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and suddenly contracting near the tail, which is short and slightly acuminate. A. dubius, which very nearly resembles the javanicus, except that the head is covered with very minute, rough, and warted scales, differing in size alone from those on the other part of the animal. The dubius measures only about three feet in length. A specimen is to be seen in the British Museum. Its native place is not ascertained. A. fasciatus, resembles the dubius so much, that some naturalists suppose them both to be of the same species, and differing only in age and cast of colours. The specimen in the British Museum is about eighteen inches long. See plate Serpentes, fig. 1. ACRONICHAL, or AchronycAl, in astronomy, an appellation given to the rising of a star above the horizon, at sunset; or to its setting, when the sun rises. Acro. nichal is one of the three poetical risings of a star; the other two being called cosmical and helical. This term is also applied to the superior planets Saturn, Jupiter, and Mars, when they are come to the meridian of midnight. ACROSTERMUM, in botany, a genus of the Cryptogamia Fungi class and order; fungus quite simple, nearly erect, emitting the seeds exteriorly from the top. There are four species. ACROSTICUM, rusty-back, wall-rue, or forked fern, in botany, a genus of the Cryptogamia Filices; the character of which is, that the fructifications cover the whole inferior surface of the leaf. There are 45 species distributed into different classes. Few of the species have been introduced into gardens. Those of Europe may be preserved in pots, filled with gravel and line-rubbish, or planted on walls, and artificial rocks; but most of them being natives of very hot climates, must be planted in pots, and plunged into the bark pit. ACTEA, in botany, a genus of plants of the Polyandria Monogynia class and order. Gen. character; calyx perianth, four-leaved; leaflets roundish, obtuse, concave, caducous; cor. petals four, accuminate to both ends, larger than the calyx; filaments about 30; germ superior ovate; no stile; stigma thickish, obliquely depressed; pericarp a berry, oval-globose, smooth, one-furrowed, one celled; seeds very many, semi-orbicular, lying over each other in two rows. There are four species, viz. the spicata; racemosa; japonica, and aspera; of the first there are varieties, as the black-berried herb Christopher, or bane-berry, found in the northern

parts of England; the Christopher with white berrries, a native of America; and that with red berries. The racemosa, or black snake-root, found also in America, of which the root is much used in many disor. ders, and is supposed to be an antidote against the bite of the rattle-snake. The leaves of the A. aspera, being extremely rough, the Chinese use them in polishmg their tin ware. ACTINIA, in natural history, a genus of the Mollusca order of worms; the characters of which are, body oblong, cylindrical, fleshy, contractile, fixed by the base; mouth terminal, expansile, surrounded with mumerous cirri, and without any aperture. There are 36 species. These marine animals are viviparous, and have no aperture but the mouth. They feed on shell-fish, and other marine animals, which they draw in with their feelers, in a short time rejecting through the same aperture the shells and indigestible parts. They assume various forms; and where the tentacula or feelers are all expanded, have the appearance of full-blown flowers. Many of them are eatable, and some of them very sapid. ACTINOLITE, in mineralogy, a family, comprehending six species, viz. the actinolite, smaragdite, tremolite, cyanite, saylite, and schalstone. The actinolite occurs chiefly in beds in primitive mountains, and is divided into three sub-species, viz. the asbestos, common, and glassy. The asbestos colours greenish grey, mountain green, smelt blue, olive green, yellowish, and liverbrown, Massive, and in capillary crystals. Soft; brittle; specific gravity 2.5 to 2.9. Melts before the blow-pipe. The usual colour of the common is leek green, but its specific gravity is between 3.0 and 3.3. The principal colour of the glassy is mountain green, passing to the emerald green. Specific gravity 2.9 to 3.9. ACTION, in mechanics and physics, is the pressure or percussion of one body against another. It is one of the laws of nature, that action and re-action are equal, that is, the resistance of the body moved is always equal to the force communicated to it; or, which is the same thing, the moving body loses as much of its force, as it communicates to the body moved. If a body be urged by equal and contrary actions or pressures, it will remain at rest. But if one of these pressures be greater than its opposite, motion will ensue toward the parts least pressed.

It is to be observed, that the actions of bodies on each other, in a space that is carried uniformly forward, are the same as if the space were at rest: and any powers or motions that act upon all bodies, so as to produce equal velocities in them in the same, or in parallel right lines, have no effect on their mutual actions, or relative motions. Thus the motion of bodies aboard a ship, that is carried steadily and uniformly forward, are performed in the same manner as if the ship was at rest. The motion of the earth round its axis has no effect on the actions of bodies and agents at its surface, but so far as it is not uniform and rectilineal. In general, the actions of bodies upon each other depend not on their absolute, but relatire motion. Action, in law, denotes either the right of demanding, in a legal manner, what is any man's due, or the process brought for the recovering the same. Actions are either criminal or civil. Criminal actions are to have judgment of death, as appeals of death, robbery, &c. or only judgment for damage to the injured party, fine to the king, and imprisonment. Under the head of criminal actions may likewise be ranked penal actions, which lie for some penalty or punishment on the party sued, whether it be corporal or pe. cuniary. Also actions upon the statute, brought on breach of any stutute, or act of parliament, by which an action is given that did not lie before; as where a person commits perjury to the prejudice of another, the injured party shall have an action upon the statute. And lastly, popular actions, so called, because any person may bring them on behalf of himself and the crown, by information, &c. for the breach of some penal statute. Civil actions are divided into real, personal, and mixed. Real action is that whereby a man claims a title, lands, tenements, &c. in fee, or for life, and this action is either possessory, or ancestral; possessory, where the lands are a person's own possession or seisin; ancestral, when they were of the possession or seisin of his ancestors. Personal action, is one brought by one man against another, upon any contract for money or goods, or on account of trespass, or other offence committed; and thereby the debt, goods, chattels, &c. claimed. Mixt action, one lying as well for the

thing demanded as against the person whe has it; and on which the thing is recovered with damages for the wrong sustained ; such is an action of waste, sued against a tenant for life, the place wasted being recoverable, with treble damages for the wrong done.

ACTS of parliament, statutes, acts, edicts, made by the king, with the advice and consent of the lords spiritual and temporal, and commons, in parliament assembled. An act of parliament is the highest possible authority, and hath power to bind not only every subject, but the king himself, if particularly named therein, and cannot be altered or repealed but by the same authority. Where the common law and the statute law differ; the common law gives place to the statute, and an old statute gives place to a new one. Penal statutes must be construed strictly; thus a statute of Edw. I, having enacted, that those convicted of stealing horses should not have the benefit of clergy, the judges conceived that this did not extend to him that should steal but one horse, and a new act for that purpose was passsd in the following year. Statutes against frauds are to be liberally and beneficially expounded. One part of a stutute must be construed by another, that the whole may, if possible, stand. A saving clause totally repugnant to the body of the act. If a statute that repeals another is itself repealed afterwards, the first statute is hereby revived. Acts of parliament derogatory from the power of subsequent parliaments bind not. Acts of parliament that are impossible to be performed are of no validity.

ACULEATE, or Aculeated, an appellation given to any thing that has aculei, or prickles: thus fishes are divided into those with aculeated and not aculeated fins.

The same term is applied, in botany, to the stems and branches of those plants that are furnished with prickles, as the rose, the raspberry, and barberry trees. The prickle

differs from the thorn, which is another spe

cies of armature, or defence, against animals, in being only a prolongation of the cortex or outer bark of the plant, and not connected with nor protruded from the wood. This is apparent from the ease with which such prickles are detached from the stem with the bark, while the other, and more rigid species of weapon, being an expansion of the ligneous body, cannot be detached without rendering and tearing the

substance of the wood. Prickles are either straight, as in the solanum indicum : or bent inwards, as in the mimosa cineraria; or bent outwards; or downy, that is, covered with a sort of wool. See ToMENTUM. ACUMINATE, in natural history, a term applied to fishes whose tails end in a sharp point. AD, a Latin preposition, expressing the relation of one thing to another. It is frequently prefixed to cther words: thus, Ad hominem, among logicians, an argument drawn from the professed belief or principles of those with whom we argue. An calorem, among the officers of the king's revenue, a term used for such duties, or customs, as are paid according to the value of the goods sworn to by the owner. ADAGIO, in music, signifies the second degree of music from slow to quick. It is applied to music not only meant to be performed in slow time, but also with grace and embellishment. ADAMANTINE spar, in mineralogy, one of the species of the ruby family, found only in China. Colour dark hair brown. Massive, crystallized in six-sided prisms, and six-sided pyramids, having their apex truncated. Specific gravity 3.98. See Ruby. ADAMBEA, in botany, a genus of the Polyandria Monogynia class and order, of which there is but a single species, which grows on the coast of Malabar, in sandy and stony places; rises to about seven feet, and sends forth branches which are terminated by panicles of fine purple flowers, large and resembling roses. ADANSONIA, in botany, a genus of the Monadelphia order, and Polyandria class, named after Michael Adanson, an indefatigable French naturalist. The A. digitata, Ethiopean sour-gourd, or monkies' bread, called also abavo, is the only species known of this genus. ADDER. See Coluber. ADDITION, in arithmetic, the first of the four fundamental rules of that art, whereby we find a sum equal to several smaller ones. See ALGEBRA and ARITH MEtic. Apnitions, in law, denote all manner of designations given to a man, over and above his proper name and surname, to shew of whatestate, degree, mystery, place of abode, &c. he is. Additions of degree are the same with titles of honour or dignity, as knight, lord, earl, duke, &c.

Additions of estate are yeoman, gentleman, esquire, and the like. Additions of mystery, or trade, are carpenter, mason, painter, engraver, and the like. Additions of place, or residence, are London, Edinburgh, Bristol, York, Glasgow, Aberdeen, &c. These additions were ordained to prevent one man's being grieved, or molested, for another; and that every person might be certainly known, so as to bear his own burden. If a man is of different degrees, as duke, earl, &c. he shall have the most worthy; and the title of knight, or baronet, is part of the party's name, and therefore ought to be rightly used; whereas that of esquire, or gentleman, being as people please to call them, may be used, or not, or varied at pleasure. A Peer of Ireland is no addition of honour here; nay, the law-addition to the children of British noblemen is only that of esquire, commonly called lord. Writs without the proper additions, if excepted to, shall abate; only where the process of outlawry doth not lie, additions are not necessary. The addition of a parish, not in any city, must mention the county, otherwise it is not good. Addition, in heraldry, something added to a coat of arms, as a mark of honour; and therefore directly opposite to abatement. ADDUCTOR, in anatomy, a general name for all such muscles as serve to draw one part of the body towards another. See ANAToMY. ADELIA, in botany, a genus of the Dioecia Gynandria class and order. Male: calyx three parted; no corolla; stamina numerous; united at the base. Female: calyx five parted; no corolla; styles three, lacerated. Capsule three-grained. ADENANTHERA, in botany, a genus of the Decandria Monogynia class of plants, the calyx of which is a single-leaved perian. thium, very small, and cut into five seg. ments: the corolla consists of five lanceolated bell-shaped petals; the fruit is a long membranaceous compressed pod, containing several round seeds. There are three species: A. paronina, which is one of the largest trees in the East Indies. Its duration is 200 years, and its timber is much used on account of its solidity: the powder of the leaves is used in their religious ceremonies; the seeds are eaten, and also valued as weights, being each of them four grains. This species must be raised on a hot-bed from seeds. It has never flowered in England: it is of very slow growth. The other species, viz. the A. falcata, and A. scandens, have not been cultivated in this country. ADENIA, in botany, a genus of the Hexandria Monogynia class and order, that grows in Arabia. There is but one species, which is mentioned by Forskal, in his Flor. AEgypt. He says that the powder of the young branches mixed in any kind of liquor is a strong poison, and that the capparis spinosa is an antidote to it. ADFECTED equations, in algebra, those wherein the unknown quantity is found in two or more different powers: such is a'— ar” + b x = a b. ADHESION, in philosophy and chemistry, is a term generally made use of to express the property which certain bodies have of attracting to themselves other bodies, or the force by which they adhere together: thus, water adheres to the finger, mercury to gold, &c. Hence arises an important distinction between two words, that in a loose and popular sense are often confounded. Adhesion denotes an union to a certain point between two dissimilar substances, and cohesion that which retains together the component particles of the same mass. See Cohesion. Adhesion may take place either between two solids, as two hemispheres of glass,which, according to an experiment of Desaguliers, adhere to each other with a force equal to 19 ounces on a surface of contact one-tenth of an inch in diameter; or between solids and fluids, as the suspension of water in capillary tubes; or lastly, between two fluids, as oil and water. About the same time Mr. Hauksbee proved experimentally the error which Bernoulli had fallen into, in attributing the adhesion of surfaces and capillary attraction to the pressure of the atmosphere. Nevertheless, in 1772, M. M. Lagrange and Cigna, taking for granted a natural repulsion between water and oily substances, imagined, if there was an adhesion between water and oil, or tallow, that it must be occasioned by a cause different from attraction: and having ascertained the reality of the adhesion, they concluded that it was occasioned by the pressure of the air, and that Dr. Taylor's method was not well founded. Such was the state of opinions on the subject, when, in 1773, Guyton Morveau made

his celebrated experiments on adhesion, in presence of the Dijon Academy, demonstrating, as indeed Hauksbee had done before him, not only that water ascends between two parallel plates of tallow, separated from each other of a line, but also that the atmospheric pressure is not in the least degree the cause of the phenomenon, which is solely attributable to attraction: in proof of this, a polished disk of glass, 30 lines in diameter, was suspended to the arm of a balance, and brought into contact with a surface of mercury; the counterpoise required to separate it was equivalent to 9 gros and a few grains, and upon moving the apparatus into the receiver of an air-pump, and forming as perfect a vacuum as possible, precisely the same counterpoise was required as before. In the prosecution of his inquiries on this subject, he observed, that the same disk of glass, which, when in contact with pure

water, adhered to it with a force equal to

258 grains, required a counterpoise of only 210, in order to separate it from a solution of potash, notwithstanding the superior density of this last. This inequality of effects on equal diameters, and in an inverse order to that of the respective specific gravities of the two fluids, appeared not only to be decisive in favour of Dr. Taylor's method, but to encourage the hope of applying it to the calculation of chemical affinities. In order to verify this proposition, plates of the different metals in their highest stäte of purity were procured, perfectly round, an inch in diameter, of the same thickness, well polished, and furnished with a small ring in the centre of each, so as to keep them suspended precisely parallel to the plane of the horizon. Each of these plates was in turn suspended to the arm of an assay balance, and exactly counterpoised by weights placed in the scale attached to the opposite arm; the plate, thus balanced, was applied to the surface of some mercury in a cup, about two lines beneath it, by sliding the plate over the

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