Fig. 1066. Double lantern-bellows pump. As one bellows is distended by lever, air is rarefied within it, and water passes up suction-pipe to fill space; at same time other bellows is compressed, and expels its contents through discharge-pipe; valves working the same as in the ordinary force-pump.

Fig. 1067. Old rotary pump. Lower aperture entrance for water, and upper for exit. Central part revolves with its valves, which fit accurately to inner surface of outer cylinder. The projection shown in lower side of cylinder is an abutment to close the valves when they reach that point.

Fig. 1068. Cary's rotary pump. Within the fixed cylinder there is placed a revolving drum B, attached to an axle A. Heart-shaped cam A, surrounding axle, is also fixed. Revolution of drum causes sliding pistons c, c, to move in and out, in obedience to form of cam. Water enters and is removed from the chamber through ports L and M; the directions are indicated by arrows. Cam is so placed that each piston is, in succession, forced back to its seat when opposite E, and at same time other piston is forced fully against inner side of chamber, thus driving before it water already there into exit-pipe H, and drawing after it, through suction-pipe F, the stream of supply.

Fig. 1069. Hiero's fountain. Water being poured into upper vessel descends tube on right into lower; intermediate vessel being also filled and more water poured into upper, confined air in cavities over water in lower and intermediate vessels, and in communication tube on left, being compressed, drives by its elastic force a jet up central tube.

Fig. 1070. Diaphragm forcing pump. A flexible diaphragm is employed instead of bellows, and valves are arranged same as in preceding.

Fig. 1071. Common mode of raising water from wells of inconsiderable depth. Counterbalance equals about 1/2 weight to be raised, so that the bucket has to be pulled down when empty, and is assisted in elevating it when full by counterbalance.

Fig. 1072. The common pulley and buckets for raising water; the empty bucketis pulled down to raise the full one.

Fig. 1073. Reciprocating lift for wells. Top part represents horizontal wind-wheel on a shaft which carries spiral thread. Coupling of latter allows small vibration, that it may act on one worm-wheel at a time. Behind worm-wheels are pulleys, over which passes rope which carries bucket at each extremity. In centre is vibrating tappet, against which bucket strikes in its ascent, and which, by means of arm in step wherein spiral and shaft are supported, traverses spiral from one wheel to other, so that the bucket which has delivered water is lowered and other one raised.

Fig. 1074. Fairbairn's bailing scoop, for elevating water short distances. The scoop is connected by pitman to end of a lever or of a beam of single-acting engine. Distance of lift may be altered by placing end of rod in notches shown in figure.

Fig. 1075. Another apparatus operating on the same principle as Fig. 1086. It is termed a Lansdell's steam siphon pump. A is the jet-pipe; B, B, are 2 suction-pipes, having a forked connection with the discharge-pipe C. The steam jet-pipe entering at the fork offers no obstacle to the upward passage of the water, which moves upward in an unbroken current.

Fig. 1076. Pendulums or swinging gutters for raking water by their pendulous motions. Terminations at bottom are scoops, and at top open pipes; intermediate angles are formed with boxes and flap-valve, each connected with 2 branches of pipe.

Fig. 1077. Chain pumps; lifting water by continuous circular motion. Wood or metal discs, carried by endless chain, are adapted to water-tight cylinder, and form with it a succession of buckets filled with water. Power is applied at upper wheel.

Fig. 1078. Self-acting weir and scouring sluice. Two leaves turn on pivots below centres; upper leaf much larger than lower, and turns in direction of stream, while lower turns against it. Top edge of lower leaf overlaps bottom edge of upper one, and is forced against it by pressure of water. In ordinary states of stream, counteracting pressures keep weir vertical and closed, as in the left-hand figure, and water flows through notch in upper leaf but on water rising above ordinary level, pressure above ' from greater surface and leverage overcomes resistance below, upper leaf turns over, pushing back lower, reducing obstructions, and opening at bed a passage to deposit.

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Fig. 1079. Balance pumps. Pair worked reciprocally by a person pressing alternately on opposite ends of lever or beam.

Fig. 1080. Steam hammer. Cylinder fixed above and hammer attached to lower end of piston-rod. Steam being alternately admitted below piston and allowed to escape, raises and lets fall the hammer.

Fig. 1081. Hotchkiss's atmospheric hammer; derives the force of its blow from compressed air. Hammer-head C is attached to a piston fitted to a cylinder B, which is connected by a rod D with a crank A on the rotary driving shaft. As the cylinder ascends, air entering hole e is compressed below piston and lifts hammer. As cylinder descends, air entering hole e is compressed above, and is stored up to produce the blow by its instant expansion after the crank and connecting rod turn bottom centre.

Fig. 1082. French invention for obtaining rotary motion from different temperatures in 2 bodies of water. Two cisterns contain water; that in left at natural temperature, and that in right higher. In right is a water-wheel geared with Archimedean screw in left. From spiral screw of the latter a pipe extends over and passes to the under side of wheel. Machine is started by turning screw in opposite direction to that for raising water, thus forcing down air, which ascends in tube, crosses and descends, and imparts motion to wheel; and its volume increasing with change of temperature, it is said, keeps the machine in motion. We are not informed how the difference of temperature is to be maintained.