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It is found in Transylvania: it melts before the blow-pipe: the sulphur and syl

van are soon volatilized, and a blackish brown globule remains, which being melted with borax, a sort of silvery gold grain appears. It dissolves with effervescence in acids, and the nitro-muriatic acid extracts the gold from it.

SYMPHONIA, in botany, a genus of the Monadelphia Pentandria class and order.

Essential character: one styled; corolla globular; berry five-celled. There is only one species, viz. S. globulifera, a native of Surinam.

SYMPHYTUM, in botany, comfrey, a genus of the Pentandria Monogynia class and order. Natural order of Asperifoliæ, Borraginæ, Jussieu. Essential character; corolla tubular, ventricose; throat closed by lanceolate rays. There are three species. We shall notice the S. officinale, common comfrey: this plant has a perennial fleshy root, externally black; stem two or three feet high, upright, leafy, winged, branched at the top, clothed with short, bristly hairs, which point downward; leaves weaved, pointed, veiny, rough; the radical leaves on footstalks, broader than the rest; clusters of

flowers, in pairs, on a common foot-stalk, with an odd flower between them; corolla yellowish white, sometimes purple ; the rays downy at each edge. It is a native of Europe and Siberia; it is frequent in watery places, on the banks of rivers and ditches; flowering from the end of May to September.

SYMPLOCOS, in botany, a genus of the Polyadelphia Polyandria class and order. Natural order of Guaiacanæ, Jussieu. Essential character: calyx five-cleft; corolla five-petalled, erect at the base; stamens in four rows, growing to the tube of the corolla; fruit five-celled. There are four species.

SYNDIC, in government and commerce, an officer in divers countries, entrusted with the affairs of a city, or other community, who calls meetings, makes representations and solicitations to the ministry, magistracy, &c. according to the exigency of the case. The syndic is appointed to answer and account for the conduct of the body; he makes and receives proposals for the advantage thereof, controls and corrects the failings of particular persons of the body, or at least procures their correction at a public meeting. In effect, the syndic is at the same time both the agent and censor of the community.

SYNECDOCHE, in rhetoric, a kind of

figure, or rather trope, frequent among orators and poets. There are three kinds of synecdoches; by the fisrt, a part is taken for the whole, as the point for the sword, the roof for the house, the sails for the ship, &c. By the second, the whole is used for a part. By the third, the matter whereof the thing is made is used for the thing itself; as steel for sword, silver for money, &c. To which may be added another kind, when the species is used for the genus; or the genus for the species.

SYNGENESIA, in botany, the name of the nineteenth class in Linnæus's system, consisting of plants, in which the anthers, or male organs of generation, are united into a cylinder, the filaments on which they are supported, being separate and distinct: this class contains the numerous tribe of compound flowers. The orders of this class arise from the different modes of intercommunication of the florets, or lesser partial flowers,contained within the common calyx, This intercommunication admits of the four following cases. 1. When the florets are all hermaphrodite. 2. When they are hermaphrodites and females. 3. When they are her

maphrodites and florets of no sex: and 4. When they are males and females.

SYNGNATHUS, the pipe-fish, a genus of fishes of the order Cartilaginei. Generic character: snout nearly cylindrical; mouth terminal, without teeth or tongue, and furnished with a lid; body lengthened, jointed, and mailed with many-sided scales; no ventral fins. These fishes frequent the coast of the sea, and subsist upon worms and insects, and the ova of fishes. There are eight speeies, of which we shall notice the following:

S. acus, or the great pipe-fish, sometimes attains the length even of three feet, but is generally only fourteen inches long, extremely slender, and tapering towards the extremity. Its ova are found lying, in spring, in a longitudinal channel at the bottom of the abdomen, and the young are produced from this groove, completely formed. It is found in the seas of Europe.

The S. hippocampus, or sea-horse pipefish, inhabits the shores of the European and Indian seas, and is about ten inches long. When the head is bent downwards, it has a very considerable resemblance to that of a horse.

S. foliatus, or the foliated pipe-fish, is the most singular species of the genus, and this singularity consists chiefly in its possessing appendages, situated on very strong and rough spines, on the back, tail, and abdomen, of the shape of leaves, and which might easily be supposed, by a cursory observer, the real leaves of some of the fuci tribe. In the one presented to Sir Joseph Banks, and engraved in Shaw's Zoology, there are fourteen of these curious processes.

This animal

presents one of the most extraordinary objects exhibited by nature in the inmense variety of her living productions. See Pisces, Plate VI. fig. 3.

SYNOD, in astronomy, a conjunction or concourse of two or more stars, or planets, in the same optical place of the hea

vens.

SYNODENDRON, in natural history, a genus of insects of the order Coleoptera; antennæ clavate; the club lamellate; thorax gibbous, muricate or unequal; tip filiform, horny, palpigerous at the tip. There are four species.

SYNODICAL, something belonging to a synod: thus, synodical epistles, are circular letters written by the synods to the absent prelates and churches, or even those general ones directed to all the faithful, to inform them of what had paas

ed in the synod. For the synodical month, see the article MONTH.

SYNOVIA, the name given to a liquid secreted within the capsular ligaments of the joints, to facilitate motion by lubricating these parts. The synovia of the ox is a viscid, semi-transparent fluid, of a greenish white colour, which soon acquires the consistence of jelly, and not long after becomes again fluid, depositing a filamentous matter. Synovia mixes with water, and renders it viscid. When this mixture is boiled, it becomes milky, and some pellicles are deposited on the sides of the vessel. Alcohol produces a precipitate when added to synovia. This precipitate is albumen. After this matter is separated, the liquid still remains viscid; but if acetic acid be added, the viscidity disappears, and it becomes transparent, depositing a white filamentous substance, which resembles vegetable gluten. It is soluble in cold water, and in concentrated acids and pure alkalies. This fibrous matter is precipitated by acids and alcohol in flakes. The concentrated mineral acids produce a flaky precipitate, which is soon re-dissolved; but the viscidity of the liquid is not destroyed till they are so much diluted with water, that the acid taste is only perceptible. When synovia is exposed to dry air, it evaporates, and cubic crystals remain in the residuum, with a white saline efflorescence. first are muriate of soda, and the latter carbonate of soda. This substance soon becomes putrid, giving out ammonia during its decomposition. By distillation in a retort, it yields water, which soon becomes putrid; water containing a portion of ammonia, and an empyreumatic oil, with carbonate of ammonia: by washing the residuum, muriate and carbonate of soda may be obtained. A small portion of phosphate of lime is found in the coaly matter. The constituent parts of synovia are the following:

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SYNTAX, in grammar, the proper construction, or due disposition of the words of a language, into sentences, or phrases; or the manner of constructing one word

with another, with regard to the different terminations thereof, prescribed by the rules of grammar. Hence the office of syntax is, to consider the natural suitableness of words with respect to one another, in order to make them agree in gender, number, person, mood, &c. To offend in any of these points is called, to offend against syntax; and such kind of offence, when gross, is called a solecism, and when more slight, a barbarism. Syntax is generally divided into two parts, viz. concord, wherein the sounds are to agree in gender, number, case, and person; and regimen, or government, wherein one word governs another, and occasions some variations therein.

SYNTHESIS, the putting of several things together, as making a compound medicine of several simple ingredients,

&c.

SYNTHESIS, in logic, denotes a branch of method opposite to analysis, called the synthetic method.

SYRINGA, in botany, lilac, a genus of the Diandria Monogynia class and order. Natural order of Sepiariæ. Jasmineæ, Jussieu. Essential character: corolla fourcleft; capsule two-celled. There are four species, with several varieties. The S. vulgaris, common lilac, is a shrub growing to the height of eighteen or twenty feet, dividing into many branches; those of the white sort grow more erect than the blue; and the purple, or Scotch lilac, has its branches yet more diffused. The lilac is very common in the English gardens, where it has been long cultivated as a flowering shrub. It is supposed to grow naturally in some parts of Persia ; but is so hardy as to resist the greatest cold of this country.

SYRINGE, an instrument serving to imbibe or suck in a quantity of any fluid, and to squirt or expel the same with violence.

SYRUP. See PHARMACY.

SYSTEM, in general, denotes an assemblage or chain of principles and conclusions, or the whole of any doctrine, the several parts whereof are bound together, and follow or depend on each other; in which sense we may say, a system of philosophy, a system of divinity, &c.

SYSTEM, in astronomy, denotes an hypothesis or supposition of an arrangement of the several parts of the universe, whereby astronomers explain all the phenomena or appearances of the heavenly bodies, their motions, changes, &c. This is more properly called the systems of the world.

System and hypothesis have much the same signification, unless perhaps hypothesis be a more particular system, and system a more general hypothesis. The three most celebrated systems of the world are, the Copernican, the Ptolemaic, and Tychonic.

SYSTOLE, in anatomy, the contraction of the heart, whereby the blood is drawn out of its ventricles into the arteries; the opposite state to which is called the diastole, or dilatation of the heart.

SYZYGY, in astronomy, a term equally used for the conjunction and opposition of a planet with the sun. On the phenomena and circumstances of the syzygies, a great part of the lunar theory depends. For, 1. It is shown in the physical astronomy, that the force which diminishes the gravity of the moon in the syzygies, is double that which increases it in the quadratures: so that in the syzygies, the gravity of the moon, from the action of the sun, is diminished by a part which is to the whole gravity as 1 to 89,36: for in the quadratures, the addition of gravity is to the whole gravity as 1 to 178,73. 2. In the syzygies, the disturbing force is directly the distance of the moon from the earth, and inversely as the cube of the distance of the earth from the sun. And at the syzygies the gravity of the moon towards the earth, receding from its centre, is more diminished than according to the inverse ratio of the square of the distance from that centre. Hence, in the motion of the moon from the syzygies to the quadratures, the gravity of the moon towards the earth is continually increased, and the moon is continually retarded, in its motion; and in the motion from the quadratures to the syzygies, the moon's gravity is continually diminished, and its motion in its orbit accelerated. 3. Further, in the syzygies, the moon's orbit, or circle, round the earth, is more convex than in the quadratures, for which reason the moon is less distant from the earth at the former than the latter. When the moon is in the syzygies, her absides go backwards, or are retrograde.

When the moon is in the syzygies, the nodes move in antecedentia fastest: then slower and slower, till they become at rest, when the moon is in the quadratures.

Lastly, When the nodes are come to the syzygies, the inclination of the plane of the orbit is least of all. Add, that these several irregularities are not equal in each syzygy, but all somewhat greater in the conjunction than in the opposition.

Ꭲ,

T.

Ort, the nineteenth letter, and fifteenth consonant, of our alphabet, the sound whereof is formed by a strong expulsion of the breath through the mouth, upon a sudden drawing back of the tongue from the fore part of the palate, with the lips at the same time open. The proper sound of this letter is that in tan, ten, tin, &c. When it comes before i, followed by a vowel, it is sounded like s, as in nation, potion, &c. When h comes after it, it has a twofold sound; one clear and acute, as in thin, thief, &c. the other more obtuse and obscure, as in then, there, &c.

TABBYING, the passing a silk or stuff under a calendar, the rolls of which are made of iron or copper, variously engraven, which, bearing unequally on the stuff, renders the surface thereof unequal, so as to reflect the rays of light differently, making the representation of waves thereon.

TABERNÆMONTANA, in botany, so named in honour of James Theodore surnamed Tabernæmontanus, from Berg Zabern, the place where he was born; a genus of the Pentandria Monogynia class and order. Natural order of Contortæ. Apocina, Jussieu. Essential character: contorted; follicles two, horizontal; seeds immersed in pulp. There are nineteen species, among which we shall notice the T. cymosa, cyme-flowered tabernæmontana; this is an elegant upright little tree, or shrub, about six feet in height; leaves acute, quite entire, scarcely wav ed, half a foot long. Cymes ample, handsome, convex, axillary; flowers without scent, dirty white, or reddish brown, about forty in a cyme; tube of the corolla quinquangular, ventricose at the base; stamens in the enlarged base of the tube; stigma margined at the base; follicles oblong, very blunt, curved in, very large, reddish, with rust coloured spots; one of each pair is commonly abortive; the pulp is orange coloured. It is found in the woods and coppices about Carthagena in New Spain, flowering in July and August.

TABES dorsales, in medicine, a distemper which, according to a late author, is a particular species of a consumption, the proximate cause of which is a debility of the nerves.

TABLE, in perspective, denotes a plain surface, supposed to be transparent, and perpendicular to the horizon. It is always imagined to be placed at a certain distance between the eye and the objects, for the objects to be represented thereon, by means of the visual rays passing from every point thereof through the table to the eye; whence it is called perspective plane.

TABLE, among the jewellers. A tablediamond, or rather precious stone, is that whose upper surface is quite flat, and only the sides cut in angles; in which sense a diamond, cut table-wise, is used in opposition to a rose-diamond.

TABLE, is also used for an index or repertory, put at the beginning or end of a book, to direct the reader to any passage he may have occasion for: thus we say, table of matters, table of authors quoted, &c. Tables of the Bible are called concordances.

TABLE, in mathematics, a system of numbers calculated to be ready at hand for the expediting astronomical, geometrical, and other operations: thus we say, tables of the stars; tables of sines, tangents, and secants; tables of logarithms, rhumbs, &c.; sexagenary tables; loxodromic tables, &c.

TACCA, in botany, a genus of the Hexandria Monogynia class and order. Natural order of Coronaria. Narcissi, Jussieu. Essential character: calyx six-parted; corolla six-petalled, inserted into the calyx; anther bearing; stigma stellate; berry dry, hexangular, many-seeded, inferior. There is only one species, viz. T. pinnatifida; the root of which is tuberous, composed of many tubers heaped together, here and there emitting fibres; radical leaf, subsolitary, petioled, ternate, or biternate; leaflets laciniate pinnatified, acute, spreading, decurrent a little along the sides of the petiole, a foot in length; scape half a fathom in height herbaceous, fistular, grooved towards the top, erect; umbel terminating, sessile; peduncles four to eight; anthers twelve, on short filaments; germs three, or one three-lobed; styles three, short; stigma obcordate, two-lobed; berry black, seeds brown. It is a native of the East Indies, China, Cochin China, Banda, and the Society Isles.

TACK, in a ship, a great rope, having a wale-knot at one end, which is seized or fastened into the clew of the sail; so is reefed first through the chesse-trees, and then is brought through a hole in the ship's side. Its use is to carry forward the clew of the sail, and to make it stand close by a wind; and whenever the sails are thus trimmed, the main-tack, the foretack, and mizen-tack, are brought close by the board, and haled as much forward on as they can be. The bowlings also are so on the weather-side; the lee-sheets are haled close aft, and the lee-braces of all the sails are likewise braced aft. Hence they say, a ship sails or stands close upon a tack, i. e. close by the wind. The words of command are, hale aboard the tacks, i. e. bring the tack down close to the chesse-trees. Ease the tack, i. e. slacken it, or let it go, or run out. Let rise the tack, i. e. let all go out.

The tacks of a ship are usually belayed to the bitts, or else there is a chevil on purpose to fasten them.

TACK about, in the sea-language, is to turn the ship about, or bring her head about, so as to lie the contrary way. In order to explain the theory of tacking a ship, it may be necessary to premise a known axiom in natural philosophy, "that every body will persevere in a state of rest, or of moving uniformly in a right line, unless it be compelled to change its state by forces impressed; and that the change of motion is proportional to the moving force impressed, and is made according to the right line in which that force is exerted." By this principle it is easy to conceive how a ship is compelled to turn in any direction, by the force of the wind acting upon her sails in hori. zontal lines. For the sails may be so arranged as to receive the current of air either directly, or more or less obliquely; hence the motion communicated to the sails must of necessity conspire with that of the wind upon their surfaces. To make the ship tack, or turn round with her head to the windward, it is therefore necessary, after she has received the first impression from the helm, that the headsails should be so disposed as to diminish the effort of the wind, in the first instant of her motion, and that the whole force of the wind should be exerted on the after sails, which, operating on the ship's stem, carries it round like a weathercock. But since the action of the after-sails, to turn the ship, will unavoidably cease when her head points to the windward, it then becomes necessary to use the head-sails, VOL. XII,

to prevent her from falling off, and returning to her former situation. These are accordingly laid aback on the leeside, to push the vessel's fore-part towards the appointed side, till she has fallen into the line of her course thereon, and fixed her sails to conform with that situation.

TACKLE, or TACKLING, among seamen, denotes all the ropes or cordage of a ship, used in managing the sails, &c. In a more restrained sense, tackles are small ropes running in three parts, having at one end a pendant and a block; and at the other end a block and hook, to hang goods upon that are to be heaved into the ship, or out of it. See SHIP.

TACTICS, in their general acceptation, relate to those evolutions, manœuvres, and positions, which constitute the mainspring of military and naval finesse: they are the means whereby discipline is made to support the operations of a campaign, and are, in every regular service, studied, for the purpose of training all the component parts according to one regular plan or system; whereby celerity, precision, and strength, are combined, and the whole rendered completely efficient. Of military tactics, the Romans may be considered the first nation whose military array could be termed regular, and whose forces maintained that order, which rendered each inferior individual subject to the control of certain subaltern officers commanding small bodies, corresponding with our sections; which being again compacted under officers of a second class, formed small divisions, as in our platoons, or companies; and which divisions being collected under a third class of officers, constituted what we term battalions. The soldiers of ancient Italy were not only inured to great hardships, as a part of their usual exercise, but were taught many evolutions suited to the modes of warfare in those days.

Time has occasioned a considerable change in that particular; for since the invention of gunpowder, our battles have frequently been decided by distant can nonades; and by no means resembled those arduous conflicts in which the heroes of old used to engage, individually contending for the day, and causing the whole field to resemble an infinity of single combats. In this practice all barbarous nations seem uniformly to agree; the sword, the tomakawk, the club, &c. being the chief instruments; though, in some instances, the javelin, or spear, or the bow and arrow, may be primarily re

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