During the performance of the hymn, he remarked the iteration of the words, and the frequent returns of ut, re, mi, fa, sol, la: he observed likewise a dissimilarity between the closeness of the syllable mi, and the broad open sound of fa, which he thought could not fail to impress upon the mind a lasting idea of their congruity; and immediately conceived a thought of applying the six syllables to perfect an improvement either then actually made by him, or under consideration, viz. that of converting the ancient tetrachords into hexachords.

Struck with the discovery, he retired to his study; and having perfected his system, began to introduce it into practice: the persons to whom he communicated it were the brethren of his own monastery, from whom it met with but a cold reception, which, in the epistle to his friend, he ascribes undoubtedly to its true cause, envy: however, his interest with the abbot, and his employment in the chapel, gave him an opportunity of trying the efficacy of his method on the boys who were training up for the choral service, and it exceeded the most sanguine expectation. "To the admiration of all (says cardinal Baronius), a boy thereby learnt, in a few months, what no man, though of great ingenuity, could before that attain in several years."

The fame of Guido's invention soon spread abroad, and his method of instruction was adopted by the clergy of other countries: we are told by Kircher, that Hermanus bishop of Hamburg, and Elviricus bishop of Osnaburg, made use of it; and by the authors of the Histoire Litéraire de la France, that it was received in that country, and taught in all the monasteries in the kingdom. It is certain that the reputation of his great skill in music had excited in the pope a desire to see and converse with him; of which, and of his going to Rome for that purpose, and the reception he met with from the pontiff, he himself has given a circumstantial account.

ARETOLOGY, that part of moral philosophy which treats of virtue, and the means of arriving at it.

AREZZO, an ancient town of Florence, in Italy, seated on a mountain. Lat. 43. 27 N. Lon. 12. 0 E.

ARGAL, or ARGOL, the tartar adhering to the sides of the teeth. ARGALI.

See OVIS.

ARGEA, in Roman antiquity, thirty human figures, made of rushes, thrown annually by the priests or by the vestals into the Tiber, on the day of the Ides of May. Different reasons are assigned for this ceremony.

ARGE/MONE. Prickly poppy: a genus of the class and order polyandria monogynia. Calyx three-leaved; petals six; capsule halfvalved. Three species; Mexico, Arminia, Pyrennees,

ARGENT, the common French word for silver, of which metal all white fields or charges are supposed to consist. Argent of itself is used in heraldry to signify purity, innocence, beauty, and gentleness.

ARGENTAL MERCURY, a native amalgam of silver, by which name it was formerly known. It received its present appellation from C. Hauy, whose experiments have made us acquainted with many of its properties: from its great rarity, however, it is as yet but imperfectly known, scarcely any person besides having examined it with much attention. This mineral is found in the mines of Hungary; and, when separated from its ore, has the colour and resplendence of silver or polished tin, or rather more frequently of liquid mercury, because it generally retains at its surface a thin stratum of that metal. Its crystals are dodecaedral-rhomboidal, in various modifications. Its specific gravity is 141192, being considerably greater than that of either of the two metals of which it is composed. This substance has been carefully analysed by C. Cordier, engineer of mines in France, and found to contain 72.5 parts of mercury to 27.5 of silver: it appears also to be a real chemical combination of the two metals, and not a paste-like mixture, from which circumstance the propriety of its present name instead of the former one of an amalgam, is obvious. See the Philosophical Magazine, vol. xiv. p. 41; or Journal des Mines, No. 67.

ARGENTINE FLOWERS OF ANTIMONY. See ANTIMONY.

ARGENTARIUS, in antiquity, a moneychanger, or banker.

ARGENTEUIL, a town of the isle of France. Lat. 48. 52 N. Lon. 2. 22 E.

ARGENTEUIL, a town of France, in the department of the Yonne; three leagues from Tonnerre.

ARGENTICOMUS, among astrologers, a silver-haired comet, from the appearance of which great changes in our system are predicted.

ARGENTINA. Argentine. In zoology, a genus of the class and order pisces abdomina lia. Teeth in the jaws and tongue; gill-mem brane with eight rays; vent near the tail; ventral fins of many rays. Four species, two inhabitants of the Red sea, one Mediterranean, one fresh waters of Carolina. A. sphyræna is the European argentine. Anal fin with nine rays: inhabits the Mediterranean, and sometimes wanders to the British coasts: from two to four inches long: body round, tapering; back and sides, as far as the lateral line, pale ash mixed with green; below the line and belly fine silvery: air-bladder conic both sides, appearing as if covered with silver leaf, and is used in the manufacture of artificial pearls.

ARGENTINE. See ARGENTINA.

ARGENTIERRA, an island near that of Milo, in the Archipelago. It receives its name from the silver mines found in it. Lat. 36. 50 N. Lon. 23. 10 E.

ARGENTON, a town of France, in the department of Indre. Lat. 46. 35 N. Lon. 1.38 E. ARGENTUM. Silver. Of a whitish colour not tarnished by the air, hard and tenacious, sonorous, exceedingly malleable, and ductile, specific gravity before hammering 10-478 melting when perfectly red hot, and its brilliancy much increased. Soluble in nitric acid; giving no colour to the solution, and capable of being precipitated from it by copper, iron, or zinc. Thirteen species. We shall

enumerate a few.

1. A. nativum. Native, or capillary silver. Found in various parts of Great Britain, particularly in the copper mines of Cornwall; in the mines of Mexico and Peru, and in most of the mines on the continent. Rarely to be met with quite pure, but most commonly combined with a greater or less proportion of copper, and has sometime, its surface striate: assumes various forms, and is occasionally found in prisms or cubes. In malleability it yields only to gold, as it may be beaten out into leaves the 160,000th part of an inch thick; and may be drawn out to so fine a wire that a single grain can be extended nearly 400 feet in length. Its tenacity is likewise such that a wire 0-078 of an inch in diameter will support 17,313 pounds without breaking. When melted, if the heat be increased, the liquid metal boils, and will at last be volatilized. When dissolved in nitric acid and precipitated in lime water, it falls to the bottom in the form of a dark greenishbrown powder. When dissolved in nitric acid and precipitated with mercury, it shoots up in a shrub-like form, and is then called arbor diana. Its solution is colourless, highly caustic, giving the hair, skin, and almost all animal substances, an indelible black colour; and when evaporated till a pellicle begins to form on its surface, it deposits on cooling transparent crystals of nitrat of silver (see ARGENTUM NITRATUM). If its precipitate by lime water be dried and washed with a solution of pure ammonia, it has a most dangerous fulminating property, exploding most violently on the slightest touch or friction. This powder is denominated fulminating powder, or pulvis fulminans.

2. A. nigrum. Black silver. Black silver ore. Found in the silver mines of Sicily, Britanny, Saxony, Hungary, and Bohemia, sometimes covering other minerals as with a coating; sometimes interspersed in larger or less particles, or in a pulverised state: commonly combined with sulphur, arsenic, copper, or a little iron.

3. A. corneum. Corneous silver: corneous silver-ore. Muriat of silver: the last name from its containing a considerable portion of muriatic acid. Found in the mines of Mexico, Peru, Siberia, Hungary, Bohemia, Saxony, and Germany. It melts before a candle like wax or suet; and before the blow-pipe leaves small grains of pure silver. Soft and easily cut with a knife. Colour white, grey, yellowish, green, yellow, or brown.

in the mountain Schlangenburg in Siberia, and in the mines Kongsburg in Norway, of a pele brass colour: sometimes containing 28 of gold and 72 silver in the 100.

5. A. stibiatum. Antimonial silver ore; or antimonial native silver. Found near Wittichen in the district of Turstenburg.

6. A. vitreum. Vitreous silver; sulphuret of silver: sulphurated silver ore. Found in the mines of Siberia, Norway, Saxony, Bohe mia, Hungary, Spain, and America, generally superficial, and running like veins through

other fossils. It is one of the richest ores of silver; usually containing 85 per cent. of pure silver.

7. A. rubrum.

Ruby silver ore. There are two varieties, light red silver ore and dark red silver ore. Found in various mines of Peru, Chili, France, Spain, Gerinany, Saxony, Hungary, &c. with arsenic, galena, or other ores of silver. Contains silver 56, antimony 16, sulphur 15, oxygen 12, and a little arsenic.

ARGENTUM ALBUM, in our old customs, silver coin, or pieces of bullion that passed for

money.

ARGENTUM DEI, anciently signified earnest money, or that given to bind a bargain. ARGENTUM FULMINANS, or FULMINATING SILVER, which see, as also ARGEN

TUM.

ARGENTUM MOSAICUM, or Musivum, a metallic alloy in the form of silvery flakes, used for the colouring of plaster figures, and for other purposes, as a pigment. It is formed of equal parts of tin, bismuth, and mercury; and may therefore be called a compound amalgam. When used, it is mixed with white of eggs, or spirit varnish, and then applied to the proposed work, which is afterwards to be burnished.

ARGENTUM NITRATUM. Causticum lunare. Lunar caustic. This preparation of silver is called nitras argenti fusus in the new chemical nomenclature. Its virtues are corrosive and adstringent. Internally it is exhibited in very small quantities in epilepsy; and externally it is employed to destroy fungous excrescences, callous ulcers, fistulas, &c. In the latter disease it is injected in the quantity of from two grains to three dissolved in an ounce of water.

ARGENTUM VIVUM. See HYDRARGY

RUS.

ARGESTES, is used by Vitruvius for the wind which blows from that quarter of the horizon, which is 75 deg. from the south, and westward. Ricciolus uses the term to denote the wind which blows at 22 deg. 30 min. from the west towards the north, coinciding with that which is otherwise called West-NorthWest.

ARGETENAR, a small fixed star in Eri

danus.

with a small proportion of carbonat of lime, and sometimes a slight quantity of iron and silex. Mineral acids dissolve it. This mineral is chiefly, if not exclusively, brought from Halle, in Saxony. Its specific gravity, according to Bergman, is 1-305, to Gmelin 1.669. ARGILLA. Argil. A genus of the class earths, order argillaceous: consisting of alumina and silica with generally some oxyd of iron and inflammable matter; opake, without lustre; of a common form; soft to the touch; earthy, lightish, unbibing and retaining water, and oil, by each of which it is softened, and rendered plastic by the former, and emitting an earthy smell: not effervescing with nitric acid, contracting and becoming harder in the fire. Thirty species: the following the chief. 1. A porcellana. Porcelain earth or clay. It is found loose, in a compact form, in a powdery form, and mixed with micaceous parucles. Cornwall, Japan, China, Saxony, and various parts of Europe; and is supposed to originate from decomposed feldspar. It is principally used in the manufacture of China ware. Contains alumina 60, silica 20, air and

water 12.

2. A. leucargilla. Pipe-clay; potters'-clay: common clay. Found very generally in Europe; especially in Normandy, near Cologne, and in Livonia. Colour varying from pure white to black, often variegated. When first exposed to heat it becomes blackish from the inflammable matter it often contains; but by continued heat it turns pure white. It is used for tobacco pipes and various vessels.

3. A. lithomarga. Lithomarge: potter's clay of Thomson. Several varieties. Found in various parts of the world in clay and lime stone rocks, in long layers between clay and limestone, sometimes compact, sometimes in the form of powder of various colours: alters its colour by fire, becomes very hard, and by continued heat melts into a red porous clay. It is entirely diffusible by water; and when duly moistened very ductile, on which account it is highly useful in potteries and China-manufactories.

4. A. fullonica. Fullers' earth. Found in Britain, Sweden, Saxony, and Portugal: brown or grey, with generally a shade of green; rarely flesh-colour. Receives a polish from friction, does not adhere to the tongue; feels greasy. From the great avidity with which it absorbs oil, it is used by fullers to take grease out of cloth.

5. A. lemnia. Lemnian earth. Found chiefly in the isle of Lemnos and in Silesia. Formerly used as a bole in medicine.

6. A. communis. Common clay. Several varieties. Found in almost every part of the globe, frequently forming vast strata below the surface, and often bearing the impressions of vegetables. Colour blueish and yellowish grey, smoke-colour, dull blueish, rarely green or flesh-colour, and impregnated with a greater or less degree of silica.

7. A. cimolia. Cimolite. Found in the isle of Argentiers in the Archipelago, where it

is used for whitening stuffs. Pearl-grey co lour, becoming white before the blow-pipe.

8. A. rubrica. Reddle. Found in Siberia, Dalecarlia, Bohemia, Portugal, and France, generally among iron ore, with which it commonly abounds. Colour dark cochineal red, or intermediate between brick and blood red.

9. A. lutea. Yellow ochre. Found near Wetran. Feels smooth or somewhat greasy. Contains alumina 50, oxyd of iron 40, water acidulated by sulphuric acid 10.

10. A. arvensis. Field-clay. Loam. Cinereous, forming small clods when moistened, splitting into large clefts while drying, and be coming at last powdery, vitrifying in the fire. Found every where in cultivated lands.

ARGILLA CEOUS. a. (from argil.) Clay ey; consisting of argil, or potters' clay. ARGILLACEOUS EARTHS. An order containing principally aluminous earths. See ALUMINE and ORYCTOLOGY.

ARGILLOUS. a. (from argil.) Consist ing of clay; clayish; containing clay (Brown). ARGNES (Gerard d'), a French mathema tician, was born at Lyons, in 1597, and died there in 1661. He was the friend of Descartes, whom he defended with great spirit. He wrote a treatise on Perspective; of Conic Sections; the Practice of Drawing; and a treatise on Stonecutting.

ARGO, in antiquity, a ship or vessel celebrated among the poets; being that wherein the argonauts, of whom Jason was the chief, made their expedition in quest of the golden fleece. Sir Isaac Newton thinks that this expedition was really an embassy sent by the Greeks, during the intestine divisions of Egypt, in the reign of Amenophis, to persuade the nations upon the coasts of the Euxine and Mediterranean seas to take that opportunity of shaking off the yoke of Egypt, which Sesostris had laid upon them: and that fetching the golden fleece was only a pretence to cover their true design.

ARGÖL, or ARGAL, in chemistry, the same as tartar.

ARGOLIS, so called from an ancient prince whose name was Argos, one of the six districts of Peloponnesus, situated on the northeast side, was bounded by Achaia on the north, Arcadia on the west, Laconia and the Argolic gulf on the south, and the gean sea on the east. This province is peculiarly interesting to the Grecian antiquarian and historian, because it was the cradle of the Greeks, since it first received the foreign colonies by whom they were civilized.

ARGONAUTA. In zoology, a genus of the class and order vermes testacea. Animal a sepia or clio: shell univalve, spiral, involute, membranaceous, one-celled. Five species. The following is well entitled to notice.

A. argo.

Nautilus. Keel or ridge of the shell slightly toothed on each side. Inhabits the Mediterranean and Indian ocean, and was supposed in former ages to have taught mankind the first use of sails. When it means to sail, it discharges a quantity of water, by

which it was made heavier than the sea-water, and rising to the surface erects its arms, and throws out a membrane between them; by which contrivance it is driven forwards like a vessel under sail, hanging two of its arms over the shell, to serve as oars or as a rudder. The nautilus in the Linnéan system is an animal somewhat different from the argonauta; for which, sec NAUTILUS.

ARGONAUTIC, something relating to the argonauts. The argonautic expedition is one of the greatest epochas which sir Isaac Newton endeavours to settle, and from thence to rectify the ancient chronology. This he shews, by several authorities, to have been one generation, or about thirty years earlier than the taking of Troy; and forty-three years later than the death of Solomon.

ARGONAUTS, in antiquity, a company of fifty-one, according to Valerius Flaccus, or according to Apollonius Rhodius, forty-four heroes, who embarked along with Jason in the ship Argo for Colchis, with a design to obtain the golden fleece.

ARGO NAVIS, in astronomy, the Ship Argo, a southern constellation, containing 48 stars in the following order, 1 6.11.13.14.3. ARGOPHYLLUM. In botany, a genus of the class and order pentandria monogynia. Calyx five-cleft, superior; corol five-petalled; nectary pyramidal, five-angled, as long as the corol; capsule three-celled, many-seeded. The only known species is a native of New Cale

donia.

ARGOS, a seaport of Turkey in Europe, in the Morea: 25 miles S. of Corinth. Lat. 37. 30 N. Lon. 23. 5 E.

ARGOSY. s. (from Argo, the name of Jason's ship.) A large vessel for merchandise; a carrack (Shakspeare).

To A'RGUE. v. n. (arguo, Latin.) 1. To reason; to offer reasons (Locke). 2. To persuade by argument (Congreve) 3. To dispute (Locke).

To ARGUE. v. a.

1. To

prove any thing by argument (Doune). 2. To debate any question. 3. To prove, as an argun.ent (Milton). 4. To charge with, as a crime (Dry.). A'RGUER. s. (from argue.) A reasoner; a disputer; a controvertist (Atterbury).

ARGUIN, an island of Africa, on the western coast of Negroland. The Dutch took this place from the Portuguese in 1638, and the French took it from the Dutch. Lat. 20. 30 N. Lon. 17. 20 W.

ARGUMENT. s. (argumentum, Lat.) 1. A reason alleged for or against any thing (Locke). 2. The subject of any discourse or writing (Milton. Sprat). 3. The contents of any work summed up by way of abstract (Dryden). 4. Controversy (Locke).

ARGUMENT, in astronomy, is used to denote any known arch or quantity, by which another required arch or quantity may be found. For example, the argument of that part of the equation of time which arises from the unequal angular motion of the carth in its orbit, is the sun's anomaly, because that part of

the equation depends entirely upon the anomaly. Again, the argument of the moon's or a planet's latitude is its distance from its node, because upon this the latitude depends.

ARGUMENT, in rhetoric, is some reason, or series of reasoning, by which we establish the proof, or shew the probability, of some given proposition.

Logicians, somewhat more scientifically, define argument, a medium, from whose connection with two extremes, the connection of the two extremes themselves is inferred.

Arguments are termed grammatical, logical, physical, metaphysical, moral, mechanica!, theological, &c. according to the art, science, or subject, from whence the middle tern is borrowed. Thus, if we prove that no man should steal from his neighbour, because the scripture forbids it; this is a theological argument: if we prove it from the law of the land; it is political: but if we prove it from the principles of reason and equity; the argument is moral. Arguments are either certain and evident, or doubtful and merely probable. Probable arguments are those whose conclu sions are proved from some probable medium. Evident and certain arguments, are those which prove their conclusions by clear media and undoubted principles: these are called demonstrations. In reasoning, Mr. Locke observes, that men ordinarily use four sorts of arguments. The first is to allege the opinions of men, whose parts and learning, eminency, power, or some other cause, have gained a name; and settled their reputation in the common esteem, with some kind of authority: this may be called argumentum ad verecun dium. Secondly, another way is to require the adversaries to admit what is alleged, as a proof; or to assign a better: this he calls argu mentum ad ignorantiam. A third way, is to press a man with consequences, drawn from his own principles or concessions: this is known by the name of argumentum ad hominem. Fourthly, the using proofs drawn from any of the foundations of knowledge or proba bility: this he calls argumentum ad judicium; and observes, that it is the only one of all four, that brings true instruction with it; and advances us in our way to knowledge.

ARGUMENTAL. a. (from argument.) Belonging to argument; reasoning (Pope). ARGUMENTATION. s. (from argu

ment.) (Watts).

Reasoning; the act of reasoning ARGUMENTATIVE. a. (from argu ment.) Consisting of argument; containing argument (Alterbury).

ARGUMENTUM AD HOMINEM. See ARGUMENT.

ARGUS, in fabulous history, the son of Aristor, was said to have had a hundred eyes, fifty of which were always open. Juno made choice of him to guard Io, whom she had transformed into a white heifer; but Jupiter pitying Io, for being so closely coutined, sent Mercury, who, with his flute, charmed Argus to sleep, scaled up his eyes with his cadu

eeus, and cut off his head: Juno, to reward his fidelity, turned him into a peacock, and placed his eyes in the tail.

ARGUS is also the name of a very curious shell, about three inches long, two in diameter, and somewhat less in height. It is cover ed with a multitude of round spots, like eyes, from whence it has its name. It is brought from Africa and the East Indies.

ARGUTE. a. (arguto, Ital. argutus, Lat.) 1. Subtile; witty; sharp. 2. Shrill.

ARGUTIÆ, witty and acute sayings, which commonly signify something further than what their inere words at first sight seem to import.-Writers on rhetoric speak of divers species of argutiæ, which are of too little consequence to require a particular enumeration. ARGYLESHIRE, a county of Scotland, bounded on the N. by Invernessshire, on the E. by the counties of Perth and Dumbarton, on the S. and W. by the Atlantic ocean, by which it is broken into islands and peninsulas. It is not quite 100 miles long from the Mull of Cantyre to its N.E. extremity: its breadth is unequal; about 30 miles where greatest. It contains more than 71,000 inhabitants.

ARGYRASPIDES, or ARGYROASPIDES, in antiquity, persons armed with silver bucklers, or bucklers silvered. The argyraspides, according to Quintus Curtius, made the second corps of Alexander's army; the first was the phalanx.

ARGYRITE AGONES, in antiquity, games in which money was the prize.

ARGYTHA'MNIA. In botany, a genus of the class and order mondecia tetrandria. Male: calyx four-leaved; petals four. Female: calyx five-leaved; corolless; styles three, forked; capsule three-celled; seeds solitary The only known species is a native shrub of Jamaica.

ARIA DI BRAVURA, in music, or, as it is familiarly called, a Bravura, is a melody at once florid, rapid, and energetic. Its divisions are volatile, and the passages every-where bold and heroic. The execution of this species of air is generally confined to soprano voices; and it is only to powers of the first order that we can look for its just performance.

ARIA FUGATA. (Ital.) Fugued air. An elaborate species of melody much used in the last age, and frequently found in the operas of Handel, Bononcini, and their contemporaries. The aria fugata was so called, because the accompanying parts were written in fugue. This laboured kind of song-writing is now judiciously declined.

ARIADNÆA, in antiquity, two festivals held at Naxos in honour of two women named Ariadne. One of these festivals was mourn ful, the other sprightly and cheerful; corresponding with the different characters of the

two women.

ARIADNE, daughter of Minos 2d king of Crete, by Pasiphae, fell in love with Theseus, who was shut up in the labyrinth to be devoured by the Minotaur. She gave him a clue of thread, by which he extricated himself

from the different windings of his confinement. After he had conquered the Minotaur, he carried her away and married her; but he afterwards forsook her, though already pregnant. Ariadne was so disconsolate upon being abandoned by Theseus, that she hung herself. According to some writers, Bacchus loved her after Theseus had forsaken her, and he gave her a crown of seven stars, which, after her death, were made a constellation.

ARIANS, followers of Arius, a presbyter of the church of Alexandria about the year 315; who maintained that the Son of God was totally and essentially distinct from the Father; that he was the first and noblest of those beings whom God had created, the instrument by whose subordinate operation he formed the universe; and therefore inferior to the Father both in nature and dignity; also, that the Holy Ghost was not God, but created by the power of the Son.

The Arians owned that the Son was the word, but denied that word to have been eternal. They held that Christ had nothing of man in him but the flesh, to which the λoyo; or word was joined, which was the same as the soul in us. (See Lardner's Credibility, &c. vol. ix. b. i. c. 69.) The Arians were first condemned and anathematized by a council at Alexandria in 320, and afterwards by 380 fathers in the general council of Nice, assembled by Constantine in the year 325. They also underwent various revolutions, persecuting and being oppressed by turns, under succeeding emperors, according to the degree of interest they had in the civil power, till at length Theodosius the Great exerted every possible effort to suppress and disperse them.

The Arians were divided into various sects, of which ancient writers give an account un der the names of Semi-Arians, Eusebeans, Aetians, Eunomians, Acacians, Psathyrians, and others. But they have been commonly distributed into three classes, viz. the Genuine Arians, Semi-Arians, and Eunomians. The appellation Arian has been indiscriminately applied, in more modern times, to all those who consider Jesus Christ as inferior and subordinate to the Father; and whose sentiments cannot be supposed to coincide exactly with those of the ancient Arians.

ARICA, a sea-port town of Peru, in South America. It was destroyed by an earthquake in 1605. Great quantities of Guinea pepper, are sent from this place to Lima. It was the port to the mines of Potosi; but the silver has been carried over land to Lima for many years. Lat. 18. 27 S. Lon. 71. 6 W.

ARICA, supposed by Camden to be the island of Alderney, on the coast of France. A'RID. a. (aridus, Lat.) Dry; parched up (Arbuthnot).

ARIDED, or ADIGEGE, a fixed star of the 2nd magnitude, marked a in Cygnus.

ARIDITY. s. (from arid.) 1. Dryness; siccity (Arbuthnot). 2. A kind of insensibility in devotion, contrary to unction or tenderness (Norris).