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or decreased, according to the purpose to which the machine isapplied. As soon as the larger wheel is fixed, the smaller one isplaced within it, and is fastened on an axis, so as to turn in a rota-tive direction round its centre ; the smaller wheel being thus sta-tioned, may be occasionally fixed, and the larger one moved inthe same direction round the smaller one: the former of these,however, is preferable in all cases. At each end of the largerwheel there is a flanch, to which are screwed two plates, or capsinclosing its ends, and into which the extremities of the smallerwheel are inserted, so as to render the junction water-tight:through these caps passes the axis of the inner cylinder, in orderto communicate motion from without. Or the inner wheel maybe applied so as to give motion, by its external end or ends, toany other engine or machine connected with it. These are theComponent parts of Messrs. Graham's and Dickenson’s patent en-gines ; fora more particular account of which, we refer the readerto the 2d vol. of the Repertory of Arts and Manufactures, wherehe will find a minute account of the machinery, and the ef-fects it is calculated to produce. A patent was likewise grantedin December 171)2, to Mr. Charles Simpkin, of Oxford-street,engine-maker; for his improvements in ail kinds of machines forextinguishing fire. This invention consists in exploding or re-moving the valves both from that part of the cylinder, where thevacuum is made by the piston or fly, and from beneath the air-vessel ; and in making use of valves, by the application of certainfiltering chambers, with partitions or divisions, to preserve theeffect of the valves, during the use of any improper fluid. Thesefiltering chambers are to be placed between the drawing valves,and the strainer in common use, on the suction-pipe. The par-titions in the chambers may be of fine wire-work, or of any othersubstitute, that will act as a first and second filtration in the cham-ber. The design of this invention is, to render the valves morefree of access, and to prevent the necessity of opening any otherparts of the engine, except the chambers containing the valves;by which means the effect of the machine is increased, and con-sequently the fire may be more easily extinguished. 9 o thesedifferent contrivances we shall add the American lire engine, ofwhich we have given an accurate engraving, it was invented byMr. Benjamin Dearborn, who communicated it to the AmericanAcademy of Arts and Sciences , from whose Memoirs for 1794,we extract the following description. In fig. 3, Plate LX X, AB,and C D, are the edges of two planks, confined together by fourbolts .—a b, and cd, are two cylindrical barrels, in each of whicha piston, with a valve, is fastened to the spear e, and is moved upand down alternately by the motion of the arms If if. Beneatheach barrel a hole is made through the plank AB, which is coveredwith a valve. The arms E E, are suspended on the common cen-tre/; there are also arms parallel to these on the opposite side ;gg are the ends of handles which are fastened across the ends ofthe arms. At h, a boll goes across, from arm to arm, to whichthe piecei£, is affixed, and on which it plays; the lower end ofthis piece is fastened to the top of the spear e. —G, l,f, is a stand-ard for the purpose of supporting the arms, to which there is acorrespondent one on the opposite side ; both are notched into theedges of the planks, where they are secured by a holt, whichpasses through them at /, and lias a nut or fore-lock on the oppo-site side. Ill, III, are square braces, answering the purpose ofducts, through which the water ascends from the barrels, passingthrough the plank at vi. KL, K L, are irons in the form of astaple, in order to confine the braces : the lower ends of theseirons meet, and are secured by a bolt passing through them, andM Nf, no, which is a piece that goes up through a mortice in thecentre of the planks. This piece is square from the lower end,till it reaches the top of the braces; whence they becomecylindrical to die top, the upper end being perforated sufficient!)low down, in order to communicate with the braces. O, P, is aniron ring, that surrounds the tube, and has two shanks which as-cend through the head, which screws oil the top at p, </;—r, ,?,is aferule nailed round the tube. Fig. 4, is the same engine; thearms and standards being taken off, in order to delineate moreclearly the mode of securing the braces; an object which is com-pletely effected by a wedge driven into the mortice a: beneaththe upper plank b, is a hole for admitting a passage to the holt,which secures tiie standards. In this figure, a side-view of thehead is given, with the pipe in a perpendicular direction. The

machine is confined within a box, set on wheels, as in the commonfire-engines. The whole is made of wood, excepting the spearsof the pumps, and a few holts, &c. The advantages of this ma-chine are, that it can be made in any place where common pumpsare manufactured; the interior work will not exceed one-fourthof the price of those which are constructed on the usual plan ; andthat they are incomparably more easy to work, than tile commonones ; circumstances which strongly recommended the Americanfire-engine to the attention of the public. The fire-engine is in allcases, a very ineffectual machine, where it cannot supply a very-large quantity of water in proportion to the fire to be extinguished.On tiie breaking out of a lire, all constables are enjoined, by se-veral acts of parliament, to repair to tiie place ; to use every ex-ertion for extinguishing the flames; and to cause the people towork, &c. By the 10 Ann. c. 14, no action shall tie commencedagainst any person in whose house or chamber a lire shall breakout accidentally; but, if such fire happen through the negligenceof any servant, the latter incurs a penalty of 100/. to he distri-buted among the sufferers; and in default of payment, lie is to lieimprisoned for 18 months, during which time ho is to lie kept tohard labour. Tiie wilful setting of fire to any house, out-house,or other building, is felony without benefit of clergy.

Eire-Arms are those which are charged] with powder amiball ; such as musquets, carbines, pistols, cannons, &c. In De-cember 1780, a patent was granted to Mr. John Aitken, of Edin-burgh , surgeon, for his invention of a new method of loading fire-arms, of whatever dimensions or forms, with two or more chargesof powder and ball, and of discharging them in -succession, by lirecommunicated through correspondent perforations, or touch-holes. This consists in lodging several charges of powder and shotin tiie fire-arms, whether cylindrical, conical, chambered, orotherwise ; tiie hindmost extremity, or breech, being closed,while the anterior one, or muzzle, is open. The extension of thefire, in a posterior direction from the charge next the muzzle thatis first inflamed, is intercepted by intermedia placed between theseveral charges, which are firmly rammed about or above the shot;and which are formed of any substance that possesses sufficient re-sistance, is compact, incombustible, and properly shaped. Inthe smaller fire-arms, namely pistols, musquets, blunderbusses,&c. tiie patentee chiefly employs leather, or other thick Stulls. Inthe larger ones, such as camions, mortars, &c. he makes use ofvarious pastes, as being more commodious, and more easily pro-cured. The charges are ignited through touch-holes by the lock,or match, as occasion may demand, according to the size andcondition of the tube.

Eire-Arrow, in naval artillery, is a small iron dart furnishedwith springs and bars, together with a match impregnated with sul-phur and powder, which is wound about its shaft. It is intendedto fire the sails of the enemy, and it is for this purpose dischargedfrom a musquetoon or swivel gun. The match being kindledby the explosion, communicates the flame to the sail against whichit is directed, where the arrow is fastened by means of its bars andsprings. This weapon is peculiar to hot climates, particularlythe West Indies , where tiie sails being extremely drv by reasonof tiie great heats, they instantly take lire, and of course set lireto the rigging, masts, and vessel.

Firf.-Bali., in artillery, a composition of powder, sulphur, salt-petre, pitch, &c. about the bigness of a hand-grenade, coated overwith liux, and primed with the slow composition of a fuze. Thisis to lie thrown into tiie enemy’s works in the night-time, to dis-cover where they are ; or to lire houses, galleries, or blinds of thebesiegers; but they are then armed with spikes or hooks of iron,that they roll not off, but stick or hang where they are desired tohave any effect. Sec Ball.

Fire-Eater. A great number of mountebanks have attractedthe attention and wonder of the public by eating fire, walkingon fire, washing their hands in melted lead, and the like tricks.The most celebrated of these was our countryman Richardson,much talked of abroad, llis secret, as related in the Journal desSijavaiis, of 1680, consisted in a pure spirit of sulphur, wherewithlie rubbed his hands, and tiie parts that were to touch the fire ;wRich burning and cauterizing tiie epidermis, hardened and ena-bled the skin to resist tiie fire. Indeed this is no new tiling:Amh. Pare assures us that lie had tried it on himself: that alterwashing tiie hands in urine, and with an imguentum aureum, one

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