198 HYDRAULICS. 



valves, they are both within the reach of a person's 

 hand, and may be cleared at once, without the 

 disjunction of any part of the pump — and that 

 the pump is rendered capable of being instanta- 

 neously converted into an engine for extinguishing 

 fire. Besides, it occupies very little space in the 

 hold, and thus saves room for stowage. 



But this pump is not confined to nautical uses 

 alone; its adaptation extends to the raising of water 

 in all situations, and with peculiar advantage where 

 it happens to be mixed with sand, or substances 

 which destroy other pumps, as, for instance, in 

 alum-works, in mines, in quarries, in the clearing 

 of foundations; and in its double capacity it will 

 be very convenient in gardens, bleaching-grounds, 

 in stable and farm-yards, and in all manufactories, 

 or other places, where there is a necessity for 

 raising water, and the risk of fire. 



With all these advantages, it is a simple and du- 

 rable pump, and may be made either of metal or 

 wood, at a moderate expence. 



Fig. 9. is a vertical section of the pump, as 

 made of metal, in which A is the suction-piece, 

 B the inner valves, C the outer valve. 



The valves are of the kind called clack-valves. 

 Their hinges are generally made of metal, as being 

 more durable than leather. 



D the working-barrel, E the piston, G the spout. 



The following parts are necessary only when the 

 pump is intended to act as a fire-engine. 



H an air-vessel, which is screwed like a hose- 

 pipe, that it may, at pleasure, the more readily be 

 fixed or unfixed. 



There is a perforated stopple tor the spout, made 

 for receiving such pipes as are common to fire- 

 engines. It is oval and tapered, and being intro- 



