ENGINE. 



packed with hemp round the collar, 

 makes a tight joint ; the piston, D, is 

 affixed to the spindle within the cylinder, 

 and fits it tight all round by means of 

 leathers, applied as described in the beer- 

 engine ; at E, fig. 4, a partition, called a 

 saddle, is fixed in the cylinder, and fits 

 against the back of the spindle tight by a 

 leather. 



We have now a cylinder divided by 

 the saddle, E, and piston, into two parts, 

 whose capacity can be increased and di- 

 minished by movir.g the piston, with pro- 

 per passages and valves to bring and con- 

 vey away the water: this will form a 

 pump. These passages are cast in one 

 piece with the cylinder : one, d, for bring- 

 ing the water, is square, and extends 

 about | round the cylinder; it connects 

 at bottom with a pipe, e ; at its two upper 

 ends opens into two large chambers,/^, 

 extending near the whole length of the 

 cylinder, and closed by covers, h A, 

 screwed on : i k, are square openings 

 (shown by clotted squares in fig. 3. ) in the 

 cylinder, communicating with the cham- 

 bers : / ff, I m, .are two valves, closing 

 their ends of the curved passage, c7, and 

 preventing any water returning down the 

 passage, d: n o, are two passages from 

 the top of the cylinder, to convey away 

 the water ; they come out in the top ofthe 

 cylinder, which, together with the top of 

 the chambers,/,^, form a large, flat sur- 

 face, and are covered by two valves, p y t 

 to retain the water which has passed 

 through them. A chamber, K, is screw- 

 ed over these valves : and has the air 

 vessel k, fig. 1 and 2, screwed into its 

 top ; from each side of this chamber a 

 pipe, iv iv, proceeds, to which a hose is 

 screwed, as shown in fig. 1. Levers, x x, 

 are fixed to the spindle at each end, as 

 shown in fig. 1, and carry the handles, 

 H H, by which men work the engine. 

 U hen the piston moves, as shown by the 

 arrow in fig. 4, it produces a vacuum in 

 chamber,/, and that part ofthe cylinder 

 contiguous to it ; the water in the pipe, 

 e, then opens the valve, m, and fills the 

 cylinder. The same motion forces the 

 water contained in the other part of the 

 cylinder through the valve, q, into cham- 

 ber, K, and thence to the hose through 

 the pipe, w; the piston being turned the 

 other way reverses the operation, with 

 respect to the valves, though it continues 

 the same in itself. The pipe, e, is screw- 

 ed by a flanch to an upright pipe, P, 

 fig. 5, connected with another squareiron 

 pipe, fastened along the bottom of the 

 chest of the engine : a curved brass tube, 



G, comes from this pipe, through the end 

 ofthe chest, and is cut into a screw, to 

 fit on the suction hose, when it can be 

 used ; at.other times a close cap is screw- 

 ed on, and another brass cap at H, within 

 the chest, is screwed upwards on its 

 socket, to open several small holes made 

 in it, and allow the water to enter into the 

 pipe ; in this case the engine chest must 

 be kept full of water by buckets. The 

 valves are made of brass, and turn upon 

 hinges. The principal advantage of the 

 engine is the facility with which it is 

 cleaned from any sand, gravel, or other 

 obstructions, which a fire-engine will al- 

 ways gather when at work. 



The chambers, /,_-, being so large, al- 

 low sufficient room to lodge a greater 

 quantity of dirt than is likely to be accu- 

 mulated in the use of the engine at any 

 one fire ; and if any of it accidently falls 

 into the cylinder, it is gently lifted out 

 again into the chambers by the piston, 

 without being any obstruction to its mo- 

 tion : to clear the engine from the dirt, 

 two circular plates, r r, five inches diame- 

 ter, are unscrewed from the lids, h h, of 

 the chambers/ g, and when cleaned are 

 screwed on again : these screw covers fit 

 perfectly tight without leather, and can 

 be taken out, the engine cleared, and 

 enclosed again in a very short time, even 

 when the engine is in use, if found ne- 

 cessary. 



The two upper valves, p q, and cham- 

 ber, K, can also be cleared with equal 

 ease, by screwing out the air vessel, k k, 

 fig. 1, which opens an aperture of five 

 inches, and fits air-tight, without leather, 

 when closed. The valves may be repair- 

 ed through the same openings. ' The use 

 of the air-vessel k k, fig. 1 and 2, is to 

 equalize the jet from the engine during 

 the short intennittance of motion at the 

 return of the piston stroke : this it does 

 by the elasticity of the compressed air 

 within it, which forces the water out con- 

 tinually, though not supplied quite regu- 

 larly from the engine. 



The engine from which our drawing 

 was taken was made for the Sun Fire 

 Insurance Company, in London, and from 

 some experiments made by their agent, 

 Mr. Samuel Hubert, appears to answer 

 e very purpose. 



EJTGIXE, for raising -water. The frame 

 ofthe machine is of cast iron, nearly in 

 the form of the letter A; there are two 

 of these frames, B B, (fig. 1, Plate Pump- 

 Engine,) screwed together by means of 

 five wrought iron pillars, a a a 'a ; D is 

 another smallerframe, to support the axis 



