Fig. 169.
Bellows-pump (Page 186). This is an atmospheric pump in which the part of the piston is played by the top leaf of the bellows. A very simple method of describing an invention, from which great good in drainage of waste lands in Europe, was realized. “There was of course a valve covering the interior orifice of the nozzle and opening outwards, to prevent the air from entering when the upper board was raised. This valve is not shown because the art of representing the interior of machines by section, was not then understood, or not practiced. The lower board is fastened to the ground by a platform while the suction pipe dips into the water. A weight is placed on the upper board to assist in expelling the water.”
Fig. 169 represents a Double Lantern Bellows-Pump as used in the 16th century. This engraving is plain and requires no description. Fig. 170 shows a diaphragm pump in which a sheet of rubber or its equivalent is used as a substitute for a piston in a cylinder.
Fig. 170.
Note.—When an ox or a horse plunges his mouth into a stream, he dilates his chest and the atmosphere forces the liquid up into his stomach precisely as up the pipe of a pump. It is indeed in imitation of these natural pumps that water is raised in artificial ones. The thorax is the pump; the muscular energy of the animal, the power that works it; the throat is the pipe, the lower orifice of which is the mouth, and which he must necessarily insert into the liquid he thus pumps into his stomach. The capacious chest of the tall camel, or of the still taller cameleopard or giraffe, whose head sometimes moves twenty feet from the ground, is a large bellows-pump which raises water through the long channel or pipe in his neck. The elephant by a similar pneumatic apparatus, elevates the liquid through that flexible “suction pipe,” his proboscis; and those nimble engineers, the common house-flies, raise it through their minikin trunks in the manner of the gigantic animals which in remote ages roamed over this planet, and which quenched their thirst as the ox does. There could have been none which stood so high as to have their stomachs thirty feet above the water they thus raised into them.
Rope Pump. This machine consists of one or more endless ropes, all stretched on two pulleys as shown in Figs. 171 and 172. These pulleys have grooves formed in their surfaces for the reception of the ropes. A rapid rotary motion is communicated to the upper pulley, by a multiplying wheel, and the ascending side of each rope carries up the water absorbed by it, and which is separated from it while passing over the upper pulley, partly by centrifugal force, and partly by being squeezed in the deep groove.
