, basking, as it were, in the "The Duke of Athol has ascertained that whilst warmth of the sun : but if the water it frequents is the Scotch fir thrives only at an elevation below 900 in danger of being dried up by the Summer-heat, the feet in the north of Scotland, the larch ascends to Leech buries itself in the mud at a considerable 1600 feet, and may ascend higher.” The same fact I depth. Just before a thunder-storm, Leeches appear have often observed at Leadhills, for there Scotch firs much agitated, and rise frequently to the surface of will not grow, and all other trees are stunted, ex
the water; this, therefore, is considered by the leechcepting larches, which grow luxuriantly when pro-gatherers as a favourable time for collecting them. tected. What a wide field for the cultivation of tim
The property by which a Leech anticipates thunder, ber, both in England and Scotland, does not this has induced some persons to employ it as a species of discovery of the Duke of Athol's at once disclose ? barometer; but its indications are very uncertain. The unprofitable heaths of Scotland, when they are The Medicinal Leech appears during its whole life not cultivated, may be adorned with wood; and to exist on the blood or other juices of the creatures almost all the hills of England may have larches on whose body it fixes itself; this is not the case growing upon their summits. Instead of importing with the horse-leech, which lives entirely on the larve timber from other countries, we may then have more of aquatic insects, worms, &c.; so that the common than we require; and thus obtain new resources, from idea of the danger of the bite of the horse-leech is being the exporting nation.
without foundation. [Magazine of Popular Science.]
The horse-leech is exceedingly voracious, not only swallowing worms, tadpoles, &c., but even preying upon its own species. Sixty-five horse-leeches were placed in a glass vessel, and in five days the number
was reduced to fifty-two, and not a vestige of those last thou heard of a shell on the margin of ocean, Whose pearly recesses the echoes still keep
that were missing was to be discovered. Of the music it caught when, with tremulous motion,
A number of this species of Leech, inhabiting the It joined in the concert poured forth by the deep ?
water that supplied a trough in which a tench had And fables have told us, when far inland carried,
been placed, fixed themselyes to different parts of the To the waste sandy desert, or dark ivied cave,
body of the fish, and so effectually was the poor tench In its musical chambers some murmurs have tarried
annoyed, that it was soon deprived of life. It learned long before of the wind and the wave.
From these habits it would appear, that the name Oh! thus should our spirits, which bear many a token
of Hirudo sanguisuga, (the blood-sucking leech,) has They are not of earth, but are exiles while here,
been improperly applied to the horse-leech; on this Preserve in their banishment, pure and unbroken,
account a recent author has suggested the name of Some sweet treasured notes of their own native sphere. Hirudo vorar, (the voracious leech,) as being more Though the dark clouds of sin may at times hover o'er us,
suitable to its nature. And the discords of earth may their melody mar,
The teeth, or rather piercers, with which the Leech Yet to spirits redeemed some faint notes of that chorus, is furnished, are three in number, of a hard gristly Which is borne by the blessed, will be brought from afar ! substance, and so placed, with regard to each other,
as to meet in the centre at equal angles; these piercers
are thrust into the skin when the animal attaches It is well known that time once passed never returns, and itself; not by one plunging effort, but by constantly that the moment which is lost, is lost for ever. Time there- scratching or sawing upon the surface (assisted at the fore ought, above all other kinds of property, to be free from invasion; and yet there is no man who does not claim
same time by the sucking action of the lips); in this the power of wasting that time which is the right of others. manner they gradually become buried in the skin, This usurpation is so general, that a very small part of the and there remain as long as the creature retains its year is spent by choice; scarcely anything is done when it bold; this movement of the piercers occasions the is intended, or obtained when it is desired. Life is con- gnawing pain felt for the first two or three minutes tinually ravaged by invaders; one steals away an hour, and after the Leech has commenced operation. another a day-one conceals the robbery by hurrying us
Leeches are at times so scarce and valuable, that into business, another by deluding us with amusement; the depredation is continued through a thousand vicissitudes great care has been taken in preserving them in a of tumult and tranquillity, still having lost all, we can lose healthy state and fit for use. The principal art in no more,JOHNSON.
managing them consists in placing them in vessels
THE SEA SHELL.
THE MEDICINAL LEECH.
sufficiently large, keeping the water clear, and in re- The country about La Brenne is, perhaps, the most un moving those which are unhealthy as soon as they interesting in France; the people are miserable cooking,
the cattle wretched, the fish just as bad, but the leeches are are discovered.
admirable. If ever you pass through La Brenne, you will see a man pale and straight-haired, with a woollen cap on his head, and his legs and arms naked; he creeps along the borders of a marsh, among the spots left dry by the surrounding waters, but particularly wherever the vegetation seems to preserve the subjacent soil undisturbed; this man is a leech-fisher. To see him from a distance, his woe-begone aspect, his hollow eyes, his livid lips, his singular gestures, you would take him for a patient who had left his sick bed in a fit of delirium. If you observe him every now and then raising his legs and examining them one after the other, you might suppose him a fool; but he is an intelligent
leech-fisher. The Leeches attach themselves to his legs Leeches, when applied to the skin, frequently show
and feet as he moves among their haunts; he feels their little inclination to bite, and many plans have been
presence from their bite, and gathers them as they cluster resorted to, to induce them to commence operations, about the roots of the bull-rushes and sea-weeds, or beneath such as bathing the part with milk, &c.; but these the stones covered with green and glutinous moss. Some methods may be considered useless, and the best plan repose on the mud, while others swim about; but so slowly
that they are easily gathered with the hand. In a favourappears to be, to wash the part clean, and this is the more necessary when any embrocation has been pre- hours, to stow ten or twelve dozen of them in the little bag
able season it is possible, in the course of three or four viously applied ; but the surest way is to puncture which the gatherer carries on his shoulder. Sometimes the place slightly, so as to cause the blood to appear. you will see the leech-fisher armed with a kind of spear or If the little surgeon, before it is fully gorged, appears harpoon; with this he deposits pieces of decayed animal lazy and unwilling to proceed, it can be usually matter in places frequented by the leeches; they soon gather roused by being sprinkled with a little co.d water.
round the prey, and are presently themselves gathered into After a leech has fallen off, it is usual to sprinkle
a little vessel half full of water; such is the leech fishery in
Spring. salt on it to induce it to disgorge the blood it has In Summer the Leech retires into deep water; and the swallowed ; but as the salt frequently blisters its fishers have then to strip themselves naked, and walk imbody, it has been recommended by Dr. Johnson of mersed up to the chin. Some of them have little rafts to Edinburgh, from whose work on the Leech, we have go upon; these rafts are made of twigs and rushes, and it obtained most of the preceding information, to apply is no easy matter to propel them among the weeds and a small portion of vinegar to the head of the Leech, aquatic plants. At this season, too, the supply in the pools
is scanty, the fisher can only take the few that swim within instead of salt.
his reach, or those that get entangled in the structure of his It was long a matter of dispute as to whether raft. Leeches were produced from eggs or born alive, but it It is a horrid trade in whatever way it is carried on. The is now ascertained that the ova are developed in a leech-gatherer is constantly more or less in the water, singular case, having some resemblance to the cocoon breathing fog and mist, and fetid vapours from the marsh; of a silk-worm. The following engraving represents Some indulge
in strong liquors to keep off the noxious in
he is often attacked with agues, catarrhs, and rheumatism. this case, of its natural size : fig. 1. shows the perfect fluence, but
they pay for it in the end by disorders of other case or cocoon, and fig. 2. the aame opened, with the kinds. But with all its forbidding peculiarities, the leech young Leeches contained within it; it is said that, at fishing gives employment to many hands; if it be pertimes, there are as many as thirteen or fourteen in nicious, it is also lucrative. Besides supplying all the neigh
This cocoon is formed by the parent bouring medical men, great quantities are exported, and animal, and by it deposited in the mud or clay which there are regular traders engaged for the purpose. Henri
Chartier is one of those persons, and an important per: composes the bed of the pool it inhabits.
sonage he is when he comes to Meobecq or its vicinity; his Fig. 1.
arrival makes quite a fête, all are eager to greet him.
Among the interesting particulars which I gathered in La Brenne relative to the Leech-trade, I may mention the following. One of the traders, what with his own fishing and that of his children, and what with his acquisitions from the carriers, was enabled to hoard up 17,500 leeches in the course of a few months; he kept them deposited in
a place, where in one night they all became frozen into a The fact of the young Leech being produced from
But the frost does not immediately kill them; these cocoons, although only latterly ascertained by indeed bear very hard usage. I am told by one of the
they may generally be thawed into life again. They easily naturalists, was long since well known to the dealers carriers that he can pack them, as closely as he pleases, in in Leeches on the French coast, who avail themselves the moist sack which he ties behind his saddle, and some of this knowledge of their habits, to multiply them times he stows his cloak and boots on the top of his sack, for the purpose of sale.
The trader buys his Leeches without distinction, big and It was by these means the leech-dealers of Bretagne, and little
and black, all the same; but he afterwards particularly in Finisterre, replenished the ponds in which
sorts them for the market. Those are generally accounted they preserved those leeches which were intended for the
the best which are of a green ground, with yellow stripes Paris market
along the body. About the month of April or May, according to the nature of the season, they send out labourers, provided with A GOOD conscience is more to be desired than all the spades and baskets, to the little muddy marshes, where riches of the East. How sweet are the slumbers of him, they are known to exist in abundance. These workmen
who can lie down on his pillow and review the transactions then set about removing those portions of mud that are
of every day, without condemning himself! A good code known to contain cocoons, which are afterwards deposited science is the finest opiate.-— Knox. in sheets of water previously prepared for their reception; here the young leeches quit the cocoons, and are allowed to remain six months, when they are removed to larger ponds.
LONDON: The subjoined graphic account of the mode of JOHN WILLIAM PARKER, WEST STRAND. taking Leeches at another part of the French coast,
PUBLISHED IN WEEKLY NUMBERS, PRICE ONE PENNY, AND IN MONTHLY PATI is translated from the Journal des Hôpitaux :
Sold by all Booksellers and Newscenders in the Kingdom
THE ROTUNDA, OR REPOSITORY, AT WOOLWICH. The town of Woolwich, at present so well known on state, at the time of filling them with the melted account of its naval arsenal, was originally a small metal. From this time Woolwich gradually assumed fishing village of little note. Its advantageous situa- the character of a naval arsenal. tion on the banks of the Thames, being only eight The appearance of the town itself, at least of the miles from London, and more particularly the great older buildings, is far from prepossessing; that part, depth of the river at this spot, capable at all times of however, which adjoins Charlton and the common, the tide of floating the largest vessels, have been the must be excluded from this censure. cause of its gradual increase in importance. These It is to the public buildings that Woolwich owes favourable circumstances were noticed as far back as its importance. The dock-yard extends along the the reign of Henry the Seventh, who had a large bank of the river, for a mile in length: it contains, vessel built here, of a thousand tons burden. It was besides the dwellings for the officers, a smithery, in not, however, until the time of Henry the Eighth that which there are two steam-engines, one of twenty and any regular dock-yard was established at Woolwich. the other of fourteen horse power, the largest being After his death the establishment was greatly increased employed in working two large lift-hammers, weighing by Queen Elizabeth, and since then it has been pro- nearly four tons each ; these are raised by machinery, gressively improved and enlarged. In the reign of nine inches at each stroke, from thirty to fifty times Charles the First, a large vessel was built, of 1637 tons in a minute : these hammers are employed in forging burden, which was formidably armed, and superbly large anchors, and other iron work connected with gilded: from its destructive powers, it was called by ship building; the smaller engine is attached to the the Dutch, with whom we were then at war, the blowing apparatus, by which the fires of the forges “ Golden Devil."
are excited. Woolwich, up to the time of George the First, con- There are two dry docks, one double, and several tinued simply noted for its dock-yard ; but in the reign slips, in which vessels of the largest size are built. of that monarch, the foundry for cannon was removed A large basin, 400 feet long, and 290 feet in breadth, from Moorfields, where it had previously been carried is also within the enclosure of the dock-yard, together on, to the Warren that adjoins the town. The cause with a mast-pond, a boat-pond, and numerous storeof its removal was a dreadful accident, which occurred houses, and other buildings necessary for the work, by the explosion of the moulds, which were in a damp | men. Vol. XIII,