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Lieutenant

LIEUTENANT-Colonel. See COLONEL. LIEUTENANT-General. See GENERAL.

Licon- the name of Mádera, who for several weeks dissembled troops, and companies. Under the lords-lieutenants, Lieutenant Kieou his high rank, and, in the habit of the lower orders, at- are deputy-lieutenants, who have the same power; tracted the notice of every one by his singular curiosity these are chosen by the lords-lieutenants, out of the and intelligence, and ingratiated himself with every principal gentlemen of each county, and presented to one by his extreme good humour, kindness, and habits the king for his approbation. of accommodation. In less than a month, he had acquired so much English as to be able to converse very intelligibly, and, on many occasions, to perform the part of an interpreter; and, in a far shorter time, he had so perfectly familiarized himself with our usages, as to have no appearance whatever of awkwardness or embarrassment in the society of the travellers. He and the other chiefs cried bitterly at parting with their English friends.

Their religion, it seems, is that of Buddh or Fo; but it seems to occupy scarcely any share of their regard, and the priests are universally regarded as the lowest and least respected class in the community. These unhappy men are condemned to celibacy, and seemed to have no occupation but to sweep the temple, and keep the walks in the garden in order.

LIEUTAUD, DR JOSEPH, counsellor of state and first physician at the court of France, was born at Aix in Provence, and resided principally there till he took the degree of doctor of medicine. After this he prosecuted his studies for some years at Montpelier. He returned to Aix, where he soon acquired extensive practice, and became eminent for literary abilities. He resided there till the year 1750, when he was invited to act as physician to the royal infirmary at Versailles. There he practised with such reputation and success, that he soon arrived at the head of his profession; and in the year 1774, upon the death of M. Senac, he was appointed archiater. His extensive engagements in practice did not prevent him from cultivating the science of medicine in all its branches, and from freely communicating to others the result of his own studies. He published many valuable works; amongst which the following may be accounted the most remarkable. 1. Elementa Physiologia. 2. Precis de la Medicine. 3. Pratique Precis de la Matiere Medicale. 4. Essais Anatomiques. 5. Synopsis Universæ Praxeos Medicina. 6. Historia Anatomico-Medica. He died at Versailles in 1780, aged 78 years.

LIEUTENANT, an officer who supplies the place and discharges the office of a superior in his absence. Of these, some are civil, as the lords-lieutenants of kingdoms, and the lords-lieutenants of counties; and others are military, as the lieutenant-general, lieutenant-colonel, &c.

Lord-LIEUTENANT of Ireland, is properly a viceroy; and has all the state and grandeur of a king of England, except being served upon the knee. He has the power of making war and peace, of bestowing all the offices under the government, of dubbing knights, and of pardoning all crimes exccat high treason; he also calls and prorogues the parliament, but no bill can pass without the royal assent. He is assisted in his government by a privy-council; and on his leaving the kingdom, he appoints the lords of the regency, who govern

in his absence.

Lords-LIEUTENANTS of Counties, are officers, who,. upon any invasion or rebellion, have power to raise the militia, and to give commissions to colonels and other officers, to arm and form them into regiments,

LIEUTENANT, in the land service, is the second commissioned officer in every company of both foot and horse, and next to the captain, and who takes the command upon the death or absence of the captain.

LIEUTENANT of Artillery. Each company of artillery hath four; I first and 3 second lieutenants. The first lieutenant hath the same detail of duty with the captain, because in his absence he commands the company he is to see that the soldiers are clean and neat; that their clothes, arms, and accoutrements, are in good and serviceable order; and to watch over every thing else which may contribute to their health. He must give attention to their being taught the exercise, see them punctually paid, their messes regularly kept, and to visit them in the hospitals when sick. He must assist at all parades, &c. He ought to understand the doctrine of projectiles, and the science of artillery, with the various effects of gunpowder, however managed or directed; to enable him to construct and dispose his batteries to the best advantage; to plant bis cannon, mortars, and howitzers, so as to produce the greatest annoyance to an enemy. He is to be well skilled in the attack and defence of fortified places; and to be conversant in arithmetic, mathematics, mechanics, &c.

Second LIEUTENANT in the Artillery, is the same as an ensign in an infantry regiment, being the youngest commissioned officer in the company, and must assist the first lieutenant in the detail of the company's duty. His other qualifications should be equal with those of the first lieutenant.

LIEUTENANT of a Ship of War, the officer next in rank and power to the captain, in whose absence he is accordingly charged with the command of the ship, as also the execution of whatever orders he may have received from the commander relating to the king's service.

The lieutenant who commands the watch at sea, keeps a list of all the officers and men thereto belonging, in order to muster them when he judges it expedient, and report to the captain the names of those who are absent from their duty. During the night watch, he occasionally visits the lower decks, or sends thither a careful officer, to see that the proper centinels are at their duty, and that there is no disorder amongst the men; no tobacco smoked between decks, nor any fire or candles burning there, except the lights which are in lanthorns, under the care of a proper watch, on particular occasions. He is expected to be always upon deck, in his watch, as well to give the necessary orders with regard to trimming the sails and superintending the navigation, as to prevent any noise or confusion; but he is never to change the ship's course without the captain's directions, unless to avoid an immediate danger.

The lieutenant, in time of battle, is particularly to see that all the men are present at their quarters where they have been previously stationed according to the regulations made by the captain. He orders and ex

horts

Lieutenant horts them everywhere to perform their duty, and acquaints the captain at all other times of the misbehaviour of any person in the ship, and of whatever else concerns the service or discipline.

Life.

The youngest lieutenant in the ship, who is also styled lieutenant at arms, besides his common duty, is particularly ordered, by his instructions, to train the seamen to the use of small arms, and frequently to exercise and discipline them therein. Accordingly his office, in time of battle, is chiefly to direct and attend them; and at all other times to have a due regard to the preservation of the small arms, that they be not lost or embezzled, and that they are kept clean and in good condition for service.

LIEUTENANT Reformed, he whose company or troop is broke or disbanded, but continued in whole or half pay, and still preserves his right of seniority and rank in the army.

LIFE, is peculiarly used to denote the animated state of living creatures, or the time that the union of the soul and body lasts.

The Prolongation of LIFE is made by Lord Bacon one of the three branches of medicine; the other two relating to the preservation of health, and the cure of diseases. See MEDICINE.

The theory of prolonging life he numbers among the desiderata. Some means or indications that seem to lead to it, he lays down as follow:

Things are preserved in two manners; either in their identity, or by reparation. In their identity; as a fly or ant in amber; a flower, fruit, or wood, in a conservatory of snow; a dead carcase in balsams. By reparation; as a flame, or a mechanical engine, &c. To attain to the prolongation of life, both these methods must be used. And hence, according to him, arise three intentions for the prolongation of life; Retardation of consumption, proper reparation, and renovation of what begins to grow old.

Consumption is occasioned by two kinds of depredation; a depredation of the innate spirit, and a depredation of the ambient air. These may be each prevented two ways; either by rendering those agents less predatory, or by rendering the passive parts (viz. the juices of the body) less liable to be preyed on. The spirit will be rendered less predatory, if either its substance be condensed, as by the use of opiates, grief, &c.; or its quantity diminished, as in spare and monastic diets; or its motion calmed, as in idleness and tranquillity. The ambient air becomes less predatory, if it be either less heated by the rays of the sun, as in cold climates, in caves, mountains, and anchorets cells; or be kept off from the body, as by a dense skin, the feathers of birds, and the use of oils and unguents without aromatics. The juices of the body are rendered less liable to be preyed on, either by making them harder, or more moist and oily; harder, as by a coarse sharp diet, living in the cold, robust exercises, and some mineral baths: moister, as by the use of sweet foods, &c. abstaining from salts and acids; and especially by such a mixture of drink as consists wholly of fine subtile particles, without any acrimony or acidity. Reparation is performed by means of aliment; and alimentation is promoted four ways: By the concoction of the viscera, so as to extrude the aliment: By exciting the exterior parts to the attraction of the aliment; as

in proper exercises and frications, and some unctions Life, and baths: By the preparation of the food itself, so as Life-Boat. it may more easily insinuate itself, and in some measure anticipate the digestion; as in various ways of dressing meats, mixing drinks, fermenting breads, and reducing the virtues of these three into one: By promoting the act of assimilation itself, as in seasonable sleep, some external application, &c.

The renovation of what begins to grow old, is performed two ways: By the inteneration of the habit of the body; as in the use of emollients, emplasters, unctions, &c. of such a nature, as do not extract but impress: Or by purging off the old juices, and substituting fresh ones; as in seasonable evacuations, attenuating diets, &c.

The same author adds these three axioms: That the prolongation of life is to be expected, rather from some stated diets, than either from any ordinary regimen or any extraordinary medicines; more from operating on the spirits, and mollifying the parts, than from the manner of feeding; and this mollifying of the parts without is to be performed by substantials, impriments, and occludents. See LONGEVITY.

LIFE-Boat, a most important invention, consisting ia an improvement of the ordinary construction of a boat, by which it cannot be sunk in the roughest sea; so that it is peculiarly fitted for bringing off mariners from wrecks during a storm, and thus saving many valuable lives. The life-boat was first conceived at South Shields, in the county of Durham. A committee of the inhabitants of that town, who had often been the sad witnesses of many melancholy shipwrecks, in which by the ordinary means no relief could be given, in a public advertisement requested information on this subject, with models of boats which would be most proper for the purpose of saving persons from shipwreck. The committee, it would appear, employed Mr Greathead, a boat-builder in South Shields, who had with others presented the model of a boat for this purpose, to build the first boat, which upon trial was found fully to answer the purpose. Two claimants have since appeared for the honour of the invention, which according to Mr Farles, the chairman of the committee, in his letter to Mr Hails the supporter of one claim, belongs to two of the members themselves, namely Mr Farles himself and Mr Rockwood. The claimants above alluded to are Mr Greathead, and a Mr Wouldhave a painter in South Shields, and a very ingenious man, who also presented a model to the committee. The claim of the latter is keenly supported by Mr Hails, in a pamphlet published in 1806, two years after Mr Greathead's pamphlet containing the history and progress of the invention, and of the boats which he had built for the purpose, his application to parliament, and the premium of 1200l. which he received for the invention, &c. and four years after this application to parliament. It is true that in 1802, Mr Wouldhave and his friends asserted his claim in the Monthly Magazine, and in some provincial newspapers; but still this was one year after Mr Greathead's application for reward was made to parliament. But, without being at all understood to decide to whom the merit of the invention is due, we shall leave it to our readers to examine the evidence for themselves, and shall now proceed to give an account of the construction of the life-boat, of which 31 have been

Life-Boat. built by Mr Greathead, and sent to different parts of Britain, and the north of Europe. The following construction is according to Mr Greathead's plan : "The length thirty feet; the breadth ten feet; the depth, from the top of the gunwale to the lower part of the keel in midships, three feet four inches; from the gunwale to the platform (within) two feet four inches; from the top of the stems (both ends being similar) to the bottom of the keel, five feet nine inches. The keel is a plank of three inches thick, of a proportionate breadth in midships, narrowing gradually toward the ends, to the breadth of the stems at the bottom, and forming a great convexity downward; the stems are segments of a circle with considerable rakes; the bottom section, to the floor heads, is a curve fore and aft with the sweep of the keel; the floor timber has a small rise curving from the keel to the floor heads; a bilge plank is wrought in on each side next the floor heads, with a double rabbit or groove of a similar thickness with the keel, and on the outside of this are fixed two bilge-trees corresponding nearly with the level of the keel; the ends of the bottom section form that fine kind of entrance observable in the lower part of the bow of the fishing boat called a coble, much used in the north; from this part to the top of the stem, it is more elliptical, forming a considerable projection: the sides, from the floor heads to the top of the gunwale, flaunch off on each side, in proportion to about half the breadth of the floor; the breadth is continued far forward toward the ends, leaving a sufficient length of straight side at the top; the sheer is regular along the straight side, and more elevated toward the ends; the gunwale fixed on the outside is three inches thick; the sides, from the under part of the gunwale along the whole length of the regular sheer, extending twenty-one feet six inches, are cased with layers of cork, to the depth of 16 inches downward; and the thickness of this casing of cork being four inches, it projects at the top a little without the gunwale; the cork on the outside is secured with thin plates or slips of copper, and the boat is fastened with copper nails; the thwarts (or seats) are five in number, double banked, consequently the boat may be rowed with ten oars; the thwarts are firmly stanchioned; the side oars are short (A), with iron tholes, and rope grommets, so that the rower can pull either way. The boat is steered with an oar at each end; and the steering oar is one-third longer than the rowing oar; the platform placed at the bottom within the boat, is horizontal the length of the midships, and elevated at the ends, for the convenience of the steerman, to give him a greater power with the oar. The internal part of the boat next the sides, from the under part of the thwarts down to the platform, is cased with cork; the whole quantity of which, affixed to the life-boat, is nearly seven hundred weight; the cork indisputably contributes much to the buoyancy of the boat when full of water, is a good defence when going alongside a vessel, and is of principal use in keeping the boat in an crect position in the sea, or rather of giving her a very

lively and quick disposition to recover from any sudden Life-Boat cant or lurch which she may receive from the stroke of a heavy wave: but, exclusive of the cork, the admirable construction of this boat gives it a decided preeminence. The ends being similar, the boat can be rowed either way, and this peculiarity of form alleviates her in rising over the waves; the curvature of the keel and bottom facilitates her movement in turning, and contributes to the ease of the steerage, as a single stroke of the steering oar has an immediate effect, the boat moving as it were upon a centre; the fine entrance below is of use in dividing the waves, when rowing against them; and combined with the convexity of the bottom and the elliptical form of the stem, admits her to rise with wonderful buoyancy in a high sea, and to launch forward with rapidity, without shipping any water, when a common boat would be in danger of being filled. The flaunching or spreading form of the boat, from the floor heads to the gunwale, gives her a considerable bearing; and the continuation of the breadth well forward, is a great support to her in the sea and it has been found by experience that boats of this construction are the best sea boats for rowing against the turbulent waves. The internal shallowness of the boat from the gunwale down to the platform, the convexity of the form, and the bulk of cork within, leave a very diminished space for the water to occupy; so that the life-boat, when filled with water, contains a considerably less quantity than the common boat, and is in no danger either of sinking or overturning.

It may be presumed by some, that in cases of high wind, agitated sea, and broken waves, a boat of such a bulk could not prevail against them by the force of the oars; but the life-boat, from her peculiar form, may be rowed a-head, when the attempt in other boats would fail (B). Boats of the common form, adapted for speed, are of course put in motion with a small power; but for want of buoyancy and bearing, are overrun by the waves and sunk, when impelled against them and boats constructed for burthen, meet with too much resistance from the wind and sea, when opposed to them, and cannot in such cases be rowed from the shore to a ship in distress. An idea has been entertained that the superior advantages of the life-boat are to be ascribed solely to the quantity of cork affixed; but this is a very erroneous opinion, and I trust has been amply refuted by the preceding observations on the construction of this boat. It must be admitted that the application of cork to common boats would add to their buoyancy and security; and it might be a useful expedient, if there was a quantity of cork on board of ships, to prepare the boats with, in cases of shipwreck, as it might be expeditiously done in a temporary way, by means of clamps, or some other contrivance. The application of cork to some of the boats of his majesty's ships (the launches) might be worthy of consideration, more particularly, as an experiment might be made at a little expence, and without injury to the boats. "The life-boat is kept in a boat-house, and placed

upon

(A) The short oar is more manageable, in a high sea, than the long oar, and its stroke is more certain. (B) An extraordinary case might certainly happen, when a forcible combination of the wind, the waves, and

the tide, might render it impracticable to row the life-boat from the shore.

Lafe-Boat. upon four low wheels, ready to be moved at a moment's notice. These wheels are convenient in conveying the boat along the shore to the sea; but if she had to travel upon them, on a rough road, her frame would be exceedingly shaken; besides, it has been found difficult and troublesome to replace her upon these wheels, on her return from sea.

"Another plan has therefore been adopted: two wheels of 12 feet diameter, with a moveable arched axis, and a pole fixed thereto, for a lever, have been constructed. The boat is suspended, near her centre, between the wheels, under the axis; toward each extremity of which is an iron pin. When the pole is elevated perpendicularly, the upper part of the axis becomes depressed, and a pair of rope slings, which go round the boat, being fixed to the iron pins, she is raised with the greatest facility, by means of the pole, which is then fastened down to the stem of the boat."

Temporary LIFE-Boat,-an invention by the reverend Mr Bremner, minister of Walls and Flota in Orkney, by which any ordinary ship's boat may be converted into a life-boat, so that in cases of shipwreck, the crew may be saved by means of their own boats. Mr Bremner states, in describing his plan to the Highland Society of Scotland, that it had received the approbation of the Trinity houses of London and Leith, of the Royal Humane Society of London, and of many captains of merchantmen. An experiment was made in the port of Leith under the superintendence of Mr Bremner himself, and in presence of a committee of the directors of the society. This experiment proved satisfactory to the committee, whose favourable report to the directors induced them to present Mr Bremner with a piece of plate in testimony of their approbation of his scheme. The following is a general description of the method of preparing a boat for this purpose.

"The dimensions of the sloop's boat, with which the experiment was tried, were 14 feet in length, 5 feet 4 inches in width, and 2 feet 2 inches in depth. The only addition or previous preparation of the boat, was four ring bolts in the inside, and two auger bores or holes in the outside of the keel, as points of security for fixing the necessary seizing ropes (c). The ring bolts, within side the keel, were placed, the one forward, one-third from the stem, the other aft, one-third from the stern; the other two, the one directly at the stem, the other at the stern. The auger bores, outside the keel, being half way betwixt the rings, viz. the one betwixt the two rings forward, the other betwixt the two rings aft.

"Two empty hogsheads were then placed in the fore part of the boat, parallel and close to each other, and laid lengthways, fore and aft. These were secured in their places by passing the seizing ropes round all, that is, over the gunwales and through the auger bore in the keel, as alsó from the ring bolt in the stem to that next it in the keel, taking care in doing this, to pass the rope also through eyes on the slings of the casks, which have been previously prepared. The same process was observed in the after part of the boat. And

lastly, a bar of iron about three hundred weight, was Life-Boat. fixed to the keel, on the inside. A small quantity of cork was also placed in the stern, intended chiefly to raise to a proper height the casks placed above it, but without which the result of the experiment would have been the same.

"The quantity of cork necessary, which will depend on the size of the boat, is to be made up into several parcels, but none larger than one person can easily manage. Each parcel to be properly secured and num bered, so as that the whole may fit and fill up the boat completely, in the spaces betwixt the ring bolts, fore. and aft, as above described; and to answer the end, it is material that there should be cork enough to rise nearly three feet above the gunwales, so as to form an arch from gunwale to gunwale. The cork being thus laid in the boat, it is to be properly secured, first by passing a strong rope round all, over the gunwales, and through the auger bore, outside the keel; as also by passing seizing ropes from the ring bolt in the stem, to that next it in the keel, taking care to make as many turns and seizings betwixt these ring bolts, as completely to secure the cork from slipping out. The very same thing to be done as to the rope round the gunwales, and through the hole outside the keel, with seizing ropes from the ring bolts, to be made aft, or in the stern of the boat.

"Where cork cannot be had, or may not be kept in readiness on account of its expence, which, however, is not very great, casks will answer the purpose, though it may be doubtful whether there would not be a greater chance that the fury of the waves might unloose them, unless particular care was taken to have them properly fixed. In the case of casks, two empty ones are to be placed in the fore part of the boat, parallel to one another, close together, and to be laid lengthwise fore and aft. Two other empty casks to be placed in the same way in the stern, or aft part of the boat, and the whole to be secured as firmly and compactly as possible, by strong ropes round the boat and casks, and also by seizing ropes in the same way as described in the case of cork; then two other empty casks, of the same dimensions, one fore, and another aft, to be placed over and in the middle between the two already fixed, and to be firmly secured, as above-mentioned.

"As the boat is to be thus prepared on the deck of the ship, when danger appears, a piece of sail should be thrown in below, betwixt, and about the casks, for the more effectually securing them, and to prevent the seizing ropes from so readily slipping; it would be proper also to have slings on the casks, with eyes in them, through which to pass the seizing ropes.

66

Lastly, both in the case of cork and casks, an iron bar, of about three hundred weight, for such a boat as above described, should be secured to the keel on the inside, in the middle or empty space. This middle, or empty space of the boat, is for the sailors, and in a ship's boat of the common size may hold eight people, with room to work a pair of oars. Every thing being previously

(c) It is probable, that ring bolts fixed in the gunwales, might answer as well as passing the ropes round the bottom of the boat and through the auger bores in the keel.

Life-Boat previously ready, it is certain that the necessary fixing of the casks will not take up above ten or twelve miLigature. nutes, and it is obvious the cork can be fixed in a much shorter period. It is also completely ascertained, that a boat so prepared, though full of water, will not sink, but on the contrary be extremely buoyant, and will easily go a-head: That it would be next to impossible the boat should overset; but, in case of this at any time happening, she would instantly return to her proper position on her keel. Though the experiment was tried only with casks, with but a small quantity of cork, as before stated, yet it is generally believed, and Mr Bremner himself is of the same opinion, that it might answer equally well, and perhaps better, to have the cork or casks stowed in midships, leaving an empty space in each end, by which means the management of the boat by the helm or rudder would be preserved, though the other plan seems better, in the view of using

pars.

Vegetable LIFE. See PLANTS.

LIFE-Rent, in Scots Law. When the use and enjoy ment of a subject is given to a person during his life, it is said to belong to him in life-rent.

LIGAMENT, in its general sense, denotes, any thing that ties or binds one part to another.

LIGAMENT, in Anatomy, a strong compact substance, serving to join two bones together. See ANATOMY, N° 7.

LIGARIUS, QUINTUS, a Roman proconsul in Africa, 49 B. C. Taking part with Pompey, he was forbid by Julius Cæsar to return to Rome to obtain his pardon, Cicero made that admired oration in his defence, which has immortalized the memory of the client with that of his celebrated advocate.

LIGATURE, in Surgery, is a cord, band, or string; or the binding any part of the body with a cord, band, fillet, &c. whether of leather, linen, or any other matter.

Ligatures are used to extend or replace bones that are broken or dislocated; to tie the patients down in lithotomy and amputations; to tie upon the veins in phlebotomy, on the arteries in amputations, or in large wounds; to secure the splints that are applied to fractures; to tie up the processes of the peritoneum with the spermatic vessels in castration; and, lastly, in taking oil warts or other excrescences by ligature.

LIGATURE, is also used to signify a kind of bandage or fillet, tied round the neck, arm, leg, or other part of the bodies of men or beasts, to divert or drive off some disease, accident, &c.

LIGATURE, is also used for a state of impotency, in respect to venery, pretended to be caused by some charm or witchcraft.

Kempfer tells of an uncommon kind of ligature or knotting, in use among the people of Macassar, Java, Malacca, Siam, &c. By this charm or spell, a man binds up a woman, and a woman a man, so as to put it out of their power to have to do with other any son; the man being thereby rendered impotent to any other woman, and all other men impotent with respect to the woman.

per

Some of their philosophers pretend, that this ligature may be effected by the shutting of a lock, the drawing of a knot, or the sticking of a knife in the VOL. XIL. Part I..

wall, at the point of time wherein the priest is joining Ligature, a couple together; and that a ligature, thus effected, Light. may be dissolved, by the spouse's urining through a ring. This piece of superstition is said to obtain also among the Christians of the East.

The same author tells us, that during the ceremony of marriage in Russia, he observed an old fellow lurking bebind the church-door, and mumbling over a string of words; and, at the same time, cutting a long rod, which he held under his arm into pieces; which, it seems, is a common practice at the marriages of great persons, and done with design to elude and counterwork any other person that might possibly be inducing the ligature.

The secret of inducing a ligature is delivered by the same author, as he was taught it on the spot by one of their adepts: but it is too absurd and obscene to deserve being transcribed here.

M. Marshal mentions a ridiculous form of ligature, which he received from a bramin of Indostan: "If (says he) the little worm in the wood lukerara kara be cut into two, and the one part stirs and the other not, if the stirring part be bruised, and given with half a beetle to a man, and the other half to a woman, the charm will keep each from ever having to do with any other person. Phil. Trans. N° 268.

LIGATURE, in the Italian music, signifies a tying Hence syncopes are often called ligatures, because they are made by the ligature of many notes. There is another sort of ligatures for breves, when there are many of these on different lines, or on different spaces, to be sung to one syllable.

LIGATURES, among printers, are types consisting of two letters or characters joined together; as &, &, ff; , fi. The old editions of Greek authors are extremely full of ligatures; the ligatures of Stephens are by much the most beautiful.-Some editions have been lately printed without any ligatures at all; and there was a design to explode them quite out of printing. Had this succeeded, the finest ancient editions would in time have grown useless: and the reading of old manuscripts would have been rendered almost impracticable to the learned themselves.

LIGHT, in the most common acceptation of the word, signifies that invisible etherial matter which makes objects perceptible to our sense of seeing. Figuratively, it is also used for whatever conveys instruction to our minds, and likewise for that instruction itself.

For an account of the chemical properties of light, see CHEMISTRY Index; and for its physical properties, see OPTICS.

LIGHT independent of Heat. In general, a very considerable degree of heat is requisite to the emission of light from any body; but there are several exceptions to this, especially in light proceeding from pu trescent substances and phosphorus, together with that. of luminous animals, and other similar appearances. Light proceeding from putrescent animal and vegetable substances, as well as from glow-worms, is mentioned by Aristotle. Thomas Bartholin mentions four De luce kinds of luminous insects, two with wings, and two animal. without; but in hot climates travellers say they are P. 153. 206. found in much greater numbers, and of different speB +

cies,

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