Water-Ram.

371

Chap. l.J

Operation is continued, as long as the spring affords a sufficient supply andthe apparatus remains in Order.

The surface of the water in the spring o'r söurce should always be keptat the same elevation, so that its pressure against the valve E may alwaysbe uniform—otherwise the weight of E would have to be altered as thesurface of the spring rose and feil.

This beautiful machine may be adapted to numerous locations in everycountry. When the perpendicular fall from the spring to the valve E isbut a few feet, and the water is required to be raised to a considerableheight through F, then, the length of the ram or pipe B, must be in-creased, and to such an extent that the water in it is not forced back intothe spring when E closes, which will always be the case if B is not ofsufficient length. Mr. Millington, who erected several in England, justlyobserves that a : very insignificant pressing column is capable of raising avery high ascending one, so that a sufficient fall of water may be obtainedin almost every running brook, by damming the upper end to produce thereservoir, and carrying the pipe down the natural channel of the streamuntil a sufficient fall is obtained. In this Way a ram has been made to raiseone hutadred hogsheads of water in twenty-four hours to a' perpendicularheight of one hundred and thirty-four feet, by a fall of only four feet anda half. M. Fischer of Schaffhausen , conslructed a water-ram in the formof a beäutiful antique altar, nearly in the style of that of Esculapius, asrepresented in various engravings. A basin about six inches in depth, andfrom eighteen to twenty inches in diameter, received the water that formedthe motive column. This water flowed through pipes three inches in di-ameter that descended in a spiral form into the base of the altar ; on thevalve opening a third of the water escaped, and the rest was forced up toa castle several hundred feet above the level of the Rhine .

A long tube laid along the edge of a rapid river, as the Niagara abovethe falls, or the Mississippi , might thus be used instead of pumps, waterwheels, steam-engines and horses, to raise the water over the highestbanks and supply inland towns, however elevated their location might be;and there is scarcely a farmer in the land but who might, in the absenceof other sources, furnish his dwelling and barns with water in the sameway, from a brook, creek, rivulet or pond.

If a ram" of large dimensions, and made like No. 168, be used to raisewater to a great elevation, it would be subject to an inconvenience thatwould soon destroy the beneficial effect of the air chamber. When speak-i'ng of the air vessels of fire-engines, in the third book, we observed that ifair be subjected to great pressure in contact with water, it in time be-comes incorporated with or absorbed by the latter. As might be supposed,the same thing occurs in water-rams; as these when used are inces-santly at Work both d'ay and night. To remedy this, Montgolfier ingeni-oüsly adapted a very small valve (opening inwards) to the pipe beneath theair chamber, and whi'ch was open'ed and shut by the ördinary action of themachine. Thus, when the flow of the water through B is suddenly stop-ped by the valve E, a partial vacuum is produced immediately below theair chamber by the recoil of the water, at which instant the small valveOpens and a portion öf air enters and supplies that whibh the water ab-sörbs. Sometimes this snifting valve, as it has been named, is adapted toanother chamber immediately below that which forms the reservoir of air,as at B in No. 169. In small rams a sufficient supply is found to enter atthe valve E.

Although air chambers or vessels are not, strietly speaking, constituentelements of water-rams, they are indispensable to the permanent operatidn