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and it is now become usual for chemists, among their other experiments on minerals, to mention their habitudes with the blow pipe.

The fluxes which have obtained the ge. neral sanction of chemists, on account of the extensive use they have been applied to by Bergman, are phosphoric acid in the dry or glassy state, soda, and borax or the native borate of soda.

LABOUR, in general, denotes a close application to work or business. Among seamen a ship is said to be in labour when she rolls and tumbles very much, either a hull under sail, or at anchor. It is also spoke of a woman in travail, or child-birth. See MIDWIFERY.

LABRADOR stone, in mineralogy, is of a grey colour, passing into a dark ash. It exhibits, however, under certain circumstances, a great variety of colours, as blue, green, yellow, red, and brown, in their different shades. It shows, likewise, spotted and striped delineations. Sometimes the same spot if held in different directions changes its colour from blue to green, &c. The beautiful colours seldom extend over a whole piece; in general, they show themselves only in large and smaller spots and patches. Different colours are presented according as the piece is held between the light and the eye, or the eye and the light. It occurs massive, in blunt edged and rolled pieces. Its principal fracture is shining, passing into splendent. Specific gravity is about 2.7. It runs into a white enamel, with addition before the blow-pipe. The constitutent parts are

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It makes a part of certain kinds of green stone, and is accompanied with mica and shorl, though seldom with iron pyrites. It was originally discovered by the Moravians, in the island of St. Paul, on the coast of Labrador, where it is still to be met with in plenty, also in some parts of Denmark and Norway, and near the romantic Lake of Baikel in Siberia. It is used for many ornamental purposes.

LABRUS, in natural history, a genus of fishes of the order Thoracici. Generic cha racter: teeth strong and sharp; the grin

ders sometimes convex and crowded; lips thick and doubled; rays of the dorsal fin in several species prolonged into soft processes; gill-covers unarmed and scaly. There are ninety-eight species enumerated by Shaw, of which we shall notice merely the following: L. scarus, is about the length of twelve inches, and is found in the Mediterranean in immense shoals. It was well known to the ancients, and highly admired by them, being considered as one of the most luxurious dainties. For a representation of the blue-finned Labrus, see Plate V. fig. 2. LABYRINTH, in anatomy, the internal cavity of the ear, so called from sinuosities and windings. See EAR.

LABYRINTH, in gardening, a winding mazy walk between hedges, through a wood or wilderness. The chief aim is to make the walks so perplexed and intricate that a person may lose himself in them, and meet with as great a number of disappointments as possible. They are rarely to be met with except in great and noble gardens, as Versailles, Hampton court, &c. There are two ways of making them; the first is with single hedges: this method has been practised in England: and these may, indeed, be best, where there is but a small spot of ground allowed for making them; but where there is ground enough the double is most eligible. Those made with double hedges, with a considerable thickness of wood between them, are approved as much better than single ones: this is the manner of making them in France and other places; of all which that of Versailles is allowed to be the noblest of its kind in the world. It is an error to make them too narrow; for that makes it necessary to keep the hedges close clipped: but if, according to the foreign practice, they are made wide, they will not stand in need of it. The walks are made with gravel usually set with horn-beam: the pallisades ought to be ten, twelve, or fourteen feet high: the horn-beam should be kept cut, and the walks rolled.

LAC, gum, in chemistry, is a very singular compound, prepared by the female of a very minute insect, the coccus lacca, found on some trees in the East Indies, particularly the banyan fig. The insect is nourished by the tree, fixing itself upon the twigs and extremities of the succulent branches, where it deposits its eggs, which it glues to the branch by a red liquid, the outside of which hardens by the air, and serves as a cell for the parent insect. This increases in size,

and the young insects at first feed upon the enclosed liquid, and after this is expended they eat through the coat, leaving a hollow red resinous bag which is "stick-lac." The best lac is procured from the province of Acham, but it is obtained in great plenty on the uncultivated mountains on each side of the Ganges. There are four kinds of lac, viz. "stick-lac," which is lac in its natural state, without any preparation; "seed-lac," which is stick-lac broken into small lumps, and granulated; "lump-lac," which is seedlac liquified by fire; "shell-lac," which is a preparation of the stick-lac. By a number of very accurate experiments made by Mr. Hatchett, it is found that lac consists of a colouring extract, of resin, gluten, and wax; all of them in intimate combinations: the proportions of the stick-lac are as follow:

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as that of gold and silver. The pattern of the lace is fixed upon a large round pillow, and pins being stuck into the holes or openings in the pattern, the threads are interwoven by means of a number of bobbins made of bone or ivory, each of which contains a small quantity of fine thread, in such a manner as to make the lace exactly resemble the pattern. There are several towns in England, and particularly in Buckinghamshire, that carry on this manufacture; but vast quantities of the finest laces have been imported from Flanders.

LACERTA, the lizard, in natural history, a genus of Amphibia, of the order Reptiles. Generic character: body fourfooted, tailed, naked and long, having no secondary integument; legs equal. There are, according to Gmelin, eighty-one spe cies, of which the following are principally deserving of attention. L. crocodilus or the crocodile, is a native both of Africa and Asia, but is most frequently found in the former, inhabiting its vast rivers, and particularly the Niger and the Nile. It has occasionally been seen of the length of even thirty feet, and instances of its attaining that of twenty are by no means uncommon. It principally subsists on fish, but such is its voracity, that it seizes almost every thing within its reach. The upper part of its body is covered with a species of armour, so thick and firm, as to be scarcely penetrable by a musket ball, and the whole body exhibits the appearance of an elaborate covering of carved work. It is an oviparous animal, and its eggs scarcely exceed in size those of a goose. These eggs are regarded as luxuries by the natives of some countries of Africa, who will also with great relish partake of the flesh of the crocodile itself. When young, the small size and weak state of the crocodile prevent its being injurious to any animal of considerable bulk or strength, as those which have been brought living to England have by no means indi

LACCIC acid, in chemistry, a white or yellowish production of insects, called whitelac. Some of this substance, brought from Madras, was analyzed by Dr. Pearson, who found that it bore a considerable analogy to bees-wax. A full account of Dr. Pearson's experiments may be seen in the eighty-cated that ferocious and devouring characfourth volume of Philos. Trans. The component parts of this acid are supposed to be carbon, hydrogen, and oxygen.

LACE, in commerce, a work composed of many threads of gold, silver, or silk, interwoven the one with the other, and work ed upon a pillow with spindles, according to the pattern designed. The open-work being formed with pins, which are placed and displaced as the spindles are moved.

LACE, bone, a lace made of fine linen, thread, or silk, much in the same manner

ter which they have been generally described to possess, a circumstance, proba bly, owing to the change of climate, and the reducing effect of confinement. In its native climate its power and propensity for destruction are unquestionably great, and excites in the inhabitants of the territories near its haunts a high degree of terror. It lies in wait near the banks of rivers, and with a sudden spring, seizes any animal that approaches within its reach, swallowing it by an instantaneous effort, and then rushing

back into its watery recesses, till renewed appetite stimulates the renewal of its insidious exertions. These animals were occasionally exhibited by the Romans among their collections of the natural wonders of the provinces, and Scaurus and Augustus are both recorded to have entertained the people with the sight of these new and formidable objects. It is reported by some travellers, that crocodiles are capable of being tamed, and are actually kept in a condition of harmless domestication at the grounds and artificial lakes of some African princes, chiefly as appendages of royal splendour and magnificence. A single negro will often attack a crocodile, and by spearing it between the scales of the belly, where it is easily penetrable, secure its destruction. In some regions these animals are hunted by dogs, which, however, are carefully disciplined to the exercise, and are armed with collars of iron spikes. Aristotle appears to have been the first who asserted that the under jaw of the crocodile was immovable, and from him the idea was transmitted and believed for a long succession of ages. But the motion of the jaw in this animal is similar to that of all other quadrupeds. The ancients also thought it destitute of a tongue, an idea equally false. The tongue, however, is more fixed in this than in most animals to the sides of the mouth, and less capable therefore of being protruded. The eggs of the crocodile are deposited on the mud or sand of the banks of rivers, and, immediately on being hatched, the young move towards the water, in their passage to which, however, vast numbers are intercepted by ichmeamons and birds, which watch their progress. See Amphibia, Plate I. fig. 4.

L. alligator, the alligator, differs from the former species principally in being more smooth on the upper part of the head, and on the snout being much wider and flatter, and-rounder at the end. It grows to the length of eighteen feet, and abounds particularly in the torrid zone, but it is found so far north as the river Neus in North Carolina. It is met with both in the fresh and salt parts of rivers, and amidst the reeds along the banks, lurks in ambush for its prey, seizing upon dogs and cattle which approach within the reach of its fatal bound. Alligators are equally formidable in their appearance, and ferocious in their disposi tions, seizing both man and beast with al most indiscriminating voracity, and pulling them to the bottom to lessen their means of

resistance, and devour them with less inruption. By the close union of the ver tebræ, this animal can proceed with celerity only in a straight forward direction, so that the intended victims pursued by them, are enabled to elude this destination by lateral and cross movements. But though the alligator is deficient in flexibility, it supplies this defect in a great degree by sagacity or cunning, and appearing on the surface of the water like the stock of a tree, he thus attracts various animals within its grasp. Fowls, fishes, and turtle, all are drawn, whether by curiosity or for convenience, towards this object, supposed completely harmless, but from which the jaws of destruction are instantly opened to devour them. Alligators are said to swallow stones and various other substances incapable of affording nourishment, merely to prevent the contraction of their intestines, and thus allay their hunger; and Catesby observes, that ou opening a great number, he has seen nothing but clumps of light wood and pieces of pine tree coal (in one instance a piece of the weight of eight pounds) worn by attri tion to a surface perfectly smooth, implying that they had long remained in their bodies. Their eggs are deposited on the banks of rivers, and sometimes in a nest composed of vegetables with considerable care, and are hatched by the sun, and the young ones are not only devoured by fishes and birds, but become the victims often of their own voracious species. In Carolina they seldom attack men or large cattle, but are formida ble enemies to hogs. From October to March they continue in the sequestered caverns of the river banks in a state of torpor, re-appearing in the spring with the most violent and terrific noises. Some parts of them are used by the Indians for food, and the flesh is of an attractive whiteness, but has a very strong flavour of musk. The growth of this animal, and of the crocodile, is extremely slow, and both are imagined to be long lived. See Amphibia, Plate I. fig. 2.

L. iguana, or the great American guana, is found in various parts of America and the West Indies. Its colour is generally green. Its back exhibits the appearance of a saw, and it is distinguished by a pouch under the throat, which it is able to extend or contract at pleasure, and which gives it occasionally an appearance truly formidable. It is formidable, however, only in appearance, being in fact perfectly inoffensive. Its general length is from three to five feet; it inhabits rocks and woods, and subsists ou ve.

getable food and certain species of insects. The guanas deposit their eggs (which have no testaceous covering, and are much valued for food) in the earth where they may be warmed by the beams of the sun, and leave them to be matured solely by its influence. The natives of the Bahamas train dogs to the pursuit of these animals, and a well disciplined dog will take them alive, in which case they are carried for sale to the markets of Carolina in the holds of vessels; those which are destroyed or lacerated by the dogs, are salted and barrelled, and kept for the home consumption. Their flesh is reported to be easily digestible, delicate, and well flavoured. They will keep under water for nearly an hour; when they swim, their feet are kept close to their bodies, and they appear to produce and regulate their motions merely by their tails. Whatever they eat they swallow whole. They have been kept without food a very considerable time. Their colour is much affected by the state of the weather, or the dampness or dryness of their habitation. They may be easily tamed if taken young.

L. basiliscus, or the basilisk, is particu larly distinguished by a broad wing-like process, elevated along the whole length of its back, somewhat similar to the fins of fishes, and which is capable, at the pleasure of the animal, of being extended or contracted. It lives almost solely in trees, feeding upon insects, and though somewhat terrific in appearance, is as harmless as any of the lizard tribe. It is found most frequently in South America, generally about a foot and a half long, swims with great ease, and moving among the branches of the trees with extreme agility, sometimes apparently with a short flight, which is aided by the remarkable process above mentioned, on its back. The basilisk of antiquity, whose bite was supposed to be more speedily mortal than that of any other creature, and whose look even carried destruction with it, is to be ranked with the fabulous monsters, which in the prevailing ignorance of nature that attended those times, were amply supplied by a poetic imagination. See Amphibia, Plate I. fig. 3.

L. monitor, or the black lizard, measures frequently four and sometimes five feet, being one of the largest as well as the most elegant of the tribe. It is found principally in woody and moist situations in South America, and is reported to give indications of attachment and gratitude to those by whom it has been fed, and familiarised to be as VOL. IV.

mild in its manners and temper as it is ele gant in its form.

Its

L. agilis, or the green lizard, is abundant in all the warmer latitudes of Europe, some times attaining the length of more than two feet, but in general not exceeding one. colouring is more beautiful than that of any of its tribe in this quarter of the world. About the southern walls of gardens, it is particularly seen pursuing insects with great alertness and dexterity, and both in attack and escape its agility is truly admirable. It may to a certain degree be tamed and familiarised, and in this state is by many considered not only as a perfectly harmless, but as a favourite animal.

L. chamæleon, the chameleon, is generally of the length of ten inches without the tail, which is equally long. Its food consists of insects, which it procures by protruding the tip of its tubular and lengthened tongue with inconceivable celerity, and never failing to retract with it the prey at which it was darted. In India and Africa, and various other parts of the world, these animals are found in great abundance. They are perfectly inoffensive, and can endure a long abstinence, from which latter circumstance the idea of their living upon air alone, may not unnaturally have been derived. They occasionally retain the air in their lungs for a very considerable time, and thus assume an appearance of fullness and fleshiness which is in perfect contrast to that which they will suddenly exhibit, in consequence of the total expulsion of the air from the lungs, during which they are collapsed and seemingly emaciated. A change of colour is sometimes observed in many of the lizard tribe, but particularly so in the chameleon; but the long prevailing idea of the adaptation of its colour to that of any substance with which it is surrounded is totally groundless. Its varieties in this respect appears to extend (in consequence principally, of varied health or temperature) from its natural green-grey into very pale yellow, with irregular patches of red. When exposed to the sun, considerable changes in the shading and patching of its colours are observable; and when, after being wrapped in white linen by some members of the French Academy it reappeared within two or three minutes, it partook somewhat, but very far from completely of the colour of it. On being folded up in substances of various other different colours, it borrowed neither of them, and exhibited no interesting change. The

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movements of the chameleon are extremely slow, and in passing from branch to branch its tail is coiled for security round one till its feet have been extended to the other.

L. salamandra, or the salamander, is of a deep brilliant black colour, varied with irregular patches of bright yellow. It is found in various parts of France, Germany, and Italy, abounding particularly in moist and woody situations, and making its appearance chiefly during rain. In winter it secludes itself in clefts, or hollow trees. It is about seven inches long, lives principally upon insects and snails, can subsist by water as well as land, is slow in its movements, and lethargic in its habits. The idea of its being capable of enduring fire without injury, can be accounted for, merely from its possessing a power of exuding in any state of irritation a white and glutinous substance, which must of course tend to render the application of fire less immediately destructive to it than to some other animals, and considering what trifling causes have led, in innumerable cases to important inferences, this fact may probably have given rise to the notion of the salamander being insusceptible of destruction, and even of injury in the midst of flames. The idea of its poisoning any large animal by its bite is equally exploded. The common lizard, however, is stated to have been poisoned in consequence of the bite of the salamander, from some particular fluid contained in the skin of the latter. The salamander produces its young living, hatched from internal eggs, and frequently upwards of thirty in

number.

L. aquatica, or the common water newt, is generally about three inches and a half in length, and is found in this country in almost all its stagnant waters. Newts frequently cast their skins with the most complete wholeness, even to the exquisitely delicate and filmy coverings of the eye. In the power of reproduction they resemble the cancer genus. The loss of a leg is reported by Dr. Blumenbach to be easily repaired by renovation, and it is added that the same circumstance occurs with respect to the eyes. The tenaciousness of life exhibited by these animals is remarkable. They have often been found inclosed in large masses of ice, in which they must have been confined for days, weeks, or, even in some instances, for months; and, on being freed from their prison, have soon displayed all the alertness and vigour of perfect health.

;

LACHENALIA, in botany, a genus of the Hexandria Monogynia class and order. Natural order of Coronaria. Asphodeli, Jussieu. Essential character: corolla sixparted; the three outer petals difform capsule three-winged; cells many-seeded; seeds globular, affixed to the receptacle. There are twelve species, all bulbous rooted plants, and natives of the Cape of Good Hope.

LACHES, in law, signifies slackness or negligence; as when we say, "there is a laches of entry," it means the same as to say, there is lack or neglect of entry.

LACHNEA, in botany, a genus of the Octandria Monogynia class and order. Natural order of Vepreculæ. Thymelææ, Jussieu. Essential character: calyx none; corolla four-cleft, with an unequal border; seed one, like a berry. There are two species, viz. L. eriocephala, woolly-headed lachnæa; and L. conglomerata, clusterheaded lachnæa; these are both shrubs, and natives of the Cape of Good Hope.

The

LACHRYMAL, in anatomy, an appellation given to several parts of the eye, from their serving to secrete the tears. lachrymal gland is situated in the orbit above the smaller angle, and its excretory ducts under the upper eye-lid: these are much more easily demonstrated in the eye of an ox than in a human one.

LACIS, in botany, a genus of the Poly. andria Digynia class and order. Essential character: calyx none; corolla none; filaments winged on both sides below; recep tacle girt, with twelve spines; capsule ovate, eight-streaked, one-celled, two-valved, many-seeded. There is but one species, viz. L. fluviatilis ; this plant is called by the natives mourerou; it is a native of Guiana, and has been found only on the rocks of the great cascade of the river Sinemari; it is always under water, except the flowering branches; it is attached to the rocks by packets of small fibres.

LACISTEMA, in botany, a genus of the Monandria Digynia class and order. Essential character: calyx scale of the ament; corolla four-parted; filaments bifid; berry pedicelled, one-seeded. There is but one species, viz. L. myricoides, found in Surinam and Jamaica.

LACTATES, combinations of earths and alkalies, &c. with the LACTIC acid, which

see.

LACTEAL vessels, in anatomy, fine sub. Ule canals situated in the intestines and me

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