The firestone, or pyrites, is a compound metallic fossil, composed of vitriol, sulphur, and an unmetallic earth, but in very different proportions to the several masses. It has its name of pyrites or firestone, from its giving fire on being struck against a steel much more freely than a flint will do; and all the sparks burn a longer time, and grow larger as they fall, the inflammable matter struck from off the stone burning itself out before the spark becomes extinHill's Mat. Med. guished. Prime all your firelocks, fasten well the stake. Gay. The fireman sweats beneath his crooked arms; A leathern casque his vent'rous head defends, Boldly he climbs where thickest smoke ascends. Id. Dim are his torches, and extinct his fires. Before the use of fire-arms there was infinitely more scope for personal valour than in the modern battles. Id. The same great man hath sworn to make us swallow his coin in fire-balls. Swift. When you are ordered to stir up the fire, clean away the ashes from betwixt the bars with the fire Id. Moore's Fables. BOOKSELLER. The monsters of your Botanic Garden are as surprising as the bulls with brazen feet, and the fire-breathing dragons, which guarded the Darwin. Hesperian fruit. If bleak and barren Scotia's hills arise; There plague and poison, lust and rapine grow; Here peaceful are the vales, and pure the skies, And freedom fires the soul, and sparkles in the eyes. Beattie. Each at their departure took away a greater or less fire-brand, and the remains were scattered to the wind, which was to drive away every evil as it disBrand's Antiquities. persed the ashes. FIRE. Under this popular name for what is now more usually treated in works of science under the titles of caloric, heat, or combustion, we may still classify a few exploded speculations, important only for the names attached to them. The opinions of the ancients respecting fire were various and fanciful. Ignorant of the leading facts which a theory is required to account for, and unassisted by experiments or tools, they generally made use of words which conveyed no definite ideas. They called it an active fermentation, an intestine motion, a repulsive agent, and so forth; but no real attempt towards a rational investigation is to be found in their works. And, though some of their assertions seem to coincide with the more rational modern theories, yet that apparent coincidence must be considered as being accidental; for it is not grounded upon any regular reasoning. It must be acknowledged, however, that almost all the opinions, either ancient or modern, respecting fire, may be divided into two classes; for some of them asserted that fire was nothing more than a violent agitation, in some unknown manner, of the parts of burning bodies; whilst others attributed it to something peculiar, and sui generis, which either existed in all combustible bodies, or was communicated to them. The former, which is called the mechanical hypothesis, was believed and maintained by the most able philosophers of much earlier and much more enlightened times. The celebrated philosophers of the sixteenth century, Bacon, Boyle, and Newton, were of opinion that fire was no distinct substance from other bodies, but that it consisted entirely in the violent motion of the parts of any body. As no motion, however, can be produced without a cause, they were obliged to have recourse to a mechanical force or impulse as the ultimate cause of fire in all cases. Thus Boyle tells us, that when a piece of iron becomes hot by hammering, there is nothing to make it so, except the forcible motion of the hammer impressing a vehement and variously determined agitation on the small parts of the iron.' Bacon defines heat, which he makes synonymous with fire, to be an expansive undulatory motion in the minute particles of a body, whereby they tend with some rapidity from a centre towards a circumference, and at the same time a little upwards. Isaac Newton said nothing positive upon the subject; but conjectured that gross bodies and light might be convertible into one another; and that great bodies, of the size of our earth, when violently heated, might continue and increase their heat by the mutual action and re-action of their parts. But while the mechanical philosophers thus endeavoured to account for the phenomena of fire, upon the same principles which they judged sufficient to explain those of the universe in general, the chemists as strenuously asserted, that fire was a fluid of a certain kind, distinct from all others, and universally present throughout the whole globe. Boerhaave particularly maintained this doctrine; and in support of it argued, that steel and flint would strike fire, and produce the very same degree of heat in Nova Zembla, which they would do under the equator. Other arguments were drawn from the increased weight of metalline calces, which they supposed to proceed from the fixing of the element of fire in the substance whose weight was thus increased. By these experiments Mr. Boyle himself seems to have been staggered: as Sir he published a treatise on the possibility of making fire and flame ponderable; though this was directly contrary to his own principles already quoted. For a long time, however, the matter was most violently disputed; and the mechanical philosophers, though their arguments were equally inconclusive with those of their adversaries, at last prevailed, through the prejudice in favor of Sir Isaac Newton, who, indeed, had scarcely taken any active part in the contest. The first of the chemists who attempted to form chemistry into a regular system, was John Joachim Becher; but the famous George Ernest Stahl (who was born in the year 1660, and died in the year 1734), by following Becher's plan, continued to raise the edifice, endeavouring to collect the principal facts then known into a coherent system, by connecting them by means of general principles. This intelligent man, amongst other improvements, formed the famous phlogistic theory of fire (see the article COMBUSTION), which was almost universally adopted, notwithstanding its insufficiency to account for some of the most essential phenomena of combustion. This theory continued in vogue until towards the close of the last century. The experiments on which the modern theory of combustion was first developed were those of Dr. Black, concerning what he called latent heat; on which some other names, such as absolute heat, specific fire, &c., have been bestowed. See CHEMISTRY. From these discoveries it appeared that fire may exist in bodies in such a manner as not to discover itself in any other way than by its action upon the minute parts of the body; but that suddenly this action may be changed in such a manner as no longer to be directed upon the particles of the body itself, but upon external objects: in which case we then perceive its action by our sense of feeling, or discover it by the thermometer, and call it sensible heat. It is certain, from the experiments just mentioned, that fire may exist in substances actually cold to the touch. From this discovery made by Dr. Black, along with many others in electricity, and recorded at length in various articles of this work, it is now almost universally allowed that fire is a distinct fluid, capable of being transferred from one body to another. But when this was discovered, another question no less perplexing occurred, viz. what kind of a fluid it was? or whether it bears any analogy to those with which we are better acquainted? Here we find two fluids, viz. the solar light, and the electric matter, both of which occasionally act as fire, and which therefore seem likely to be the same. See ELECTRICITY. By the vulgar, indeed, the matter has long ago been determined, and the rays of the sun as well as the electrical fluid have been promiscuously denominated elementary fire. Philosophers, however, have withheld their assent. The most strange suppositions have been made concerning the nature of both these fluids; and on the most slender grounds, or rather on no grounds at all, they have been supposed to be phologiston itself, or to contain a large proportion of it. Mr. Scheele went so far in this way as to form an hypothesis, which he endeavoured to support by some experiments, that fire is composed of dephlogisticated air and phlogiston. But it is now ascertained beyond dispute, that the result of such a combination is not fire, but fixed air: so that this hypothesis would have been altogether untenable, even though this discovery had not been made; because the dephlogisticated air itself is not a simple but a compound substance; and in all cases of combustion the one part of the air is separated from the other. It was long ago observed by Sir Isaac Newton, that heat was certainly conveyed by a medium more subtile than common air; because two thermometers, one included in the vacuum of an air-pump, the other placed in the open air, at an equal distance from the fire, would grow equally hot in nearly the same time. The consequence of this, had he pursued the thought, was, that fire itself was equally present in all places, and as active where there was no terrestrial matter as where there was. New improvements in the air-pump have enabled succeeding philosophers to make more perfect vacuums, such as it has been supposed even the electric matter cannot pass through. It is not to be doubted, however, that even there the thermometer would be heated by a fire as well as in the open air. See HEAT and COMBUSTION. The word fire has also been used both figuratively and incorrectly. The allegorical expressions, of the fire of the imagination, the fire of youth, the fire of contention, and so forth, do not fall under the cognizance of natural philosophy, but the scientific use of that word for expressing heat without light, or light without heat, or lastly, things which have neither heat nor light, is in want of correction. Thus, phosphorescent substances, like certain pieces of decayed wood, fish, &c., are frequently said to be on fire, whereas they are not attended with any degree of heat. Also the heat of fermenting substances, and of other kinds of chemical combinations, has often been called their fire. FIRE, St. ANTHONY'S. Erysipelas was first so called, it seems, in the south of France, in the twelfth century, where, and when, this disorder was exceedingly prevalent, from the success of the monks of St. Anthony (whose profession it was to attend the sick, and who therefore carried the figure of a crutch upon the left shoulder) in curing it. They made great use of lard in these cures, hence their pigs were allowed to range free through the neighbouring grounds; and that they might be distinguished from other pigs, bells were hung round their necks. These circumstances account for the figure of St. Anthony, the Egyptian hermit of the fourth century, being represented with the pig, the bell, and the letter tau upon his shoulder. Paquot in Molanum, de Imaginibus. FIRE, in theology. God has made several revelations of Himself under the appearance of fire: He appeared to Moses under the form of a fire burning in a bush; the Holy Ghost descended on the apostles in tongues of fire; and the camp of the Israelites was guided and conducted in the night-time by a pillar of fire. The Jews kept up the holy fire in the temple. This holy fire descended from heaven, first upon the altar in the tabernacle, at the consecration of Aaron and his sons to the priesthood, Lev. ix. 24. It afterwards descended anew on the altar in the temple of Solomon, at the consecration of that temple, 2 Chron. vii. 1. There it was constantly maintained by the priest, day and night, without suffering it ever to go out; and with this all the sacrifices were offered that required fire. This fire, according to some of the Jewish writers, was extinguished in the days of Manasseh; but the more general opinion among them is, that it continued till the destruction of the temple by the Chaldeans; after that it was never more restored; but instead of it they had only common fire in the second temple. The Chaldeans had a high veneration for fire, which they accounted a divinity; and in the province of Babylon there was a city consecrated to this usage, which was called the city of Ur, or of Fire. The Persians also adored God under the image or representation of fire, because it is fire that gives motion to every thing in nature. They had temples, which they called 'Pyræa,' fire temples, set apart solely for the preservation of the sacred fire. They are said to have in that empire fires still subsisting, which have burnt many thousand years. The worship of the goddess Vesta (see VESTA) and of fire was brought into Italy by Æneas and the other Trojans, who landed there; but the Phrygians themselves had received it from the eastern nations. Fire was held in religious veneration among the Gauls; and similar sentiments and practices have prevailed in several countries of America. Vulcan was worshipped among the ancients, and particularly the Egyptians, as the inventor of Fire; and Boerhaave has made it highly probable, that the Vulcan of the heathens was the Tubal-Cain of the Hebrews, the first who appears to have known the use of fire, and to have applied it in the fusion of metals and other preparations of chemistry. See PROMETHEUS. FIRE, in theology, is frequently understood of the punishment of the wicked after death. See HELL. FIRE, DIVINATION BY. See PYROMANCY. FIRE-ARROW, in naval artillery, is a small iron dart furnished with springs and bars, together with a match impregnated with sulphur and powder, which is wound about its shaft. It is intended to fire the sails of the enemy, and is for this purpose discharged from a musquetoon or swivel gun. The match being kindled by the explosion, communicates the flame to the sail against which it is directed, where the arrow is fastened by means of its bars and springs. This weapon is peculiar to hot climates, particularly the West Indies, where the sails being extremely dry by reason of the great heats, they instantly take fire, and of course set fire to the rigging, masts, and vessel. tween the troughs in the fire-room. The inside chambers should not be less than twenty-one inches, and thirty inches is sufficient for their length. The bottom parts are first well stored with short double-dipped reeds placed upright; and the remaining vacancy is filled with firebarrel composition well mixed and melted, and then poured over them. The composition used for this purpose is a mass of sulphur, pitch, tar, and tallow. There are five holes, of threefourths of an inch in diameter and three inches deep, formed in the top of the composition while warm; one being in the centre, and the other four at equal distances round the sides of the barrel. When the composition is cold and hard, the barrel is primed by filling those holes with fuse-composition, which is firmly driven into them, so as to leave a little vacancy at the top to admit a strand of quick-match twice doubled. The centre hole contains two strands at their whole length, and every strand must be driven home with mealed powder. The loose ends of the quick-match being then laid within the barrel, the whole is covered with a dipped curtain, fastened on with a hoop that slips over the head of the barrel, to which it is nailed. The barrels should be made very strong, not only to support the weight of the composition before firing, when they are moved or carried from place to place, but to keep together whilst burning: for if the staves are too light and thin, so as to burn very soon, the remaining composition will tumble out and be dissipated, and the intention of the barrels, to carry the flame aloft, will be frustrated. The curtain is a piece of coarse canvas, nearly a yard in breadth and length, thickened with melted composition, and covered with saw-dust on both sides. FIRE-BAVINS, OF FASCINES, are made of birchheath, or other brush wood, which is tough and readily kindled. They are usually two or three feet long, and have all their bush-ends lying one way, the other ends being tied together with small cords. They are dipped in the composition at the bush-ends, whose branches are afterwards confined by the hand, to prevent them from breaking off by moving about; and also to make them burn more fiercely. They are then sprinkled with sulphur. FIRE-COCKS. Church-wardens in London and within the bills of mortality, are to fix fire-cocks at proper distances in the streets, and keep a large engine and hand-engine for extinguishing fire, under the penalty of £10 by statute 6 Ann. c. 31. On the breaking out of any fire in London or Westminster, the constables and beadles of parishes shall repair to the place with their staves, and assist in extinguishing it, and cause the people to work for that end, &c. Rewards for assistance are payable to the first turncock 10s. To the first engine not exceeding 30s.The second not exceeding 20s.-The third 10s.— To be paid by the churchwardens or overseers, FIRE-BALL, in artillery. See BALL. article. FIRE-BARRELS, a sort of small barrels used for fire-ships, of a cylindrical form, as best adapted to contain the reeds with which they are filled, and more convenient for stowing be or justice of the peace. The churchwardens, &c., to be repaid by the inhabitant if the fire begins in a chimney. The FIRE ENGINE is an apparatus of compara tively modern invention, although the forcing pump, of which it is an application, is more than 2000 years old. There are laws still unrepealed which make it penal for persons to be unprovided with 'hand squirts' for the purpose of extinguishing fires, and the rude contrivances that were employed for that purpose in the last century must still be in the recollection of many of our readers. The apparatus for extinguishing fires, contrived by Mr. Newsham is exceedingly simple in the arrangement of its parts, and, as such, appears best calculated to explain the construction of this important engine. It is shown at fig. 1, plate I. HYDRAULICS, and consists of a cistern A B, about three times as long as it is broad, made of thick oaken planks, the joints of which are lined with sheet copper, and easily moveable by means of a pole and cross bar C in the fore part of the engine, which is so contrived as to slide back under the cover of the cistern, and on four solid wheels, two of which are seen at D and E. The hind axle-tree, to which the wheel E and its opposite are fixed, are fastened across under the bottom of the cistern; but the fore axle-tree, bearing the wheel D, &c., is put on a strong pin or bolt, strongly fastened in a horizontal situation in the middle of the front of the bottom of the cistern, by which contrivance the two fore wheels and the axle-tree have a circular motion round the bolt, so that the engine may stand as firm on rough or sloping ground as if it was level. Upon the ground next to the hind part of the engine may be seen a leathern pipe F, one end of which may be screwed on and off upon occasion to a brass cock at the lower end of the cistern: the other end is immersed in the water, supplied by a pond, fire-plug, &c., and the pipe becomes a sucking pipe for furnishing the pumps of the engine by its working, without pouring water into the cistern. To the hind part of the cistern is fastened a wooden trough G, with a copper grate for keeping out stones, sand, and dirt, through which the cistern is supplied with water when the sucking pipe cannot be used. The fore part of the cistern is also separated from the rest of its cavity by another copper grate, through which water may be poured into the cistern. Those that work the pumps of this engine move the handles visible at the long sides up and down, and are assisted by others who stand on two suspended treadles; throwing their weight alternately on each of them, and keeping themselves steady by taking hold of two round horizontal rails, H, I, framed into four vertical stands, which reach to the bottom of the cistern, and are well secured to its sides. Over the hind trough there is an iron handle or key K, serving to open or shut a cock placed under it on the bottom of the cistern. L is an inverted pyramidal box or case which preserves the pumps and air-vessels from damage, and also supports a wooden frame M, on which stands a man, who, by raising or depressing, and turning about the spout N, directs the stream of water as occasion requires. This spout is made of two pieces of brass pipe, each of which has an elbow; the lower is screwed over the upper end T of the pipe that goes through the air-vessel, and the Be upper part screws on to the lower by a screw of several threads, so truly turned as to be water tight in every situation. The conic form of the spouting-pipe serves for wire-drawing the water on its passage through it, which occasions a friction that produces such a velocity of the jet as to render it capable of breaking windows, &c., whilst the valves and leathern pipes of the engines have sufficient water-way to supply the jet in its greatest velocity. Leathern pipes of considerable length may be screwed at one end of the nozle of the engine, and furnished at the other end with a wooden or brass pipe for guiding the water into the inner apartments of houses, &c. tween the pyramidal box L, and the fore-end of the engine, there is a strong iron bar O, lying in a horizontal position over the middle of the cistern and playing in brasses supported by two wooden stands; one of which, P, is placed between the two fore-stands of the upper rails, and the other is hid in the enclosure over the hind part. Upon proper squares of this bar are fitted, one near each end, two strong cross bars, which take hold of the long wooden cylindrical handles, by means of which the engine is worked; and the treadles by which they are assisted are suspended at each end by chains in the form of a watchchain, and receive their motion jointly with the handles that are on the same side, by means of two circular sectors of iron fastened together, and fixed upon proper squares of the middle horizontal bar; the two fore ones may be seen at Q; the two hind ones, represented on a large scale in fig. 2, differ from the former only in thickness; for the fore sectors are made to carry only one chain each fastened by one end to their upper part, and by the lower end to the treadles; whereas the sole of the two hind sectors is wide enough to carry two chains each; one set fastened like those of the fore ones for the motion of the treadles and the other two chains are fastened by their lower ends to the lower part of these sectors, and by their upper ends to the top of the piston bars, in order to give them motion. See fig. 2, in which the hind sectors and their apparatus are represented as they would appear to a person standing betweeen the two fore-wheels, and looking at the hind part of the engine. The square over the letter A is the section of the middle bar, on which, right over the two barrels, are placed the two sectors BCA and DEA, forged together. EGHK and fghk are the two piston-rods; and the openings between the letters G, H, and g, h, are the spaces through which the hind parts of the two treadles pass. L and M represent two strong studs rivetted on the other side of the bars on which they are placed; and to each of these is fastened a chain like a watch-chain, fixed by their upper ends to the upper extremities D and B of the iron sectors by which they are drawn up and down alternately. These sectors give also an alternate motion up and down to the piston-rods, by means of two other chains left white in the figure, in order to distinguish them from the others: these are fastened by their lower ends to the lower extremities of the sectors E and C, and their upper ends, terminating in a male screw, are made tight to the piston-rods at I and F, by two nuts. The shape of the piston-rods, and the size and situation of the chains that give them motion, are so contrived, that the vertical axis of the pistons is exactly in the middle of the breadth of the perpendicular part of the chains, and the upper part of the piston-rod taken together. PQ represents one of the two cross bars through the ends of which pass the long handles to which the men apply their hands when they work the engine; these cross bars are fitted on the middle bar at some distance from the sectors. The other parts of this useful engine may be understood by the help of fig. 3, which represents a vertical section taken through the middle line of the hind part of the engine, as also the section of the air-vessel, and that of one of the barrels, and likewise the profiles of the hind sectors, and of several other parts. AB is the section of the bottom of the cistern, and C that of the hind most axle-tree. DE is the vertical section of a strong piece of cast brass or hard metal so worked as to have a hollow in it, represented by the white part, and fixed to the bottom of the cistern: this reaches from the opening D through the cock W, and afterwards divides itself into two branches, so as to open under the two barrels; one of these branches is exhibited in the figure and the other is exactly behind this. Through this channel, which may be called the sucking-piece, water is conveyed to the pumps by the pressure of the atmosphere, either from the cistern itself, or from any place at a distance, by means of a leathern pipe, F. fig. 4, which screws on to the suckingpiece at D, fig. 3, under the hind trough Z, the grate of which is represented by the horizontal strokes. FG represents the vertical section of another piece of cast brass or hard metal that may be called the communication-piece, having two hollows for conveying the water from under the two pistons to the two openings of the flanch of the air-vessel; one of these hollows appears in the figure; the other lies exactly behind this, though not in a parallel direction. Between the section of the sucking-piece D E, and that of the communication-piece FG, may be observed the section of one of the plates of leather, which makes all tight, and forms one of the two sucking-valves, of which there is another just behind this under the other barrel. RST is the section of the copper air-vessel, and TV that of the conduit-pipe; this vessel is screwed on to the hind part of the communication-piece, and at top is fastened by a collar of iron to a cross piece of timber. Between the flanch of the air-vessel and the communication-piece may be observed the section of one of the plates of leather, making all tight, and screwing one of the two forcing valves, of which there is another just behind this, exactly over the other opening of the communication from the air-vessel. These valves are loaded with a lump of cast iron or lead, having a tail or teat let through the flap of the valve and crosspinned under it; and it is to be observed that, though both the valves are represented open in the figure, they are never both open at the same time; for when the engine is not at work they are closed down by the weights on their upper surfaces; and, when the engine works, two are shut, and the other two are open alternately by the motion of the pistons and the action of the atmosphere, together with the re-action of the air contained in the air-vessel. HI is the section of one of the barrels of the two pumps, which are both sucking and forcing, as is evident from the position of the valves and the structure of the pistons, each of which is composed of two iron plates, of two wooden trenchers, and of two flat pieces of leather turning one up and the other down. LK represents one of the piston-rods edge-wise, behind which is one of the chains, the top screw of which, K, can only be seen. M is the end of the middle bar, and N a section of the hindmost of the two middle stands which support the middle bar. The principle on which the common engine acts, so as to produce a continued stream, is obvious; the water being driven into the airvessel, as in the operation of common sucking and forcing pumps, will compress the air contained in it, and proportionably increase its spring, since the force of the air's spring will always be inversely as the space which it possesses; therefore, when the air-vessel is half filled with water, the spring of the included air, which in its original state counterbalanced the pressure of the atmosphere, being now compressed into half the space, will be equal to twice the pressure of the atmosphere; and, by its action on the subjacent water, will cause it to rise through the conduit-pipe, and to play a jet of thirty-two or thirty-three feet high, abating the effect of friction. When the air-vessel is twothirds full of water, the space which the air occupies is only one-third of its first space; therefore its spring, being three times as great as that of the coinmon air, will project the water with twice the force of the atmosphere, or to the height of sixty-four or sixty-six feet. In the same manner, when the air-vessel is three-fourths full of water, the air will be compressed into one-fourth of its original space, and cause the water to ascend in air with the force of three atmospheres, or to the height of ninety-six or ninety-nine feet, &c., as in the following table. |