Chap. XVII.

THEORY OF THE MOTION OF FLUIDS.

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l\ V O O oj;

Fig. 1761.

PLAN OF SIPHON AND SUCTION RAM.

Fig. 1762. KHBB is the branch of a siphon which leads the water from the source; itflows through the apertures N, N, N, falls into the cistern P Q S R, and joins the lower waters,

Fig. 1762. SECTION OP SIPHON and SUCTION RAM.

X Y; H is a funnel, garnished with a stop-cock to feed the siphon ; T is the suction tube,which arises from above the ascension valves M, M, M ; below these same valves is a wooden

float, which is lowered by the action of the air-bed, and which rises by the action of thewater in the body of the ram against the ascension valves : the space in which the floatermoves is called the lift of the floater. O is the small canal through which the outerair enters the reservoir L; a b is the ascension tube.

Fig. 1763. shows on a larger scale, 1st, the ascension valve ; 2d, the air valve Is O, whichserves to maintain the air in the reservoir L; 3d, the floater’s lift, Z. In the ram executedat Marly there is no suction tube, but the siphon form is preserved, as in the firstproject; the inconveniences which result from this form for rams of a large size weredifficult to foresee : in small rams it is necessary to introduce the external air into the space