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Coach

noffus, Her ftatue was executed by Praxiteles; and fo exqui. fitely done, and fo much admired, that people came from all parts to view it, (Pliny). Of this place was Eudoxus, the famous aftronomer and geometrician, who had here an oblervatory, (Strabo).

CNOSSUS, or CNOSUS, anciently called Ceratos, from a cognominal river running by it; a city of Crete, 23 miles to the east of Gortina, (Peutinger). Here flood the fepulchre of Jupiter, the famous labyrinth, and the palace of Minos a very ancient king; here happened the adventure of Ariadne his daughter with Thefeus, called Gnofis, (Ovid). Its port-town was Heracleum, on the eaft fide of the island.

COACH, a vehicle for commodious travelling, fu fpended on leathers, and moved on wheels. In Britain, and throughout Europe, the coaches are drawn by horfes, except in Spain, where they ufe mules. In a part of the caft, especially the dominions of the great Mogul, their coaches are drawn by oxen. In Denmark they fometimes yoke rein-deer in their coaches; though rather for curiofity than ufe. The coachman is ordinarily placed on a feat raifed before the body of the coach. But the Spanish policy has difplaced him in that country by a royal ordonnance; on occafion of the Duke d'Olivares, who found that a very import ant fecret, whereon he had conferred in his coach, had been overheard and revealed by his coachman : fince that time the place of the Spanish coachman is the fame with that of the French ftage-coachman and our poftilion, viz. on the first horfe on the left.

The invention of coaches is owing to the French: yet coaches are not of any great antiquity, even in France, fcarce reaching beyond the reign of their Francis I. Their ufe, at their firft rife, was only for the country: and authors obferve, as a thing very fingular, that there were at first no more than two coaches in Paris; the one that of the queen, and the other that of Diana natural daughter of Henry II. The first courtier who had one was Jean de Laval de Bois Dauphin; whofe enormous bulk difabled him from travelling on horfeback. One may hence judge how much variety, luxury, and idleness, have grown upon our hands in later days; there being now computed in that fame city no lefs than 15,000 coaches.

Coaches have had the fate of all other inventions, to be brought by degrees to their perfection; at prefent they feem to want nothing, either with regard to cafe or magnificence. Louis XIV. of France made feveral fumptuary laws for reftraining the exceffive rich nefs of coaches, prohibiting the ufe of gold, filver, &c. therein; but they have had the fate to be neglected.

By the act 25 Geo. III. c. 47. former duties on coaches, &c. are repealed, and the following charged in lieu thereof, namely: For every coach, berlin, landau, chariot, calafh, with four wheels, chaife marine, chaife with four wheels, and caravan, or by whatever name fuch carriages may be called, kept by any perfon for his own ufe, or to be let out to hire (except hackney coaches), fhall be paid the yearly fum of L. 7. And for every calafh, chaife, chair, gig, or whifkey, or by whatever name they are known or called, having two or three wheels, to be drawn by one or more horfes, that fhall be kept by any perfon for his own ufe, or to be let out to hire, the yearly fum of L. 3, 108. Every maker of coaches, chaife, chariots, &c muft,

from and after the fifth day of July 1785, take out at the excife office in London, or of their agents in the country, a licence to be renewed annually at leaft ten days before the expiration of the former, for which they must pay 20s. They must alfo pay 208 duty for every four-wheeled carriage newly built for fale, and 10s. for every two-wheel carriage. Thefe duties are alto payable to the cominiffioners of the excife in town, or their agents in the country.

Coach-makers in Scotland are to take out their li cences and pay the duties to the commiffioners of excife in Edinburgh, or their agents in the country of that part of Great Britain.

Every coach-maker neglecting to take out a licence, and renewing the fame annually, forfeits L. 10; and neglecting or refufing to fettle every fix weeks, in the manner particularly directed by the act, is a forfeiture of L 20.

Hackney-Co.CHES, thofe expofed to hire, in the ftreets of London, and fome other great cities, at rates fixed by authority.

One thoufand hackney-coaches are allowed in London and Westminster; which are to be licensed by commiffioners, and to pay a duty to the crown. They are all numbered, having their numbers engraved on tin plates fixed on the coach-doors. Their fares or rates are fixed by act of parliament; and by a late act have been increased in confequence of a new weekly tax.

Stage-COACHES, are thofe appointed for the conveyance of travellers from one city or town to another. The matters of ftage coaches are not liable to an action for things loft by their coachmen, who have money given them to carry the goods, unlefs where fuck mafter takes a price for the fame.

Perfons keeping any coach, berlin, landau, or other carriage with four wheels, or any calafh, chaife, chair, or other carriage with two wheels, to be employed as public ftage coaches or carriages, for the purpofe of conveying paffengers for hire to and from different places, fhall pay annually 5s. for a licence; and no perfon fo licenfed fhall by virtue of one licence keep more than one carriage, under the penalty of L. 10.

Mail-CoACHES, are flage-coaches of a particular con. ftruction to prevent overturns; and for a certain confideration carry his Majefty's mails, which are protected by a guard, and fubject to the regulations of the poft-office. They are pointed as to their time of arrival and departure, are reftricted to four infide paffengers, and from experience have proved very beneficial to the commerce and correfpondence of this country. John Palmer, Efq; who has the merit of the invention, and been indefatigable in bringing the ellablishment to a permanent footing, has been greatly patronifed by government; and got, as the reward of his fervice, a handfome appointment in the general pol-office London.

COACH, or COUCH, is alfo a fort of chamber or apartment in a large fhip of war near the fern. The floor of it is formed by the aftmoft part of the quarter-deck, and the roof of it by the poop: it is generally the habitation of the captain.

COADUNATE, in botany, an order of plants in the fragmenta methodi naturalis of Linnæus, in which he has thefe genera, viz. annona, liriodendrum, magnotia, uvaria, michelia, thea.

COAGULATION, in chemistry, is performed by

Coach

Coagula.

tion.

Coal.

Coagulum fix different agents; and by each of these in feveral different manners. 1. It is performed with water, by congealing, crystallizing, and precipitating, as in the mercurius vitæ and fome other preparations. 2. With oil, which, by the force of fire, unites with fulphur, falts, and metals. 3. With alcohol, upon the fpirit of fal ammoniac, the white of eggs, the ferum of the blood, &c. 4. With acid and alkali growing folid to gether, as in the tartarum vitriolatum. 5. With fixed alkali, as in milk. And, 6. With acid falts; as in milk, ferum, and the whites of eggs.

COAGULUM, is the fame with what in English we call runnet, or rather the curd formed thereby. COAKS. For the exciting of intense heats, as for the fmelting of iron ore, and for operations where the acid and oily particles would be detrimental, as the drying of malt, foffil coals are previously charred, or reduced to coals; that is, they are made to undergo an operation fimilar to that by which charcoal is made. By this operation coals are deprived of their phlegm, their acid liquor, and part of their fluid oil. Coaks, therefore, confit of the two mot fixed conftituent parts, the heavy oil and the earth, together with the acid concrete falt, which, though volatile, is diffolved by the oil and the earth.

COAL, among chemifts, fignifies any fubftance containing oil, which has been expofed to the fire in clofe veffels, so that all its volatile principles are expelled, and that it can fuftain a red heat without further decompofition. Coal is commonly folid, black, very dry, and confiderably hard. The fpecific' character of perfect coal is its capacity of burning with accefs of air, while it becomes red-hot and fparkles, fometimes with a fenfible flame which gives little light, with no smoke or foot capable of blackening white bodies.

Coal is capable of communicating its inflammable principle, either to the vitriolic acid with which it forms fulphur; or to the nitrous acid contained in nitre, which it inflames; or to metallic earths, which it reduces into metals. But the phlogifton cannot pafs from coal to form these new combinations without the affiftance of red-heat. Coal feems to be an unalterable compound in every inftance but those mentioned, of burning in the open air, and of communicating its phlogiston to other bodies: for it may be expofed in clofe veffels to the most violent and long continued fire without fuffering the leaft decompofition. No difpofition to fufe, nor any diminution of weight, can be perceived. It is a fubftance exceedingly fixed, and perhaps the most refractory in nature. It refifts the action of the moft powerful menftrua, liver of fulphur alone excepted. Coal is evidently a refult of the decompofition of the compound bodies from which it is obtained. It confifts of the greatest part of the earthy principle of thefe compound bodies, with which a part of the faline principles, and fome of the phlogiton of the decompofed oil, are fixed and combined very intimately. Coal can never be formed but by the phlogiflon of a body which has been in an oily ftate: hence it cannot be formed by fulphur, phofphorus, metals, nor by any other fubftance the phlogifton of which is not in an oily ftate. Alfo every oily matter treated with fire in clofe veffels, furnishes true coal; fo that whenever a charry refiduum is left, we may be certain

that the fubftance employed in the operation contained oil. Laftly, the inflammable principle of coal, altho' it proceeds from oil, certainly is not oil; but pure phlogifton; fince coal added to vitriolic acid can form fulphur, to phosphoric acid can form phofphorus, &c, and fince oil can produce none of these effects till it has been decompofed and reduced to the state of coal. Befides, the phenomena accompanying the burning of coal are different from thofe which happen when oily fubftances are burnt. The flame of charcoal is not fo bright as that of oil, and produces no flame or foot.

All the phlogifton of coal is not burnt in the open air, particularly when the combuftion is flow. One part of it exhales without decompofition, and forms a vapour, or an invifible and infenfible gas. This vapour (which is, or at leaft contains a great deal of, fixed air) is found to be very pernicious, and to affect the animal fyftem in fuch a manner as to occafion death in a very short time. For this reafon it is dangerous to remain in a close place, where charcoal or any other fort of coal is burnt. Perfons ftruck by this vapour are tunned, faint, fuffer a violent headach, and fall down fenfclefs and motionlefs. The best method of recovering them is by expofure to the open air, and by making them fwallow vinegar, and breathe its fleam.

Amongst coals, fome differences are obfervable, which proceed from the difference of the bodies from which they are made: fome coals, particularly, are more combustible than others. This combuftibility feems to depend on the greater or lefs quantity of saline principle they contain; that is, the more of the faline principle it contains, the more eafily it decompofes and burns. For example, coals made of plants and wood containing much faline matter capable of fixing it, the afhes of which contain much alkaline falt, burn vigorously and produce much heat; whereas the coals of animal matters, the faline principles of which are volatile, and cannot be fixed but in fmall quantity, and the afhes of which contain little or no falt, are scarcely at all combustible. For they not only do not kindle fo cafily as charcoal does, nor ever burn alone, but they cannot be reduced to afhes, without very great trouble, even when the most effectual methods are used to facilitate the combuftion. The coal of bullocks blood has been kept for fix hours very red in a shallow crucible, furrounded with burning charcoal, and conftantly ftirred all the time, that it might be totally expofed to the air; yet could it not be reduced to white, or even grey, afhes: It ftill remained very black, and full of phlogifton. The coals of pure oils, or of concrete oily fubflances and foot, which is a kind of coal raifed during inflammation, are as difficultly reduced to afhes as animal coals. Thefe coals contain very little faline matter; and their afhes yield no alkali. The coals which are fo difficultly burnt, are alfo lefs capable of inflaming with nicre than others more combustible; and fome of them even in a great measure refift the action of nitre.

COAL, in mineralogy, a kind of folid inflammable fubftance, fuppofed to be of a bituminous nature, and commonly used for fuel. Of this fubftance there are various fpecies.

1. Pit-coal (Lithanthrax), is a black, folid, compact,

Coals.

Coal.

pact, brittle mass, of moderate hardness, lamellated ftructure, more or lefs fhining, but seldom capable of a good polish; and does not melt when heated. According to Kirwan, it consists of petrol or asphaltum, intimately mixed with a fmall portion of earth chiefly argillaceous; feldom calcareous; and frequently mixed with pyrites. A red tincture is extracted from it by fpirit of wine, but caustic alkali attacks the bituminous part. From fome forts of it a varnish may be made by means of fat oils. Fixed alkali has never been found in any kind of it, nor fulphur, unless when it happens to be mixed with pyrites.-None of the various kinds are found to be electrics per fe (A).

The varieties of lithanthrax, enumerated by Cronstedt, are, 1. With a fmall quantity of argillaceous earth and vitriolic acid. It is of a black colour, and fhining texture: it burns, and is moftly confumed in the fire, but leaves, however, a fmall quantity of afhes. 2. Slaty coal.

2. Culm coal, called kolm, by the Swedes, has a greater portion of argillaceous earth and vitriolic acid, with a moderate proportion of petrol. It has the fame appearance with the foregoing, though its texture is more dull: it burns with a flame, without being confumed, but leaves behind it a flag of the fame bulk with the original volume of the coal. The following is Mr Kirwan's description of it from the memoirs of the Stockholm academy. "Its fracture has a rougher section than the cannel coal; its fpecific gravity from 1300 to 1370. The best kind affords by diftillation, at firft fixed air, then an acid liquor, afterwards inflammable air, and a light oil of the nature of petrol; then a volatile alkali; and lastly pitchoil. The refiduum is nearly three quarters of the whole; and being flowly burnt, affords 13 per cent. of afhes, which confift moftly of argillaceous earth; and about three hundredth parts of them are magnetic. It is found in England, and among fome aluminous ores in Sweden."

3. Slate-coal contains fuch a quantity of argillaceous earth, that it looks like common flate; however, it burns by itself with a flame. M. Magellan is of opinion that this is the bituminous fubftance already defcribed (fee CLAY, p. 51.) This fchiftus is of a dark bluish rufty colour; when thrown on the fire it burns with a lively flame, and almost as readily as the oily wood of dry olive tree, or lignum vitæ; emitting the very difagreeable fmell of petrol. Such large quarries N° 83.

of it are found near Purbeck in Dorfetfhire, that the poorer part of the inhabitants are thence fupplied with fuel. From the appearance of this flaty coal, Cronftedt has been induced to fuppofe that the earth of all kinds of coal is argillaceous, though it is not fo eafy to diftinguish it after being burnt. The pit-coals, he fays, contain more or lefs of the vitriolic acid; for which reafon the smoke arifing from them attacks filver in the fame manner as fulphur does, let the coals be ever fo free from marcafite, which, however, is often imbedded or mixed with them.

4. Cannel coal (Ampelites), is of a dull black colour; breaks eafiy in all directions; and, if broken tranfverfely, prefents a smooth conchoidal surface. It burns with a bright lively flame, but is very apt to fly in pieces in the fire; however it is faid to be entirely deprived of this property by immerfion in water for fome hours previous to its being used. It contains a confiderable quantity of petrol in a lefs condensed state than other coals. Its fpecific gravity is about 1.270. This kind of coal, being of an uniform hard texture, is eafily turned on a lath, and takes a good polish. Hence it is ufed for making various toys, which appear almost as well as if made of the finest jet.

5. Kilkenny coal is the lighteft of any; its specific gravity being only about 1400. It contains the largeft quantity of afphaltum; burns with lefs fmoke and flame, and more intenfely, though more flowly, than the cannel-coal. The quantity of earth it contains does not exceed one twentieth part of its weight; but this kind of coal is frequently mixed with pyrites. It is found in the county of Kilkenny, belonging to the province of Leinfter in Ireland. The quality of it as burning without fmoke, is proverbially used as an encomium on the county.

6. Sulphureous coal confifts of the former kinds mixed with a very confiderable portion of pyrites; whence it is apt to moulder and break when exposed to the air, after which water will act upon it. It contains yellow fpots that look like metal; burns with a fulphureous fmell, leaving behind it either flag or fulphureous afhes, or both. Its fpecific gravity is 1500

or more.

7. Bovey coal (Xylanthrax), is of a brown or brownish black colour, and of a yellow laminar texture. Its lamine are frequently flexible when firft dug, though they generally harden when exposed to the

(A) "The varieties of this coal (fays Mr Magellan) are very numerous according to the different fubftances with which it is mixed; but in regard to their economical ufes, only two kinds are taken notice of by the British legislature, viz. culm and caking coals. The caking coals, in burning, fhow an incipient fufion, fo that their finalleft pieces unite in the fire into one mafs; by which means the fmallest pieces, and even the mere duft of this kind, are almost equally valuable with the largest pieces. The other fort called culm, does not fufe or unite in the fierceft fire; so that the small coal, being unfit for domestic purposes, can only be used in burning limeftone.

"It should be an eafy matter for any perfon to diftinguish culm from fmall caking coal, either by trying to make fire with it in a common grate, without interpofing any other fuel between it; when if it kindles, it is a caking coal; if not, it is culm: Or by putting fome of thefe fmall fragments of coal on an ignited iron fhovel; if they melt and run together, they belong to the caking kinds; if not, they are culm. But it feems that coal merchants are now in the cuftom of calling culm the powdery parts of pitcoal, of whatfoever kind they may happen to be. The reafon of this is, that there is a difference in the duty payable by culm and by caking coals. There never was any difficulty, however, on the fubject; nor would there be any difficulty in collecting the tax, were it not for the infufferable ignorance and love of defpotic oppreffion which generally pervades the underling officers of the revenue."

Coal.

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