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mortars, and small-arms presents itself; but in the of Ctesias and Ælian, to have also possessed an infancy of the invention, and amid the obscurity unquenchable fire similar to that employed later by enshrouding it, we can only seek to inquire into the the Greeks. Passing from these very early times, origin of firearms generally.
in which there is reason to believe that some sort of The invention of gunpowder bears so directly great gun was employed, we come to the comparaupon the gradual introduction of firearms, that it tively recent date, 1200 A.D., when their use is will be well to consider the two discoveries concur- established beyond a doubt, for Chaséd, the Hindu rently. The widely prevalent notion that gun. bard, writes (in stanza 257) that the culivers and powder was the invention of Friar Bacon, and that cannons made a loud report when they were fired cannon were first used by Edward III. of England, off, and that the noise of the ball was heard at the must be at once discarded. It is certain that distance of about ten coss, which is more than threegunpowder differed in no conspicuous degree from quarters of a mile. In 1258, the vizir of the king of the Greek fire of the Byzantine emperors, nor from Delhi went forth to meet the ambassador of Hulaku, the terrestrial thunder of China and India, where it the grandson of Genghis Khan, with 3000 carriages had been known for many centuries before the of fireworks (in the sense of weapons, probably a chivalry of Europe began to fall beneath its level sort of rude muskets). In 1368, 300 gun-carriages ling power.
were captured by Muhammed Shah Bahmiani. The Nitre,' says Sir George Staunton, 'is the natural use of cannon båd so far advanced in India by 1482, and daily produce of China and India ; and there, that they were even used for naval purposes ; shells accordingly, the knowledge of gunpowder seems to having been employed two years earlier by the be coeval with that of the most distant historic sovereign of Guzerat. In 1500, the Portuguese had events.' The earlier Arab historians call saltpetre matchlockmen to contend with, as well as heavy *Chinese snow' and Chinese salt;' and the most ordnance. Pigafetta, in 1511, found the town of ancient records of China itself shew that, when Borneo defended by 62 pieces of cannon mounted on they were written, fireworks were well known, the walls. So much for the antiquity, and appar. several hundred years before the Christian era. ently common use of firearms in China and India, From these and other circumstances, it is indu- at times long antecedent to any knowledge of them bitable that gunpowder was used by the Chinese in Europe, and during the period at which they as an explosive compound in pre-historic times; were scarcely developed in an effectual degree. when they first discovered or applied its power as a Most of the pieces discovered in India, and supposed propellant, is less easily determined. There is an to be of early manufacture, are composed of parallel account of a bamboo tube being used, from which iron bars welded together, and very often they had the impetuous dart' was hurled a distance of 100 a movable breech-piece. feet: this was at a very early period, but it is diffi The knowledge of gunpowder and firearms may cult to say precisely when. It is recorded, however, be presumed to have extended in a westerly direc. that in 618 B.C., during the Taing-off dynasty, a tion through the Arabs, whom we find using them cannon was employed, Learing the inscription : 'I possibly in 711 A. D., under the name of manjaniks, hurl death to the traitor, and extermination to and certainly very early in the 14th century. The the rebel.' This must almost necessarily have been Byzantine emperor, Leo, introduced ‘fire-tubes' of metal. We have also curious evidence in regard between 890 and 911, for use in connection with, to the armament of the Great Wall; for Captain Greek fire; and there can be little doubt that these Parish, who accompanied Lord Macartney's mission, were a species of cannon, probably of small bore. reported that “the soles of the embrasures were in Spain, both Moors and Christians used artillery pierced with small holes, similar to those used in as early as the 12th century. Europe for the reception of the swivels of wall Friar Bacon was conspicuous among his contem. pieces. The holes appear to be part of the original poraries for his general learning, and we have nc construction of the wall, and it seems difficult to evidence to shew whether he discovered the ingreassign to them any other purpose than that of dients of gunpowder independently of foreign aid, resistance to the recoil of firearms.' If this surmise or whether he derived the knowledge from sorao be correct, the use of jingalls would be carried back ancient manuscripts; the latter, however, seems to three centuries at least before the Christian era. the more likely conclusion, as Sir F. Palgrave Stone mortars, throwing missiles of 12 lb. to a brought to light in the Bodleian Library a letter distance of 300 paces, are particularly mentioned from a Spanish friar, Brother Ferrarius, who was as having been employed in 757 A. D. by Thang's a contemporary of Bacon, in which the materials of army; and in 1232 A.D., it is incontestable that Greek fire are detailed, differing only in proportions, the Chinese besieged in Caïfong-fou used cannon and in these but slightly, from real gunpowder. against their Mongol enemies. Thus, the Chinese That the latter was identified of old with Greek must be allowed to have established their claim fire, is shewn by the name . Crake,' applied to the to an early practical knowledge of gunpowder and first cannon used. This word, which still survives its effects.
in.cracker,' is pointed out by Sir F. Palgrava to It seems likely, however, that the principles of be nothing more than a Norman corruption of firearms reached Europe from India rather than Grec.' Bacon's announcement dates from 1216; China, and that country has equal, if not superior, but the powder of his time, as made in the West, claims to the first acquaintance with the art. The was not readily explosive, since the materials were ancient Sanscrit writings appear to point very but roughly cleared of impurities, and then mixed plainly to the operation of some primitive sort of together on a slab; and probably little use could cannon, when, in recording the wars of the Egyp- be made of it as a propellant until the process of tian Hercules in India, it is stated that the sages granulating had been introduced by Bertholdus remained unconcerned spectators of the attack on Schwartz in 1320. Immediately after this distheir stronghold, till an assault was attempted, when covery, cannon of small size appeared in the armoury they repulsed it with whirlwinds and thunders, of almost every state, as if their use had been hurling destruction on the invaders; and a Greek known previously, although no practical effect had historian of Alexander's campaign testifies that the been given to the knowledge, on account of the Hindús had the means of discharging flames and badness of the powder manufactured. These cannou missiles on their enemies from a distance.
generally consisted of a smaller barrel or chamber These Indian philosophers seem, from the writings to receive the charge, which fitted into a larges
one containing the projectile (see fig. 1). It may hand-weapons, but for their cumbrous and heavy be safely assumed that these weapons, if terrifying workmanship, which necessitated small carriages from their noise, were tolerably harmless—at least Arms of this description are doubtless thosa
to the enemy-in their
and cannon for the defence
of its villages. In 1327, From the Santini Manuscripts. of war against the Scotch;
Edward III. used 'crakeys in 1339, ten cannons were employed in the siege of Cambray. By 1346, various improvements had been made; and we find in the same year the consuls of Bruges witnessing experiments by one Peter, a tinman, who had constructed a cannon with a square bore, to throw a cubical shot of about eleven pounds; his bolt passed both walls of the town, and unfortunately killed a man on the other side. We have the authority of Villani for believing that Edward III. had three cannon at Fig. 2, from the Chroniques de St Denis, Fourteento Crécy; but the cannon then made were, from the Century. Fig. 3, Bombard of the Fifteenth Century, little knowledge of casting, limited to about the from Froissart. Fig. 4, Cannon of the Fifteenth size of modern duck-guns, and, as has been re
Century, from Les Vigiles de Charles VII. marked, three very inferior muskets could have had but little to do with putting 50,000 men to flight.
referred to as having been brought by Richard IL Up to this time, European ordnance had been to the siege of St Malo, to the number of 400 kept back by the rarity and high prices of sulphur, pieces, where they are said to have kept up an saltpetre, and iron, the last having been so scarce
incessant fire day and night on the town without in England, that it was thought necessary to forbid success, its exportation by a statute of 28 Edw. ÎII. Still,
In the 15th c., armies for siege operations were crude as was their form, and small their number, usually accompanied by great and small guns, the firearms had established a firin footing in Christen- latter being intended to keep down the fire of the dom; their mission of civilisation, and, paradoxical besieged while the large bombards were being loaded, as it may appear, of humanity, had begun. With an operation requiring no small time. These guns the first killing discharge, the doom of feudalism were gradually improved, but it was not until the had gone forth. Plated armour no longer availed reign of Henry VIII. that the founders succeeded against the weapon of the peasant; and the mailed in casting iron ordnance, to the entire exclusion, chivalry, the sinews of previous battles, who had thenceforward, of cannon formed of square or trampled with their iron heels upon popular rights, rounded bars welded together. England had even no longer could carry all before them, but, like then become famous for the workmanship of its other soldiers, were now as loath to be slain ordnance. The accompanying sketch (fig. 5) of a gun by unseen foes as the veriest villein in the host. found in the wreck of the Mary Rose, which sunk at The people discovered their powers of contending with the noblesse; by degrees, they rose for liberty, and suppressed the tyrannies of the petty lords who had long held them as mere bondsmen. In war, again, as artillery became more general, so the
Fig. 5. slaughter of battles diminished, for an army outmanæuvred was an army at the enemy's mercy, Spithead in the above king's reign, will shew that a and therefore beaten; whereas, previously, in the degree of excellence had been attained in the manuhand-to-hand fights where victors and vanquished facture of artillery, little inferior to that which has mixed pell-mell in single combat, a victory could lasted till our own day, when rifled ordnance are only be really won when there were no foes left rapidly superseding cannon of smooth bores. Still, to slay. A battle as great as that at Crécy might so late as Henry's reign, although great guns were now be gained with a loss to the vanquished of not found very serviceable in siege and naval operamore than 1000 men, instead of the 30,000 who tions, where the defences of those days offered but are said to have fallen victims to the English sword a trifling resistance to their power, they appear to or bow.
have been looked upon rather as an encumbranco Dating from the reign of Edward III., the than an advantage with armies in the field. Thus employment of cannon and bonıbards in siege is attributed partly to the heavy character of the operations became more or less general. Froissart guns themselves, and especially of their carriages, records that the Black Prince took bombards, but more particularly to the badness, or rather cannon, and Greek fire to the reduction of the absence, of the necessary roads for their transport. castle of Romozantin in 1356, but it does not In 1522, it is recorded in the state papers that the appear that he availed himself of firearms at the kinges ordonauns (were unable to pass over Stanes battle of Poitiers in the same year. The bombards More towards Carlile.' seem to have been short, capacious vessels, from As time passed on, the details of the manufacture which stone balls were shot with small charges to were improved, the general principles remaining a short distance, and at considerable elevation; the same; the size of the guns increased, while the they were essentially the parents of the present proportionate weight of the carriages diminishel, bombs or mortars (see fig. 2). The cannon (canna, | limbers (q. v.) were added, and the equipage of a gun a reed), on the other hand, were, for some time at gradually perfected and lightened. With increased least, of extremely small bore, scarcely larger than calibre, to which augmented range was usually muskets of the 18th c.; they discharged leaden added, the number of cannon-at one period enoronliets, and would have probably been used as mous—taken with an army was by degrees redacod,
antil now a certain standard proportion between A gun is a frustrum of a right cone, with a artillery and infantry is ordinarily maintained. Of cylinder (bore) removed around the axis; from which course, this proportion differs with the opinions of it follows that the thickness of metal is greatest various commanders ; but the greatest modern at the breech, where has to withstand the effect generals have always acted on the maxim, that it of ignited powder in its most condensed, and thereis wasteful to send a soldier on any duty of danger fore most powerful state. Guns are first cast in which a ball can be made to perform. As a weapon loam or dry sand, then turned to the required of offence, Vauban doubted the utility of heavy shape, and lastly bored with the minutest accuracy ordinance when he applied the Ricochet (q. v.) Formerly, they were cast with the bore already system of firing. Napoleon may almost be said formed; but the direction was rarely exactly con to have won his battles by artillery, for he rarely rect, and the surface scarcely, ever strictly even. if ever brought his infantry into action except as Some additional particulars of their manufacture supports, until a way had been opened for them, will be given under GUN-FACTORIES, Royal; and
a panic caused, by the massed fire of large the science of artillery will be summarised under batteries of guns. The Duke of Wellington also | GUNNERY. devoted the greatest attention to his ordnance An article on firearms would be incomplete train; while, referring to recent events, the campaign without some allusion to the progress made in of Lord Clyde in Oude is a remarkable instance of small-arms. In the 15th c., the smallest sort of the use of artillery being pushed with abundant cannon were probably at times mounted and used as success to its greatest limit.
hand-guns. From this the step to the arquebus was Cannon of widely varying bores have at different rapid ; that weapon developed as years passed into times been cast, and the various sorts became so the clumsy matchlock; that into the firelock numerous in continental armies, as at one time to and flint-musket ; then the percussion-musket; and cause much inconvenience from the large quantities lastly, into the beautiful rifles of our own day. of ammunition which it was necessary to carry. For diminutives, small arquebuses were made to Gustavus Adolphus set the example of reducing do duty as horse-pistols ; genuine pistols succeeded his guns to a few standard calibres, and the same them; these were gradually improved and reduced improvement was immediately adopted systematic. in size, till they have culminated in the saloon ally in the French and other armies. The cannon pistol, available for a waistcoat-pocket; and the recently in use in the British army are detailed deadly revolver, which quadruples a man's defen. un ler the article CANNON; but the action of sive power. All these weapons are described under government has tended for some years to call in their respective heads-- ARQUEBUS, MATCHLOCK, all the guns which are not of a few general MUSKET, Pistol, REVOLVER, RIFLE standards, such as 6, 9, 12, 18, 24, 32, and 68 Many valuable works have been written on fire. pounders, and 8-inch guns. These, with the arms from the days of Leonardo da Vinci and various sizes of Armstrong guns, which have a Tartaglia to the present. Among those consulted special sort of ammunition, represent now nearly for this article have been Etuiles sur le Passé et all the ordnance on the British batteries. For a l'Avenir de l'Artillerie of the Emperor Napoleon more particular explanation of the several sorts of III. ; Our Engines of War, by Captain Jervis ; cannon and their parts, see GUNNERY, CANNON, Major Straith's Treatise on Artillery; General CARRONADES, HOWITZER.
Chesney On Firearms, &c. The mortar differs from all other guns in its solidity of form, its shortness, and its large bore.
FIREARMS, PROVING OF (in Law). In consu: The object is the projection of shells by a more or quence of the frequency of accidents from the less vertical fire, with the intention of breaking bursting of insufficient barrels, the legislature bag through and destroying, by weight and explosion directly, but to prevent all persons from using
interfered, not to regulate their manufacture together, roofs of magazines, public buildings, and BO on, or of sinking a shell deep into earthworks
or selling them until they have been regularly of a fortress, in which it shall explode as a most
proved in a public proof-house. The first act deadly mine. The different sorts of mortar will for this purpose, which was passed in 1813, was be described under MORTAR. The mortar arose
soon after superseded by the fuller and more naturally out of the old complete one (55 Geo. III. c. 59). By this statute, a bombard, and doubtless
fine of £20 is imposed on any person using, in any deviated by degrees more
of the progressive stages of its manufacture, any
barrel not duly proved; or any person delivering and
from the Fig. 6 shews
the same, except through a proof-house; and on any a bombard
person receiving, for the purpose of making guns, designed in the 15th house. These penalties are to be levied on convic
any barrels which have not passed through a proofcentury. In very early Fig. 6. days, we read in Arabian tion before two justices, and the like penalties on authors of a cylinder does not extend to Scotland or to Ireland, and
persons counterfeiting the proof-marks. The statute From Leonardo da Vinci.
hewn in the rock at Alexandria, and used as a mortar. Such a cylinder, îrom its operation. By 10 Geo. IV. c. 38, repeal
arms manufactured for Her Majesty, are exempted and of large size, is still to be seen at Gibraltar, ing 6 Geo. IV., the malicious and unlawful use of where it was employed in the last siege against firearms in Scotland is punishable at law. See the Spanish, when it was made to discharge
GAME. volleys of large stones, which spreading at times to a distance of 500 yards, constituted a formidable FIREBALLS are projectiles occasionally dis. means of defence,
charged from guns or mortars, for the purpose either In the British service, the calibre of solid-shot of setting fire to, or of merely illuminating some work, guns is described by tho pounds which the shot against which hostile operations are directed. The weigh; in the case of guns for hollow shot or shell, usual ingredients are—mealed powder, 2 ; saltpetre, and of mortars, by the inches in the diameter of the 11; sulphur, 1; rosin, 1 ; tarpentine, 2}; with pitch, bore. In some continental armies, the power of the tow, naphtha, &c., as circumstances dictate. The use gun is reckoned by the weight of a stone ball fitted of fireballs has, however, been in great measure to the bore.
superseded by the introduction of rockets (q. v.)
1.88 2.99 3-64
and incendiary shells (q. v.). Akin to the fireball, gaped, and was quite broiled ; then he melted was the fire-arrow of ancient warfare, which con- pitch and wax with sulphur, which he drank down sisted of tow steeped in pitch, rosin, or some inflam- as it flamed; I saw it flaming, in his mouth mable mixture, wrapped round the shaft, and fired good while; he also took up a thick piece of iron, alight among an enemy's works or troops. Greek such as laundresses use to put in their smoothing. fire was also discharged in many cases on large boxes, when it was fiery hot, held it between his Arrows surrounded by tow and shot from balistæ. teeth, then in his hand, and threw it about like a
FIREBOTE, the right of a tenant for life or stone; then he stood on a small pot, and bending years, according to English law, to cut wood on the his body, took a glowing iron with his muuta estate for the purpose of fuel. See EstoVER
from between his feet, without touching the
pot or ground with his hands; with divers other FIREBRICK. See BRICK.
prodigious feats.' About 1818, Signora Josephine FI'RECLAY is the variety of clay which is Girardelli
, who described herself as the original einployed in the construction of gas-retorts, glass. Salamander,' performed astonishing feats of this pots, tirebricks, crucibles, &c., which require to kind in London and other places in England. withstand high temperatures. It is found chiefly According to the accounts of her, “She commences in the coal measures; and the more famous kind is her performances by passing plates of red-hot iron the Stonebridge, which is found in a bed about four over her legs; she then stands with her feet naked feet thick. It also occurs largely near Glasgow, on a plate of red-hot iron, and afterwards draws the Newcastle-on-Tyne, and in Belgium and France. same plate over her hair and across her tongue,' The principal constituents of fireclay are silica and &c. About the same time appeared in Paris M. alumina, accompanied by small proportions of iron, Chaubert, whose astonishing powers of resisting lime, magnesia, water, and organic matter, as may heat attracted the attention of the National Instibe observed from the following table :
tute. Among other things performed by this person, was his going into a common baker's oven, with a leg of mutton in his hands, and remaining with
the oven closed until the mutton was completely Silica,
dressed. Another of his performances was standing Alumina, Oxide of Iron,
in a flaming tar-barrel until the whole of it was Lime,
consumed around him. He subsequently exhibited 1.915
in London. Organic Matter and Water,
Many of the feats of this kind are undoubtedly
mere tricks, or illusions, produced by sleight of Fireclay is found abundantly, near and at the There is nothing more wonderful in stuffing blazing
hand; others are capable of scientific explanation surface of the ground, and is readily reduced to tow into the mouth-a common form of inountebank powder by travelling wheels. When kneaded with water, and fashioned into vessels and other articles, tire-eating-than in eating flaming plum-pudding, it is dried, and is then generally subjected to a burn like a candle. It is also well known that the
or in dipping the finger into spirits and letting it strony heat, which drives off the water and organic tongue, or the haud dipped in water, may be rubbed with the alumina, &c., and leaves a more or less with impunity against a white-hot bar of iron; the porous material, which can withstand very high layer of vapour developed between the hot metal temperatures. The Passau crucibles are merely
and the skin prevents contact and produces coolness dried, and are not fired like Hessian crucibles and (see SPHEROIDAL CONDITION OF LIQUIDS). Such other fireclay wares. The larger the percentage the well-known power of the living body to maintain
performances as those of M. Chaubert are explained by of silica (sand) in the clay, the more refractory are its normal temperature, for a time, independently of the articles fashioned from it; and hence sand is the external teinperature (see Animal HEAT). often ailed to clay to increase its fusing-point and refractory powers; but a certain proportion
FIRE-ENGINE, a machine employed for throw. of alumina, &c., is required to serve as a flux, ing a jet of water for the purpose of extinguishing to cement and hold together the particles of sand tires. This name was formerly applied to the The proportions of sand and clay are determined steam-engine. Machines for the extinguishing of by the temperature to which the manufactured tires have been used from a very early date. They article is intended to be exposed; and the fireclay were employed by the Romans, and are referred to of crucibles or bricks, which are serviceable at å by Pliny; but he gives no account of their construccomparatively low temperature, as in the lining tion. Apollodorus, architect to the Emperor Trajan, of limekilns, would become soft, and yield in glass speaks of leathern bays, with pipes attached, from or porcelain furnaces.
which water was projected by squeezing the bags.
Hero of Alexandria, in his Treatise on Pneumatics FIREDAMP is the miners' term applied to light-written probably about 150 years before the carburetted hydrogen or coal-gas when it issues from Christian era-proposition 27, describes a inachine crevices in coal-mines. See GAS,
which he calls the siphons used in conflagrations.' FIRE-EATING,
usnally given to It consisted of two cylinders aud pistons connected a variety of feats performed by jugglers with by a reciprocating beam, which raises and lowers Anning substances, melted lend, red-hot metal, &c. the pistons alternately, and thus, with the aid of Evelyn, writing under date October 8, 1672, thus valves opening only towards the jet, projects the describes tire-eating in his day: ‘I took leave of water froin it, but not in a continuous stream, as my Lady Sunderland. She made me stay dinner the pressure ceases at each alternation of stroke. at Leicester House, and afterwards sent for The accompanying copy of Hero's diagram Richardson, the famous fire-eater. He devoured explains itself. Little or nuilding is known its to brimstone on glowing coals before us, chewing the extent to which engines of this kind were pracand swallowing them; he melted a beer-glass, and tically used. We have accounts of " instruinents for eat it quite up: then taking a live coal on his tires.' and 'water syringes useful for fires,' in the tongue, he put on it a raw oyster; the coal was building accounts of the city of Augsburg, 1518; and blown on with bellows till it Hamed and sparkled in 1657, Caspar Schott describes a fire-engine used in his mouth, and so remained till the oyster | in Nuremberg, which must have been almost
identical in construction with that described by Hero. Hero describes and figures the air-chamber as It had a water-cistern, was drawn by two horses, hollow globe or other vessel, into which if any liquid was worked by 28 men, and threw a jet of water, be poured, it will be forced aloft spontaneously
and with much violence, so as to empty the vessel though such upward motion is contrary to nature.' The globe is represented with a single piston attached for compressing the air. Thus, about 1800 years elapsed before proposition 9 and proposition 27 of this work were put together for so obvions and useful a purpose as the fire-engine, although the book was tolerably well known to the mathematicians of the period ; and when they were put together, it was probably done by a practical man, who had never heard of the name of Hero.
The more recently constructed fire-engines include contrivances for preventing the entrance of mud and gravel, and for getting readily at the valves in case of their being out of order, while the cistern is
dispensed with, a hose being carried directly to the an inch in diameter, to a height of 80 feet. It was water-supply. They are usually drawn by two or not until late in the 17th c. that the air-chamber four horses, though smaller engines are made to be and hose were added; the first being mentioned drawn by hand or by one horse. The hose is of by Perrault in 1684, and the hose and suction-pipe leather, fastened by metal rivets, instead of the being invented by Van der Heide in 1670. In sewing formerly used. In the United States, cotton England, hand-squirts were used up to the close is woven into a tube by machinery constructed for of the 16th century.
They were of brass, and the purpose. Two such tubes are fitted one within contained three or four quarts of water. Two men the other, and held together by a solution of Indiaheld the handles at the sides, while a third forced rubber, which, on consolidating, forms a water-tight ap the piston. The nozzle was dipped in a vessel layer. of water after each discharge, then raised, and the The fire-engines of the London Fire Brigade water again forced out. So clumsy an apparatus establishment have usually 7-inch barrels with could have been but of little service in the fearful 8-inch stroke, and throw about 90 gallons of water conflagrations to which our old wood-built towns per minute. Their weight, with implements, fire. were so subject
men, and driver, is about 30 cwt. These are found With the addition of the air-chamber and hose, more convenient for general purposes than larger and some improvement in the details of construc- engines, as they can be drawn at a gallop by two tion, the siphons' of Hero became the modern horses for a distance under six miles. Four horses fire-engine. The principle of the action of the air- are used for greater distances. When a large engine chamber, and of its connection with the pumps, &c., is required, two of these may be joined together, will be easily understood by the aid of the annexed and throw 180 gallons per minute. The pumps are liagram, where a represents in section a piston worked by levers, with long horizontal bars attached,
ascending, d the other to enable a number of men to work together upon piston descending, f the the same pumps. Many larger engines than these pipe or hose communicat- have been constructed, and steam has been success. ing with the water-supply, fully applied. The first application of the steam g the hose that conveys the fire-engine was made when the Argyle Rooms in issuing stream to the fire, London were burned in 1830.
Several floating bc the level of the water fire-engines for conflagrations near the Thames in the air-chamber, e the have been constructed and worked by steam; one space above filled with of these is capable of throwing 1400 gallons per
compressed air. The rising minute. A floating engine was used with consider. d piston raises the water from able effect when the Houses of Parliament were
I to fill its cylinder; the burned; but at the fire of the warehouses near descending piston forces London Bridge (1861), the fury of the combustion, the water contained in its when at its maximum height, was so great, that cylinder into the bottom the combined efforts of all the London engines, of the air-chamber, and whether worked by steam or by hand, had no thereby compresses the air perceptible effect in subduing it. For all ordinary in e. The pistons rise and fires, the hand-engines above referred to are the
descend alternately. The most useful, as they can be brought to the spot rompressed air reacts by its elasticity, and pressing and set in action immediately, whereas some time apon the surface bc, forces the water through the must always be lost in getting up the steam, and hose 9. In the space e, above be, the whole of the in bringing to the locality of the fire the larger air tlfat formerly filled the chamber is supposed to steam fire-engine. The saving of a few minutes is be compressed. Assuming this to be one-third of its often of more importance than doubling the quantity griginal bulk, its pressure will be about 45 lbs. to the of water. These more powerful engines are there. square inch, and this pressure will be continuous fore only likely to be used for great fires, where the and nearly steady, if the pumps act with sufficient smaller engines, after working for some time, are Zorce and rapidity to keep the water at that level. found to be insufficient. As air may be compressed to any extent-and its It has been questioned whether, in cases of very elasticity is increased in exactly the same proportion intense combustion, a comparatively small stream of - the force that may be stored in the compressed water has any subduing effect at all— some assert air is only limited by the force put upon the pumps, that it may even increase the conflagration. It and the strength of the apparatus.
appears that carbon, in a state of intense incandesUnder proposition 9 of the same work, in which cence, is capable of decomposing water by combining the siphons used in conflagrations are described, with its oxygen to form carbonic oxide; this gas,