In almost all countries, from the earliest times to the present, levers, heavily weighted on the shorter arm, and with a bucket attached to the longer, have been used for raising water from deep wells. The pictorial records of Ancient Egypt attest the antiquity of this method. The shadoof of modern Egypt is the same, and we have seen it used both in that country and on the remotest mission stations in Southern Africa. The mode of applying it will be seen by a glance at our full-page engraving. The water raised by the shadoof is commonly used for irrigation. We, however, found it very valuable during the Crimean war for raising water for both men and horses. When used among the crops, the water is received sometimes in a reservoir with embankments, guarded by matting, and at others, into troughs which lead direct to the main irrigating channel, from which smaller furrows lead off to every part of the field. These are stopped with lumps of clay or earth, and when the water is required in any direction, the irrigator removes the obstruction by thrusting his toes beneath and lifting it out of the way.
In Egypt, India, and other countries, wheels and machines, more or less elaborate, are used for lifting water. There must be, for this purpose, at least one vertical wheel of sufficient diameter to carry an endless band, on which are fastened a series of buckets, in such a manner that they will retain very nearly their perpendicular position, until they surmount the highest portion of the circumference of the wheel, and will then “tip” and discharge the water into a trough or reservoir. These buckets may be wooden bowls, earthen chatty pots, bags of leather or canvas, joints of bamboo, or anything that is moderately water-tight; but, of course, the less leakage there is the better. The band should run round a similar wheel the axle of which is nearly level with the water, so that the band is kept tight and the buckets forced beneath the surface; but this may be dispensed with if the band and upper wheel are sufficiently rough, or if there be studs or points to catch the full buckets and prevent their slipping. The wheel may be turned either by a crank, by manual labour, or oxen or other animals may be employed. In this latter case there may be another larger wheel or drum upon the same axle, and several turns of rope being taken over it, the ox may be driven away, unwinding it as he goes; or an endless screw, sloping at an angle of 45°, may be cut upon the axle, while a similar one working in it is cut upon a vertical shaft. Or cogged wheels of the same angle (as shown in our figure) may be used; the vertical pillar will then be turned by an ox yoked to a cross-bar and walking round it in a circular path; but it will be necessary that the discharging trough should pass beneath a little bridge in this path, and that the communication with the water to be drawn up should either be by a well within the circle, or by a channel to the river passing under a similar bridge. The stancheons of the frame which supports the vertical bar must stand outside and well clear of the path.
We give, also, an example of a box pump. Four deals or boards, of any length or breadth, are nailed together, but their lower ends for about a foot or more should be left a little wider than the rest of the length; two wheels of nearly equal diameter should be fixed, one with part of its circumference below the water, and the other somewhat higher than it is requisite to raise it; an endless band of canvas or other material must pass round both wheels, and one side of it through the trough. On this band must be fastened by one edge a number of boards or floats of such size as nearly to fill the inner diameter of the trough, without being so tight as to stick in any part of it; a hole should be bored in the centre of each, and a small line run through and knotted, so as to keep the floats always at right angles to the band. There should be a spout near the top of the trough, to lead the water off in any required direction. Fig. 2 on the same illustration shows part of an endless band, with pockets or bags stitched on it; these may be of almost any stout material of tolerably close fibre—No. 1 canvas would answer very well. They would discharge the water over the wheel into a reservoir, and no tube, as in Fig. 1, would be needed.
We give, also, an example of wheels driven by water power over and undershot. It would be superfluous to mark these with distinctive figures. In the first the water is conveyed by a pipe or trough, and allowed to fall upon the wheel into buckets or receptacles formed in its periphery by fixing boards across between the two rims, at such angles as are indicated by the dotted lines, which may be taken to represent the heads of the nails driven into their edges; and thus they will retain water until, by the revolution of the wheel, they have sunk so far as to be below the level of the axle, when they allow the water to escape, and come up light and empty on the other side. Some of these wheels are as much as 30ft. or more in diameter; indeed, the larger they are, the greater is the leverage obtained from a given amount of water; and, the wheel once set in motion, the power thus gained may be applied by connecting gear to any mechanical purpose.
The “undershot” simply has boards or floats fixed across it with their edges coinciding with the lines of the spokes. Indeed, if a paddle steamer were anchored in a tideway, and her wheels disconnected and allowed to revolve with the force of the tide, they would furnish a good example of the undershot wheel; and the paddle of a wrecked steamer would be better than anything a colonist with scant appliances could make for the purpose.
Still, with a few tools and a moderate share of ingenuity very fair makeshift water-wheels may be constructed in situations where they may be found most valuable. We have, when among the Tartars, seen them erect a small wooden hut over a narrow rapid mountain stream, leave a sort of trap in the floor, fix in some rough forked tree trunks and beams, and on them mount a little water-wheel made of hewn planks and bars treenailed together on the double-cross system, like that adopted in building up the wheel a in the illustration on p. 511, which is supposed to be erected for mining pumps, and is fed by a two-plank shoot. The Tartar wheels were invariably undershot, like that at B, and were used for setting in motion the trip hammers used in fulling their coarse native woollen.