P U M P. 



IIH nt on 

 the hoe 

 of lire 

 rnginet. 



l'i \ i i- 



rump, when two hose were connected together the one over- 

 lapped tin 1 other, and the waterway being thus xuddni- 

 Iv contracted at the joints, its velocity was retarded. 

 Messrs. Hancock and Sellers of Philadelphia seem to 

 have been the first who joined hose together by rivett- 

 ing in place of sewing, and this method has been suc- 

 .lly practised for more than twelve years. Mr. 

 Perkins, however, has made come essential improve- 

 \ ! V XXI ents oil this method. He recommends that the Irath- 

 Pigf. 5, 6. ers 8noi ild be more overlapped, nd has invented a me- 

 thod of connecting two hose without contracting the 

 waterway at the joints. These improvements are shown 

 in Fig. 5, 6'. The rivets represented in Fig. 5. are 

 made of copper, which not only lasts four or five times 

 longer than the best thread, but if the overlap is suffi- 

 cient, the pressure of the water against the overlap acts 

 as a valve to tighten the seam. As the portion of the 

 hose next the engine has been found to burst most fre- 

 quently, especially when the water is carried perpendi- 

 cularly, the first, third, or fourth portions are doubly 

 rivetted, as in Fig. 5, the rest having only a single 

 row of rivets. When a rivet breaks, it is replaced by 

 making an opening in the seam of a sufficient size to 

 allow the hand to replace, not merely the rivet thac is 

 broken, but those taken out to form the opening. When 

 the rivets are pressed in the holes, they are swelled by 

 placing them upon a flat bar of iron introduced into the 

 entrance of the hose. The rivet and burr should both 

 be of wrought copper, and not of different materials. 

 Tin rivets, for example, with copper burrs will, in con- 

 sequence of the galvanic action, destroy the leather in 

 a few months. The method of connecting the hose is 

 shown, in Fig. 6, where A is the female part of the 

 swivel joint attached to the hose by the female screw 

 re, and prevented from collapsing by the hoop ring d 

 within it. On the outer side of this screw is a groove 

 bb, on which the swivel ring aa revolves ; this ring 

 being fixed to the female connecting screw B, by means 

 of rivetting on the end of it &tf. The male screw C 

 is attached to another portion of hose in the manner 

 already described. The different pieces of leather that 

 compose the hose are connected by a spiral joining of 

 double rivets. See the Transactions of the Society of 

 Arts, vol. xxxviii. p. 102. 



For farther information on the subject of fire-en- 

 gines, see Phil. Trans. 1670', vol. xi. p. C79- Reau- 

 mur's engine, Mem. Acad. Par. 1722 ; Machines Ap- 

 promees, torn. i. p. 151. Ublemann's engine, Mem. 

 Acad. 1722, and Mach. Approuv. torn. iv. 35. Gen- 

 sanne's engine, Mach. Approuv torn. vii. 95. Thillay's 

 engine, Mem. Acad. 174-6, Hist. 120. Bonnet's engine, 

 Mem. Acad. 17^9, Hist- 182. Dearborn's engine, Mem. 

 Amer. Acad. <f Arts, 1794-, vol. i. p. 520. Bramah's 

 engine, Repertory of Arts, vol. iii. p. 363. Simpkin's 

 engine. Repertory of Arls, vol. vii. p. 301. See also 

 Belidor's Architect, llydiuitl. vol. ii. p. 186'. Emerson's 

 Mechanics, p. 275. An account of the history of fire- 

 engines, by Beckmann, will be found in the 1'htl. Mag. 

 vol. xi. p. 238, or in his Hist, of Inventions, vol. iv. p. 75. 



21. Description of various Pumps, by Ramelli and others. 



Rescrip- As these different pumps all resemble one another 



tionofva- in principle, we shall describe them under the same 



nous section. They are represented in Plate CCCCLXXI. 



pumps by figs. 7, 8, 9, and 10. 



In Fig. 7, AB is a lever moving round C as a cen- 

 and others. . n ,P r,nn 



Fin 26 ' * ne en " "^ works in a box CBr, immersed in 



the water WW. When AC is pulled to the left, the 



end BC forces out the water up the pipe E and throu '' 



tin- valve v into the pipe Ev, where it in kept by t.'ie * *v ' * 

 dr-.cent of the valve v. The water enters the box by 

 an aperture below 1!. 



In Fig. 8 a wheel A, with three spiral wing*, B, I'LATI: 

 C, D, revolves round A in the centre, and is immersed cti 

 in the water WW. When C ascend* towards F, the * * ' 

 water between C and F is forced up into the pipe HG, i *' K 

 ;uid is detained by the descent of the valve r, the rod 

 l-'IO rising between the guides or rollers mn as c advan- 

 ces to F, for the purpose of preventing the water from 

 getting through at F. The next wing D produces the 

 same effect, carrying up the water above its natural 

 level WW to the pipe II. 



In Fig. 9, which is taken from the cabinet of Ser- !''* 9 - 

 vier, there are two revolving wheels AB, which work 

 in one another, and are pulled close to the elliptical 

 cistern DC. The water which rises through the pipe 

 E into C is forced by these wheels round the outer teeth 

 up to D, and consequently up the pipe F. Ramelli 

 had previously given a pump of this kind, in which 

 there was only one wheel, with a rod like EF in Fig. 

 27. See Nicholson's Journal, vol. viii. p. 35. 



In Fig. 10 the very same effect is produced by a Fig. I- 

 wheel A, furnished with a number of vanes, m, n, d, 

 which fall down on the circumference of the wheel at 

 the side, and resume their other position by the action 

 of a spring s attached to each of them. They will con- 

 sequently force up the water from D to C. 



22. Description of Brown's Atmospheric Engine, in 

 tv/dch a vacuum is ejj'ccled iy burning oil or coal gat 

 toilhin the cylinder. 



We have seen a model of a pump in which the air 

 in the barrel was rarefied by burning the shavings of 

 wood at the top of the barrel, an airtight cap be- 

 ing put on when the rarefaction was supposed to be at 

 a maximum. A certain quantity of water was thus 

 raised above the valve at the bottom of the barrel, and 

 the operation was repeated till the water rose to the 

 desired height. Though this expedient might be 

 found useful in cases of exigency, it had not a suffi- 

 ciently practical character, and we have not heard of 

 its being introduced. 



An analogous though totally different principle has 

 been happily applied by Mr. Samuel Brown to cre- 

 ate a vacuum in pumping engines, which may be 

 employed both to raise water and drive machinery. 

 The specification of the patent by which Mr. Brown 

 has secured his right to this invention, was enrolled 

 only in June 1824, so that we are not able to speak >f 

 this invention on the authority of any actual trial of it 

 on a large scale. The principle, however, cf the in- 

 vention is Highly ingenious, and we are disposed to 

 view it as a formidable rival to the steam engine in its 

 best form. 



In its general character of an atmospherial engine, 

 Mr. Brown's invention resembles the steam engines of 

 Savery and Newcomen, but the vacuum is effected 

 by burning coal or oil as within the cylinder, so as to 

 consume the atmospheric air. 



The general appearance of Mr. Brown's engine rs 

 represented in Plate CCCCLXXI. No. I. Fig. 11, where 

 a and b are the two cylinders in which the vacuum is to 

 be produced, rand d two rising mains leading from the 

 reservoir to the top of the cylinders a, b. Coal or oil 

 gas is conveyed from a gasometer through the pipes c 

 andyi the last of which passes into the cylinders, and 



Descrip- 

 tion of 

 Brown's 

 atmosphe- 

 ric engine, 

 in which * 

 vacuum i* 

 effected by 

 burning 

 gas in the 

 cylinder. 



Pig. 11. 



