WATER RAM

An ingenious hydraulic machine for raising water by means of its impulse. The principle of its action and the mechanism its construction may be described as follows: irWr^i - gVivj The water arriving at A from the reservoir with the locity due to the height of the fall, pa es along the pipe B, which should have an Inclination of at least an inch every two yards, escapes through an orifice C, which may be shut at pleasure by means of a valve. A reservoir, filled with air, is attached by means of a cylinder, a b c d, the pipe ADD; in the middle of the bottom of the reservoirFis a circular orifice, to which there is adapted a short cylindrical tube, of which the extremity E is also furnished with a valve. Another valve, S, serves to supply the air the space comprised between the cylinder abed and tube E. G I H is an ascensional tube rising from the reservoir F. The water which escapes at C is carried off by waste pipe K L. The form of this apparatus (or perhaps its mode of tion) suggested the name it has received. The pipe ABC is called the body of the ram; and the extremity, where valves and the reservoir F are placed, is called its head. Both valves D and E are formed of hollow balls supported on muzzles, and of such a thickne of metal that they weigh about twice as much as the quantity of water they displace. We may now consider the effects of the engine when action. The water, flowing through the orifice C, acquires the velocity duo to the height of the fall, and raises the D from its support till it comes to the orifice C; the extremity of this orifice is covered with leather, or with cloth filled with pitch, so that when the ball is applied to it, the pa age of the water is effectually prevented. As soon as this fice is closed, the water raises the ball E which had shut the orifice of the reservoir F, and a portion of it introduces itself into this reservoir, and into the pipe G I H. It thus loses the velocity which it had when the orifice C was shut, and the balls D and E fall down in consequence, the one on its support, and the other on the orifice at E. VVhen this takes place, everything is in the same state in which it was at first. The water begins again to flow through the orifice C; the valve D is again shut; and the same effects are pea ted in an interval of time, which, for the same ram, der goes little variation. Every time the impulse is renewed, a quantity of water forced up into the reservoir F and the tube H; and as it prevented from returning by the action of the valve, it must nece arily be delivered at the extremity of H. The use the air-ve el F is to keep up a continuous motion of the ascending column of water. The communication with external atmosphere being cut off, the air within F is compre ed by a force proportional to the height of the surface of the water in H above its surface in F; and this compre ed air,acting by its elasticity on the water, maintains continuous flow through H. The air-ve el, however, though it a ists the action of the ram, is not an e ential part of it; the continuity of the discharge of water may effected by means of two or more rams, of which the ascensional pipes GUI all terminate in a single branch. On this principle works have been erected at Marly, in France, which raise water in a continuous jet to the height of metres, or 187 English feet. As Ihe ascending column of water communicates with the air in the reservoir F, this would soon be exhausted if fresh jiortion of air were not introduced at each stroke of the ram. The little tube S, which is stopped by a valve opening inwards, serves for this purpose. At the instant when the orifice C is closed a recoil takes place, by which the water is thrown back from the head of the ram towards the 574 [s. 588]