MANUFACTURES

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Manufac- Who first conceived the idea of applying’ to the firetures. engine an air chamber, in which the included air, byv—compressing the water, forces it out in a continuedstream, is not known. According to a conjecture ofPerrault, Vitruvius seems to speak of a similar construc-tion ; but Perrault himself acknowledges that the ob-scure passage in question might be explained in anothermanner. The air chamber in its action has a similarityto Hero’s fountain, in which the air compressed by thewater obliges the latter to ascend.

We find no older fire engine constructed with anair chamber than that of which Perrault has given afigure and description. He says it was kept in theKing’s Library at Paris , and during fires could projectwater to a great height,- that it had only one cylinder,and yet threw out the water in one continued jet. Hementions neither its age nor the inventor; his bookwas printed in 1684. The principle of this Machine,however, seems to have been mentioned before by Mar-riotte, who, on this account, is by some considered as theinventor; but he does not appear to have had any ideaof a fire engine, at least he does not mention it.

It is certain that the air chamber, at least in Ger­ many , did not come into common use till after it wasapplied by Leupold to fire engines, a great number ofwhich he manufactured and sold. He gave an accountof it in a small Work, consisting of four sheets quarto,which was published in 1720, but at first he kept the con-struction a secret. The engines which he sold consistedof a strong copper box closely shut and well soldered.They weighed no more than sixteen pounds, occupiedlittle room, and only one cylinder, and a man with oneof them could force up the water without interruptionto the height of from twenty to thirty feet. About1725, Du Fay saw one of Leopold’s engines at Stras-burg, and discovered, by conjecture, the construction ofit, which he made known in the Transactions of theAcademy of Sciences , at Paris , for that year. It isvery singular that, on this occasion, Du Fay says no-thing of Marriotte, or of the engine in the King’s Library.Leupold, however, had some time before, that is in1724, given a description and figure in his TheatrumMachinarum Hydraulicarum, with which, undoubtedly,Du Fay was not acquainted.

Another improvement, no less useful, is the leathernhose added to the engine, which can be lengthened orshortened as necessary, and to which the fire pipe isapplied, so that the person who directs the jet of watercan approach the fire with less danger. T.his invention,it is well known, belongs to two Dutchmen, both namedJan Van der Heide, who were inspectors of the appa-ratus for extinguishing fires at Amsterdam . The firstpublic experiments made with it took place in 1672,and were attended with so much success, that, at a firenext year, the old engines were used for the last time,the new ones being introduced in their stead. In 1677,the inventor obtafned an exclusive privilege to makethese engines durinn- the period of twenty-five years.

I ti 1682, engines on this construction were distributedin sufficient number throughout the whole city, and theold ones were entirely laid aside. In 1695, there werein Amsterdam sixty of these engines, the nearest six ofwhich were to be employed at every fire; and in thecourse of a few years they were common throughout allth V7- the Netherlands .

All these circumstances have been related by the in-ventor in a particular Work, which, on account of the

excellent engravings it contains, is exceedingly valuable. MachineryOf these, the first seven represented dangerous eonfla- '■“■v—grations at which the old engines were used, but pro-duced very little effect. One of them is the fire whichtook place in the Stadthouse of Amsterdam in the year1652. The twelve following plates represent fireswhich were extinguished by means of the new engines,and exhibit, at the same time, the various ways in whichthe engines may be employed with advantage. Accord-ing to an annexed calculation, the city of Amsterdam lost by ten fires, when the old apparatus was in use,

1,024,130 florins; but in the following five years, afterthe introduction of the new engines, the loss occasionedby forty fires amounted only to 18,355 florins.; so thatthe yearly saving was ninety-eight per cent. Of theinternal construction of these engines no description orplates have been given, nor is there any reason tobelieve they were furnished with an air chamber, thoughin the patents they were always called spouting-engineswhich threw up one continued jet of water. Theaccount given even of the nature of the pipe or hose isshort and defective, probably with a view to render itmore difficult to be imitated. It is only said that it wasmade of leather in a particular manner, and that besidesbeing thick, it was capable of resisting the force of thewater. The conducting or feeding hose was also theinvention of the same two Dutchmen, the end intendedto be placed in the pond or river having been by theminserted in a cork to float it, and its end was defendedby a grating or brass plate pierced with small holes toprevent any mud or dirt from entering.

Here then, with the exception of the air vessel, is thecompletion of the invention of the fire engine, viz. asucking and forcing pump, some method to preserve aconstant stream of water, flexible hose for bringingwater from any approachable supply, and a directingpipe furnished also with flexible hose for conducting thejet of water into narrow places into which the engineitself could not be taken. The modern fire engine inprinciple is no more than this with the addition of anair vessel, but the progress of the Arts has of courseadded much to the perfection and performance of it inother respects as compared with those of the old con-struction, and the forms it has undergone have beenproportionally numerous. Notwithstanding hose wereundoubtedly known on the Continent many years beforethey were used in England, they were always more orless defective; some were made of canvass covered witha cement to make them water tight, some were wovenin the tubular form by looms or Machines made ex-pressly for the purpose, and others were made of leather,which is the material now commonly employed in thisCountry ; and as preserving them always water tight isa matter of some difficulty, several ingenious personshave directed their attention to this object.

One of the most recent improvements in their con-struction is due to Mr. Perkins, so well known for hismany ingenious inventions. The usual method of closingthe two edges of the leather to form the hose, was bysewing them together as a shoemaker closes the leather ofa pair of boots, but Mr. Perkins recommends that insteadof sewing them, the sides should be closed with rivets,indeed the rivet had been before employed for this purposeby Messrs. Hancock and Sellers of Philadelphia , for seve-ral years; butMr.Perkins s operates somewhat differently.

He recommends that the leather should be more over-lapped, and has invented a method of connecting two