In conducting the water from the cistern or reservoir to the jet or fountain, the following particulars require to be attended to: In the first place, all the pipes must be laid sufficiently deep in the earth, or otherwise placed and protected so as to prevent the possibility of their being reached by frost; next, as a general rule, the diameter of the orifice from which the jet of water proceeds, technically called the bore of the quill, ought to be four times less than the bore of the conduit pipe; that is, the quill and the pipe ought to be in a quadruple proportion to each other. There are several sorts of quills or spouts, which throw the water up or down, into a variety of forms: such as fans, parasols, sheaves, showers, mushrooms, inverted bells, etc. The larger the conduit pipes are, the more freely will the jets display their different forms; and the fewer the holes in the quill or jet (for sometimes this is pierced like the rose of a watering pot) the greater certainty there will be of the form continuing the same; because the risk of any of the holes choking up will be less. The diameter of a conduit pipe ought in no case to be less than one inch; but for jets of very large size, the diameter ought to be two inches. Where the conduit pipes are of great length, say upwards of 1000 feet, it is found advantageous to begin, at the reservoir or cistern, with pipes of a diameter somewhat greater than those which deliver the water to the quills, because the water, in a pipe of uniform diameter of so great a length, is found to lose much of its strength, and become what is technically called sleepy: while the different sizes quicken it, and redouble its force. For example, in a conduit pipe of 1800 feet in length, the first six hundred feet may be laid with pipes of eight inches in diameter, the next 600 feet with pipes of six inches in diameter, and the last 600 feet with pipes of four inches in diameter. In conduits not exceeding 900 feet, the same diameter may be continued throughout. When several jets are to play in several fountains, or in the same, it is not necessary to lay a fresh pipe from each jet to the reservoir; a main of sufficient size, with branch pipes to each jet, being all that is required. Where the conduit pipe enters the reservoir or cistern, it ought to be of increased diameter, and the grating placed over it to keep out leaves and other matters which might choke it up, ought to be semi-globular or conical; so that the area of the number of holes in it may exceed the area of the orifice of the conduit pipe. The object is to prevent any diminution of pressure from the body of water in the cistern, and to facilitate the flow of the water. Where the conduit pipe joins the fountain, there, of course, ought to be a cock for turning the water off and on; and particular care must be taken that as much water may pass through the oval hole of this cock as passes through the circular hole of the pipe. In conduit pipes, all elbows, bendings, and right angles should be avoided as much as possible, since they diminish the force of the water. In very long conduit pipes, air-holes formed by soldering on upright pieces of pipe, terminating in inverted valves or suckers, should be made at convenient distances, and protected by shafts built of stone or brick, and covered with movable gratings, in order to let out the air. Where pipes ascend and descend on very irregular surfaces, the strain on the lowest parts of the pipe is always the greatest; unless care is taken to relieve this by the judicious disposition of cocks and air-holes. Without this precaution, pipes conducted over irregular surfaces will not last nearly so long as those conducted over a level.- Encycl. of Cottage, Farm, and Villa Architecture, page 989.
