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the top of one cylinder. The mill is fed by introducing the cane between the rollers, by which it is crushed and carried over to the other side. The expressed juice runs through a channel below into a large reservoir, whence it is transferred to boilers, and, being there sufficiently inspissated, is sent in tubs to the refiners. In the above instance the mechanism might be evidently economised and improved by causing the cylinder, which communicates motion, to turn two others instead of only one. This is known to be the practice in our West Indian colonies.
The Chinese excel in their contrivances for raising water in the irrigation of their lands, and it is probable that these inventions are nearly as old as their husbandry itself. One of them is an ingenious species of chain-pump, which we give here, as it is well described and figured in Staunton's Embassy.* The pump consists, in the first place, of a hollow trough or trunk, of a square make. Flat and square pieces of wood, corresponding exactly to the dimensions of the cavity of the trunk, are fixed to a (jointed) chain, which turns over a roller or small wheel placed at each extremity of the trunk. The square pieces of wood fixed to the chain move with it round the rollers, and lift up a volume of water equal to the dimensions of the hollow trunk. The power used in working this machine is applicable in three different ways: if the machine be intended to lift a great quantity of water, several sets of wooden arms are made to project from various parts of the lengthened axis of the roller, over which the chain and lifters turn. These arms are shaped like the letter T, and made round and smooth for the foot to rest upon. The axis turns upon two upright pieces of wood, kept steady by a pole stretched across them. The machine being fixed, men treading upon the projecting arms of the axis, and
* Vol. ii. p. 480.
supporting themselves by the beam across the uprights, communicate a rotatory motion to the chain, the lifters attached to which draw up a constant and copious stream
of water.* This manner of working the chain-pump is illustrated in the preceding cut, and is applied principally to raising water to small heights from rivers or canals: frequently to pumping out the holds of their merchant-vessels. .“ Another method of working this machine,” continues Staunton, “is by yoking a buffalo or other animal to a large horizontal wheel, connected by cogs with the axis of
* These lifters go up through the inside of the trough, and come down again above it, in a reversed position.
the rollers over which the lifters or boards turn. This mode was observed by the travellers only at Chusan. A small machine of this kind (in the third place) is worked merely by the hand, with the assistance of a trundle and simple crank, such as are applied to a common grindstone, fixed to one end of the axis of the chain-pump. This last method is general throughout the empire. Every labourer is in possession of such a portable machine—an implement to him not less useful (in rice cultivation) than a spade to an European peasant. The making of those machines gives employment to a great number of artificers.”
But by far the most ingenious and useful contrivance for irrigating lands is that which our embassies met with on the river that flows down, with a rapid stream, from the ridge of mountains bounding the Canton province on the north (and called the Meiling pass), towards the Poyang lake and the Yang-tse-keang. The velocity of the current has worn away the banks, which consist of a loose soil, to the depth in some places of thirty feet and more. Here the chain-pump already described becomes altogether unavailable, as the weight and pressure of a column of water of that height, and the friction of the length of chain required, put it out of the question. But Chinese ingenuity has converted the strength of the stream into a means of overcoming the very difficulties which it originally occasioned ; and one is at a loss which most to admire, the cleverness and efficiency, or the cheapness and simplicity, of the contrivance. The wheel, which is turned by the stream, varies from twenty to thirty feet or more in height, according to the elevation of the bank; and, when once erected, a constant supply of water is poured by it day and night into a trough on the summit of the river's side, and conducted in channels to all parts of the sugar plantations which there chiefly occupy the lands.
The props of the wheel are of timber, and the axis is a cylinder of the same material; but every other portion of
the machine exhibits some modification or other of the bamboo, even to the fastenings and bindings, for not a single nail or piece of metal enters into its composition.
The wheel consists of two rims of unequal diameter, of which the one next the bank is rather the least. - “This double wheel,” observes Staunton, “ is connected with the axis by sixteen or eighteen spokes of bamboo, obliquely inserted near each extremity of the axis, and crossing each other at about two-thirds of their length. They are there strengthened by a concentric circle, and fastened afterwards to the rims; the spokes inserted in the interior extremity of the axis (or that next to the bank) reaching the outer rim, and those proceeding from the exterior extremity of the same axis reaching the inner and smaller rim. Between the rims and the crossings of the spokes is woven a kind of close basket-work, serving as ladle-boards," which are acted upon by the strong current of the stream, and turn the wheel round.
The whole diameter of the wheel being something greater than the height of the bank, about sixteen or twenty hollow bamboos, closed at one end, are fastened to the circumference, to act as buckets. These, however, are not loosely suspended, but firmly attached with their open mouths towards the inner or smaller rim of the wheel, at such an inclination that when dipping below the water their mouths are slightly raised from the horizontal position; as they rise through the air their position approaches the upright sufficiently near to keep a considerable portion of the contents within them; but when they have reached the summit of the revolution the mouths become enough depressed to pour the water into a large trough placed on a level with the bank to receive it. The impulse of the stream on the ladle-boards at the circumference of the wheel, with a radius of about fifteen feet, is sufficient to overcome the resistance arising from the difference of weight between the ascending and descending, or loaded and unloaded, sides of the wheel. This impulse is in