always kept to the same level, need not be above six inches; but, as it is seldom practicable to keep the head to the same level, it is better to have the bottom of the pond or cistern sufficiently high to effect the desired object; in which case, so long as there is any water in the cistern at all, the jet will rise to the proper height.

Where a natural head of water of the proper height cannot be obtained, recourse may be had to artificial means of raising water to an elevated cistern or reservoir. This cistern may either be placed on a natural or artificial eminence, or on the summit of a building. In pleasure-grounds, an artificial mount, or piece of conical rockwork, would afford a good situation; and a simple tower, round or square, is also at once a cheap mode of elevating a cistern, and of adding to grounds an ornament, which, if not very beautiful, can yet never be considered mean or paltry.

The water may be raised to the basin or cistern so placed, by forcing-pumps worked by men, horses, wind, water, or steam; or by that very ingenious machine, the hydraulic ram, which we have before noticed (Vol. V. p. 594.) as being in use at Bury Hill; and which has lately been put up, in various parts of the country, for this purpose, by Mr. Rowley. However, the mode which we would recommend, as most directly applicable where there is no natural power, is that of having a small steam-engine, say of two-horse power, which might be placed in the lower part of the tower containing the cistern, or in any convenient situation near the well, pond, or other

source of supply, and set to work once or twice a week, as occasion might require. A horizontal windmill, so disguised in the tower as not to be an offensive object, would, in all elevated situations, as we have elsewhere observed (Encyc. of Cottage Architecture, § 1256.), be the cheapest and best that could be employed; because it would require little or no attention, and might be left to itself, to work or stand still, according to the wind. The construction of such a windmill is exceedingly simple, and no man that we know is more fit to carry the design into execution than Mr. Thorold of Norwich. In some situations, where there is no other employment for the poor, it might be an act of charity to set them to work on a machine for raising water for this and other purposes, though we would not be understood to recommend, as a general principle, such a misapplication of human labour. Whatever can be done by a machine ought never to be attempted by

man.

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 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, &c.; or (and which is one of the newest forms) the convolvulus of Mr. Rowley, as shown in fig. 62. 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 will there 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 an inch; but, for jets like those in the preceding figures, the diameter ought to be two inches ; and, for the number of jets shown in fig. 66. (which is an old rustic Dutch form, of easy execution in flints and cement, the basin being of earthenware), two inches and a half, or three inches, will be found requisite. 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 600 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, or in the same fountain, 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 ought to

be semiglobular 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 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, in order to let the air out. 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.

The perpendicular height to which water will rise in a jet has a limit, depending on the diameter of the jet, and on the

specific gravity of the water and on that of the air which it has to penetrate. A jet of salt water will rise higher than one of fresh water; a column six inches in diameter higher than one of three inches; and a jet of water of any dimension higher at Madrid or Munich than in Paris or London, on account of the difference of the elevation of these cities above the level of the sea. The most powerful garden jet in Europe is that in the Nymphenburg gardens, near Munich. The water is there forced by the direct influence of machinery, without the intervention of a head or reservoir; and it is found that a column of six inches in diameter cannot, even there, be raised higher than ninety feet. A similar column, at St. Cloud (fig. 67.), is said not to rise higher than sixty or seventy feet. It must be recollected that water boils at Munich at 209°; whereas at St. Cloud it requires 212° to effect ebullition.

Thinking it most desirable to attempt to revive the taste for fountains in garden scenery (not, indeed, the childish baubles of the middle ages, when the object was to surprise or frighten the spectator, or probably to wet his clothes, but those classical forms which characterise the modern fountains of Italy, and especially those of Rome), we here present two designs: