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I speak too long; but 't is to piece the time,
To eke it, and to draw it out in length,
To stay you from election.

Id. Merchant of Venice.
Now, if 'tis chiefly in the heart,
That courage does itself exert,
"Twill be prodigious hard to prove,

That this is eke the throne of love. Prior. Your ornaments hung all, On some patched doghole eked with ends of wall. Pope. EKRON, a city and government of the Philistines. It fell by lot to the tribe of Judah, in the first division made by Joshua (xv. 45.) but was afterwards given to the tribe of Dan, (xix. 43.) It was situated near the Mediterranean, between Ashdod and Jamnia. Ekron was a powerful city, and it does not appear that the Jews were ever sole peaceable possessors of it: the Ekronites were the first who said that it was necessary to send back the ark of the God of Israel, in order to be delivered from those calamities which the presence of it brought upon their country. 1 Sam. v. 10. The idol Baalzebub was principally adored at Ekron. 2 Kings i. 2. &c.

ELA'BORATE, v. a. & adj.

ELA BORATELY, adv.
ELA BORATENESS, n. s.
ELABORA'TION.

e, out, and laboro, to labor. To
prove by labor: as an adjective,
riously finished or performed.

Spanish and Port. elaborar ; Ital. and Lat. elaborare, from produce or imhighly or labo

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ELEAGNUS, the oleaster, or wild olive, a genus of the monogynia order, and tetrandria class of plants; natural order sixteenth, calyciflore: COR. none: CAL. campanulated, quadrifid, superior: FRUIT a plum below the campanulated calyx This genus must not be confounded with the oleaster or wild olive of Gerard, Parkinson, and Ray which is only a particular species of olive, called by Tournefort and Casper Bauhine, olea sylves tris. See OLEA. There are ten species.

1. E. inermis, without thorns, is the kind commonly preserved in the gardens of this country. The leaves are more than three inches long, and half an inch broad, and have a shining appearance like satin. The flowers come out at the foot-stalks of the leaves, sometimes singly, at other times two, and sometimes three, at the same place. The outside of the empalement is silvery and studded; the inside of a pale yellow. It has a very strong scent. The flowers appear in July, and are sometimes succeeded by fruit.

2. E. latifolia, with oval leaves, is a native of Ceylon, and some other parts of India. In this country it rises with a woody stem to eight or nine feet, dividing into many crooked branches, garnished with oval and silvery leaves, which have several irregular spots of a dark color on the surface. They are placed alternately on the branches, and continue all the

year.

3. E. spinosa, the eastern broad-leaved olive with a large fruit, is a native of the Levant and some parts of Germany. The leaves are about two inches long, and one and a half broad in the middle. They are placed alternate, and are of a silver color: at the foot-stalk of every leaf there comes out a pretty long sharp thorn, which are alternately longer: the flowers are small, the inside of the empalement is yellow, and they have a strong scent when fully open.

The first and last species may be propagated by laying down the young shoots in autumn. They will take root in one year; when they may be cut off from the old trees, and either transplanted into a nursery for two or three years, or into places where they are to remain. The proper time is in the beginning of March, or early in autumn. They should be screened from high winds; for they grow very freely, and are apt to be split by the wind, if too much exposed. The latifolia is too tender to endure the open air of this country; and therefore must be kept in a warm stove, except during a short time in the warmest part of summer. From the flower of these plants an aromatic and cordial water has been drawn, which is said to have been successfully used in putrid and pestilential fevers.

ELEOCARPUS, in botany, a genus of the monogynia order, and polyandria class of plants: COR. pentapetalous and lacerated: CAL. pentaphyllous: FRUIT a plum with a wrinkled kernel. Species five, natives of India and New

Zealand.

ELÆOMELI, in ancient medicine, a sweet oil, as thick as honey, said to flow from a tree in Syria, and to have been useful in bilious complaints.

ELÆOTHESIUM, in antiquity, the anointing room, or place where those who were to

wrestle or had bathed, anointed themselves. See GYMNASIUM.

ELAH, the son of Baasha, the fourth king of Israel after the separation of the ten tribes from Judah. He was murdered while in a state of intoxication, by Zimri, when he had reigned only two years, A. M. 3014, and A.A.C. 934.

ELAH, in ancient geography, a valley of Israel, famous for the defeat and death of Goliath, the Philistine, by David.

ELAM, in ancient geography, a country frequently mentioned in Scripture, lying south-east of Shinar. In the time of Daniel, (viii. 2.) Susiana seems to have been part of it; and, before the captivity, it does not appear that the Jews called Persia by any other name. Elymæ and Elymais are often mentioned by the ancients. Ptolemy, though he makes Elymais a province of Media, places Elymæ in Susiana, near the sea coast. Stephanus takes it to be a part of Assyria; but Pliny and Josephus more properly of Persia, whose inhabitants, the latter tells us, sprang from the Elamites. The best commentators agree, that the Elamites, who were the ancestors of the Persians, were descended from Elam, the son of Shem. It is likewise allowed, that the inspired writers constantly intend Persia, when they speak of Elam and the kingdom of Elam. ÉLANCE, v. a. Fr. elancer. To throw out; to dart; to cast as a dart.

While thy unerring hand elanced
Another, and another dart, the people
Joyfully repeated Jo!

Prior.

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ELAPHEBOLIA, from λapoç, a deer; in Grecian antiquity, a festival in honor of Diana the huntress. In the celebration a cake was made in the form of a deer, and offered to the goddess. It owed its institution to the following

circumstance:-When the Phocians had been severely beaten by the Thessalians, they resolved, by the persuasion of one Deiphantus, to raise a pile of combustible materials, and burn their wives, children, and effects, rather than submit to the enemy. This resolution was unanimously approved by the women, who decreed Deiphantus a crown for his magnanimity. When every thing was prepared, before they fired the pile, they engaged their enemies, and fought with such desperate fury, that they totally routed them, and obtained a complete victory. In commemoration of this unexpected success, this festival was instituted to Diana, and kept with great solemnity.

ELAPHEBOLIUM, in Grecian antiquity, the ninth month of the Athenian year, answering to the latter part of February and beginning of March. It consisted of thirty days, and took its name from the elaphebolia which was celebrated

in it.

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morass over the other, differing indeed principally in its age, and perhaps as the timber might be different in the proportions of its component parts. Darwin.

Though years

Elapse, and others share as dark a doom,
They but augment the deep and sweeping thoughts
Which overpower all others, and conduct
The world at last to freedom!

Byron. ELASMIS, in natural history, a genus of talcs, composed of small plates in form of spangles, and either single, and not farther fissile, or, if complex, only fissile to a certain degree, and that in somewhat thick lamina. Of these talcs there are several varieties, some with large and others with small spangles, which differ also in color and other peculiarities.

ELA'STIC, adj. Fr. elastique, from Gr. ELASTICAL, ελασης, of the verb ελαω ; ELASTICITY, n. s.) Heb. g, to impel or cast off. Springy; energetic. The force whereby bodies restore themselves to a position from which they have been displaced.

By what elastick engines did she rear
The starry roof and roll the orbs in air.
Blackmore.

If the body is compact, and bends or yields inward to pression, without any sliding of its parts, it is hard from the mutual attraction of its parts. and elastick, returning to its figure with,a force rising Newton's Opticks.

The most common diversities of human constitutions arise from the solids, as to their different degrees of strength and tension; in some being too lax and weak, in others too elastick and strong.

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Me emptiness and dulness could inspire,
And were my elasticity and fire.
His form robust and of elastic tone,
Proportioned well, half muscle and half bone,
Supplies with warm activity and force

A mind well lodged, and masculine of course.
Cowper.

We can have no idea of a natural power, which could project a sun out of chaos, except by comparing

it

to the explosions or earthquakes owing to the sudden

evolution of aqueous or of other more elastic vapours; of the power of which, under immeasurable degrees of heat and compression, we are yet ignorant. Darwin. ELASTIC GUM, or ELASTIC RESIN. See GUM, ELASTIC.

ELASTIC VAPORS are such as may, by any external mechanical force, be compressed into a smaller space than they originally occupied ; restoring themselves, when the pressure is taken off, to their former state, with a force exactly first compressed. Of this kind are all the aerial proportioned to that with which they were at fluids, without exception, and all kinds of fumes raised by heat, whether from solid or fluid bodies. Of these some retain their elasticity only when a considerable degree of heat is applied to them, or to the substances which produce them; while

others remain elastic in every degree of cold, either natural or artificial, that has been observed. Of the former kind are the vapors of water, spirit of wine, mercury, sal ammoniac, and all kinds of sublimable salts; of the latter, those of spirit of salt, mixtures of vitriolic acid and iron, nitrous acid, and various metals; and, in short, the different species of aerial fluids indiscriminately. The elastic force with which any one of these fluids is endowed, has not yet been calculated, being ultimately greater than any obstacle we can put in its way. Thus, if we compress the atmospherical air, we shall find that, for some little time, it will easily yield to the force we apply; but every succeeding moment the resistance will become stronger, and a greater and greater force must be applied in order to compress it farther. As the compression goes on, the vessel containing the air becomes hot; but no power whatever has yet been able to destroy the elasticity of the continued fluid in any degree; for, upon removing the pressure, it is always found to occupy the very same space that it did before. The case is the same with aqueous steam, to which a sufficient heat is applied to keep it from condensing into water. This will yield to a certain degree; but every moment the resistance becomes greater, until at last it will overcome any obstacles whatever. An example of the power of this kind of steam we have every day in the steam engine; and the vapors of other matters, both solid and fluid, have frequently manifested themselves to be endowed with an equal force. Thus the force of the vapors of spirit of wine has occasioned terrible accidents when the worm has been stopped, and the head of the still absurdly tied down to prevent an explosion; the vapors of mercury have burst an iron box; and those of sal ammoniac, volatile salts, nitrous acid, marine acid, phosphorus, &c., have all been known to burst the chemical vessels which confined them, in such a manner as to endanger those who stood near them. In short, from innumerable observations, it may be laid down as an undoubted fact, that there is no substance whatever capable of being reduced into a state of vapor, but what in that state is endowed with an elastic force ultimately superior to any obstacle we can throw in its way. It has been a desideratum among philosophers to give a satisfactory reason for this astonishing power of elasticity in vapor, which is seemingly so little capable of accomplishing any great purpose when in an unconfined state. As air is that fluid in which, from the many experiments made upon it by the air-pump and otherwise, the elastic property has most frequently been observed, the researches of philosophers were at first principally directed towards it. The causes they assigned, however, were very inadequate; being founded upon. an hypothesis concerning the form of the particles of the atmosphere itself, which they supposed to be either rolled up like the springs of watches, or that they consist of a kind of elastic flakes. This was followed by another hypothesis concerning their substance, which was imagined to be per fectly elastic, and so strong that it could not be broken by any mechanical power whatever;

and thus they thought the phenomenon of the elasticity of the air might be explained. But an insuperable difficulty still attended their scheme, notwithstanding both these suppositions; for it was observed, that the elastic power of the air was augmented, not only in proportion to the quantity of pressure it was made to endure, but in proportion to the degree of heat applied to it at the time. Sir Isaac Newton was aware of this difficulty; and justly concluded that the phenomena of the air's elasticity could not be solved on any other supposition, than that of a repulsive power diffused all around each of its particles, which became stronger as they approached, and weaker as they removed from each other. Hence, the common phenomena of the air-pump and condensing-engine received a satisfactory explanation; but still it remained to account for the power shown in the present case by heat, as it could not be denied that this element had a very great share in augmenting the elasticity of the atmosphere, and seemed to be the only cause of elasticity in other vapors. It does not appear that Sir Isaac entered into this question, but contented himself with attributing to heat the property of increasing repulsion, and ascribing this to another unexplored property called rarefaction. Thus matters stood till the great discovery made by Dr. Black, that some bodies have the power of absorbing in an unknown manner the element in question, and parting with it afterwards, so that it flows out of the body which had absorbed it, with the very same properties that it had before absorption. Hence, many phenomena of heat, vapor, and evaporation, were explained in a manner much more satisfactory than had ever been attempted, or even expected before. One of these was that remarkable property of metals becoming hot by hammering; during which operation, in the doctor's opinion, the element of heat is squeezed out from between the particles of the metal, as water is from the pores of a sponge by pressing it between the fingers. Of the same nature is the phenomenon above-mentioned, that air when violently compressed becomes hot, by reason of the quantity of more subtile element squeezed out from among the particles. In this manner it appears, that heat and the repulsive power of Sir Isaac Newton are the very same; that by diminishing the heat of any quantity of air, its elasticity is effectually diminished, and it will of itself shrink into a smaller space as effectually as by mechanical pressure. In one case we have what may be called ocular demonstration of the truth of this doctrine, viz. that by throwing the focus of a strong burning lens upon a small quantity of charcoal in vacuo, the whole will be converted into inflammable air, having even a greater power of elasticity than common air in an equal degree of heat. Here there is nothing else but heat or light to produce the elastic power, or cause the particles of charcoal, which before attracted, now to repel each other. In another case we have evidence equally strong, that the element of heat by itself, without the presence of that of light, is capable of producing the same effect. Thus when a phial of ether is put into the receiver of an air-pump, and sur

rounded by a small vessel of water, the ether boils violently, and is dissipated in vapor, while the water freezes, and is cooled to a great degree. The dissipation of this vapor shows that it has an elastic force; and the absorption of the heat from the water shows, that this element not only produces the elasticity, but actually enters into the substance of the vapor itself; so that we have not the least reason to conclude that there is any other repulsive power by which the particles are kept at a distance from one another, than the substance of the heat itself. In what manner it acts, we cannot pretend exactly to explain, without making hypotheses concerning the form of the minute particles of matter, which must always be very uncertain. All known phenomena, however, concur in rendering the theory now laid down extremely probable. The elasticity of the steam of water is exactly proportioned to the degree of heat which flows into it from without; and, if this be kept up to a sufficient degree, there is no mechanical pressure which can reduce it into the state of water. This, however, may very easily be done by abstracting a certain portion of the latent heat it contains: when the elastic vapor will become a dense and heavy fluid. The same thing may be done in various ways with the permanently elastic fluids. Thus the purest dephlogisticated air, when made to part with its latent heat, by burning with iron, is converted into a gravitating substance of an unknown nature, which adheres strongly to the metal. If the decomposition is performed by inflammable air, both together unite into a heavy, aqueous, or acid fluid; if by mixture with nitrous air, still the heat is discernible, though less violent than in the two former cases. The decomposition indeed is slower, but equally complete, and the dephlogisticated air becomes part of the nitrous acid, from which it may be again expelled by proper means: but of these means heat must always be one; for thus only the elasticity can be restored, and the air be recovered in its proper state. The same thing takes place in fixed air, and all other permanently elastic fluids capable of being absorbed by others. The conclusion therefore, which we can only draw from what data we have, concerning the composition of elastic vapors, is, that all of them are formed of a terrestrial substance, united with the element of heat in such a manner, that part of the latter may be squeezed out from among the terrestrial particles; but in such a manner, that, as soon as the pressure is taken off, the surrounding fluid rushes in, and expands them to their original bulk: and this expansion or tendency to it will be increased in proportion to the degree of heat, just as the expansion of a sponge would be exceedingly augmented, if we could contrive to convey a stream of water into the heart of it, and make the liquid flow out with violence through every pore in the circumference. In this case, it is evident that the water would act as a power of repulsion among the particles of the sponge, as well as the fire does among the particles of the water, charcoal, or whatever other substance is employed. Thus far we may reason from analogy, but in all probability the internal and essential texture of these vapors will for ever remain unknown. It has been ima

gined by some, that the artificial elastic fluids have not the same mechanical property with common air, viz. that of occupying a space inversely proportional to the weights with which they are pressed: but this is found to be a mistake. All of them likewise have been found to be non-conductors of electricity, though probably not all in the same degree. See AIR and ELECTRICITY.

ELASTICITY. The cause or principle of elasticity, or springiness, is variously assigned. The Cartesians account for it from the materia subtilis making an effort to pass through pores that are too narrow for it. Other philosophers, in lieu of the subtile matter, substitute ether, or a fine etherial medium that pervades all bodies. Others, setting aside the precarious notion of a materia subtilis, account for elasticity from the great law of attraction, or the cause of the cohesion of the parts of solid and firm bodies. Thus, say they, when a hard body is struck or bent, so that the component parts are moved a little from each other, but not quite disjointed or broken off, or separated so far as to be out of the power of that attracting force whereby they cohere; they must certainly, on the cessation of the external violence, spring back to their former natural state. Elasticity has also been resolved into the pressure of the atmosphere: for a violent tension, or compression, though not so great as to separate the constituent particles of bodies far enough to let in any foreign matter, must yet occasion many little vacuola between the separated surfaces; so that upon the removal of the force they will close again by the pressure of the aerial fluid upon the external parts. See ATMOSPHERE. Lastly, others attribute the elasticity of all hard bodies to the power of resilition in the air included within them: and so make the elastic force of the air the principle of elasticity in all other bodies. These are clearly the mere conjectures of philosophy.

M. Libes, the author of the Nouveau Dictionnaire de Physique, has in that work given a new explication of the phenomena of elasticity, which depends upon the following principles

1. The signs of elasticity suppose a compres→ sion effected, that is, an alteration in the figure of Lodies produced by the mutual approach of the molecule: whence it results, that bodies, whose molecule yield with a very great facility to the slightest pressure, so as to roll one over another without changing their figure, cannot give sensible signs of elasticity. Such in general are liquids. 2. When an elastic body is compressed, some of its integrant molecule are brought nearer to one another, while others undergo a farther separation nearly equal to the approach of the former. 3. At the haitual degree of heat and pressure which we experience, all bodies have a volume determined by the ratio of equality, which exists between the attractive force of their particles, and the repulsive force communicated by the caloric combined with those particles.

These being granted, the re-establishment of solid bodies, after the compression, appears to be the result of the combined action of the caloric and of attraction. For in the molecule brought nearer by the compression, the repulsive force augments. and the attractive force likewise aug

ments; but the augmentation of the former force exceeds that of the latter. For, at the epoch of the formation of the body, such as it existed previous to the compression, the repulsive force communicated to its molecule by the caloric, was sufficient to give the degree of separation that was peculiar to the body: it was, therefore, superior to the attractive force until the moment when the moleculæ had become so far separated as was consistent with the natural state of the body. Whence it results, that if the particles are brought nearer together by compression, that is, if they are contracted with the caloric into a smaller space, the ratio of equality which subsisted between the attraction and the repulsion before the compression, must be destroyed in favor of the repulsion; and consequently, on the cessation of the compression, this surplus of repulsive force will act so as to separate again the moleculæ brought nearer by the compression, until the equilibrium is re-established between the attraction and the repulsion: and this equilibrium can only be re-established, when the molecules have recovered the degree of separation which they had previous to the compression. For similar reasons the attraction will predominate over the repulsion in those particles which have suffered a farther separation than is due to the natural state: it must, therefore, act to draw the particles nearer, and re-establish the equilibrium of those forces: and this equilibrium cannot be re-established until the molecules have recovered the relative distance which they had before the compression.

This theory M. Libes applies to an elastic sphere, as an ivory ball when falling upon a plane, to a plate of steel, whose extremities are brought towards each other by bending, and to the known effects of tempered metals, &c. In explaining the elasticity of aeriform fluids, M. Libes calls in to his aid a new force. For, in this kind of substances, the repulsion having prevailed over the attraction, their particles are retained in their mutual_position by the pressure of the atmosphere. But this force, it may be observed, being constant, makes no change in the results 'ust stated; except that, if the pressure be taken away, the particles of the gas will be separated from one another, until their relative distance attains a point determined by the equality between the attraction of the earth and the repulsion of those particles. Now, since all bodies contain caloric, it may be asked how it happens that all bodies are not elastic, if caloric be the principle of elasticity?

To this M. Lihes replies by the following remarks:-1st. Since there is not in nature any body, either perfectly hard, or perfectly soft, there is none but what possesses some degree of elasticity. 2dly. Perceptible signs of elasticity suppose the compression effected: it is not there

fore surprising, that bodies in which we cannot produce compression should not give any sign of elasticity. 3dly. Although caloric be the principle of elasticity, it does not follow that all bodies which contain caloric must exhibit this property, 1. Too much or too little caloric may equally weaken the elastic force. The different forms which distinguish the integrant molecule of disferent bodies; the different arrangement assumed by those moleculæ, according to circumstances, may be sometimes more or less favorable, at others more or less prejudicial to elasticity. 2. Soft bodies, such as butter, humid clay, &c., experience in their soft state a commencement of solution by water, which must alter the repulsive force of their moleculæ, and consequently hurt the elasticity. This is so true, that these bodies, freed from their aqueous parts, without changing their temperature, yield sensible signs of elasticity.

M. Libes, instead of attempting to explain, as some would expect, why caloric is elastic, says it is not necessary to suppose it so. For it may communicate this property to other bodies without being so itself. This position he illustrates as follows: when dry bread is immersed in water, that bread becomes swoln, its particles being farther separated from one another: water, therefore, by penetrating the pores of the bread, communicates to its particles a repulsive force; yet it would be ridiculous to conclude from hence, that the molecule of water mutually repel one another. In like manner, when we subject a body to the action of heat, its integrant molecules are separated from one another, and acquire a repulsive force by their combination with caloric: but this phenomenon, like the preceding, depends probably upon the concourse of several attractive forces, such as that of the molecule of the caloric, that of the particles of the body for one another, and, lastly, the reciprocal attraction of the particles of the caloric and those of the body penetrated by that fluid: whence it results that the elasticity of bodies by no means presupposes that of the caloric which has given rise to it. Indeed, M. Libes does not regard as completely demonstrated the existence of the fluid called caloric; he assumes the hypothesis as a matter of convenience, which enables us to abridge the language of philosophical discussions, and to found upon our reasonings an analytical calculus. He next, therefore, proceeds to state his theory analytically; and deduces from his formula the following results among others. 1. That when we compress elastic fluids, the repulsive force becomes more powerful than the attractive, and consequently when the compression ceases, the moleculæ ought to return towards their first position. 2. That liquids and aeriform fluids have the exclusive privilege of assuming a larger volume when the pressure of the atmosphere is taken away. Dict. de Phys. Retrospect, No. 8.

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