was possible, by driving an adit from a lower point, to let off the water by natural drainage. But this was not often found practicable, and in most cases it had to be raised directly from the shafts by artificial methods. As the quantity increased, a whim or gin moving on a perpendicular axis was employed to draw the water.[25] An improvement on this was the rack and chain pump, consisting of an endless iron chain mounted with knobs of cloth stiffened with leather, inclosed in a wooden pump of from six to eight inches bore, the lower part of which rested in the well of the mine. The chain was turned round by a wheel two or three feet in diameter, usually worked by men, and the knobs with which it was mounted brought up a stream of water according to the dimensions of the pump. Another method, considered the most effectual of all, was known as “the water-wheel and bobs,” consisting of a powerful pump, or series of pumps, worked by a water-wheel. But although there is no want of water underground in Cornwall, and no want of rain above ground, there are few or no great water-courses capable of driving machinery; besides, as the mines are for the most part situated on high ground, it will be obvious that water-power was available to only a very limited extent for this purpose. [25] Mr. Davies Gilbert says even this method was comparatively modern, as he remembered a carpenter who used to boast that he had assisted in making the first whim ever seen westward of Hayle.--Davies, ‘Parochial History of Cornwall,’ London, 1838, ii. 83.