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„ ] GIPSY-VANS ENCOUNTER DIFFICULTIES. 35 much facilitates the work, and the labourer, armed with a very short-handled pick, patiently hacks his vertical way, and sends up the earth by means of a basket and rope, drawn .by a primitive but effective windlass above, formed of a cradle of horizontal wooden bars. The man in charge simply turns the windlass without a handle, by clutching each successive bar, which, acting as a revolving lever, winds up the rope with the weight attached. The rapidity of the well-sinking naturally depends I, upon the quality of the soil ; if rock is to be cut / through, it is worked with a mason's axe and the cold ι chisel. Fortunately the geological formation is prini cipally sedimentary limestone, which offers no great I resistance. At length the water is reached. The I well is now left open for a few days that an opinion I. may be formed of the power ; if favourable, another precisely similar well is sunk at a distance of fifteen or j sixteen yards in the direction towards the point required I by the future aqueduct. The spring being satisfactory, the work proceeds with vigour. W e will accept the first well as forty feet in depth ; if the surface of the I earth were an exact level, the next well would be an equal depth ; but as the water retains its natural level, I the vertical measurement of each shaft will depend upon the formation of the upper ground. The object of the well-sinker is to create a chain of wells united by a subterranean tunnel, in order to multiply the power of a unit and to obtain the entire supply of water ; he therefore sinks perhaps ten or twenty wells to the same level, and he cuts a narrow tunnel from one to the other, thus connecting his shafts at the \vater-line, so as to form a canal or aqueduct. Pre , cisely as the mole upheaves at certain intervals the earth D 2

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