Chap. XVII.

MACHINES FOR RAISING WATER.

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forcing and suction-pumps, and the valves operated precisely in the same manner. D is avalve at the bottom of each cistern to empty it, which was effected by simply turning thehandle at the end of the rod : when the machine was in fullwork it threw up 168264 cube feet in 24 hours, and employed l

60 workmen to keep it in condition. M •

Fig. 1877. is a machine invented by Belidor for raisingwater by means of a fall. The water from the source is dis-charged into the cistern C, at whose lower part is a pipe Cl),

10 or 11 feet high, kept continually full. The water on issuingfrom the pipe C D is divided into two unequal parts, of whichthe lesser passes along the pipe G II, anti up G L, into thecistern M, and then down the pipe M N to the cistern of dis-tribution ; the space FE comprises the machine represented indetail at fig. 1878. A15 C 1), EFGII. are two pump-barrelsunited by a pipe, I K E G, open at LMNO to facilitate themotion of the pin which passes through the piston rods It andS, whose stroke is limited by ML and NO. I is the pipemarked C 1) in the preceding figure, having two branches atright angles to each other : the first, I Y, joins the communi-cation pipe Y V, which conducts water into the small pump-barrel, and the second, TZ, is united to a cock, which admits itto the large one. This cock has three conical branches; thefirst is united to the pump-barrel, the second introduces thewater which gives impulse to the piston, the third facilitatesthe escape of the same water : the tap of this cask acts at twoseparate times, making a quarter of a revolution at each, tothe right and left, communicating alternately with the pump-barrel and the discharge pipe, so that the water escapes fromthe former while the supply pipe is closed by the solid part ofthe tap P.

Fig. 1879. represents this cock in detail : A is a plan of thethree conical branches; 15 is a section through the two oppositebranches; C a section at right angles to the preceding, and 1) isthe elevation behind ; E is the plan of a jacket between the cockand the branches to prevent leakage ; G is a section, and II anelevation of it, showing that its bottom is slightly convex, and Fig. 1377.that the tap may not touch it, but turn on a pivot in its centre;

F is a plan of the tap, I a section, and K an elevation of it; L is an elevation of the wholeput together, and M a plan and section of its head.

Fig. 1878. BELIDOB’S MACHINE.

Fig. 1880. shows the pistons of this machine, 15 being an elevation, and M a section:both rods consist of hollow cylinders, the less sliding in the greater, as to shorten the entirelength for the purpose of introducing them into the pump-barrels ; at each end is a screw ;A and C, to which the pistons are attached: the pistons themselves, D E F, I K L, consistof a cylinder on which several leather rings are placed, and a washer and nut to tightenthem : to diminish their friction, each is provided with a roller G and II.

The play of this machine will be understood by a reference to fig. 1877. The water inthe pipe C 1) having free communication by HG will rise as high as K : the valves shownin fig. 1878. being pressed upwards, open to allow the water to pass; in doing this it willalso enter the small pump-barrel, and drive the piston R towards 15 I), and consequently Stowards the cock, supposed as at fig. 187 7., where the pipe of admission closes and the dis-charge pipe opens, the air or water in the great pump-barrel can escape : when the piston Sarrives at F II, the cock making suddenly a quarter of a revolution, and opening the sup-ply pipe and closing the escape pipe, the water from the source will drive the pistonforward : for if we suppose its circle six times that of the lesser, there will be six columnsof water equal to K F, acting together against and driving it towards N, the water in the

A II