' The first attempts to work this singular mine are said to have been made towards the beginning of the last century, when the small veins of tin were first observed to cross the rocky shoal which is exposed to view at low water. How long this first party of miners persevered in their difficult enterprise, and what were the mechanical aids of which they availed themselves, is not known; but the works, after being sunk to the depth of a very few fathoms in the rock, were abandoned.
About the year 1778 a poor miner in the parish of Breage, whose name was Thomas Curtis, had the boldness to renew the attempt. The distance of the shoal from the neighbouring beach at high water is about 1.20 fathoms; and this, in consequence of the shallowness of the beach, is not materially lessened at low water. It is calculated that the surface of the rock is covered about ten months in the year, and that the depth of water on it at spring tides is 19 feet. The prevailing winds occasion a very great surf here even in summer, but in winter the sea bursts over the rock in such a manner as to render all attempts to carry on mining operations unavailing.
Such were the difficulties which a poor individual had to surmount whose whole capital, perhaps, was not £10. As the work could be prosecuted only during the short period of time when the rock appeared above water (a period which was still further abridged by the necessity of previously emptying the excavation), three summers were consumed in sinking the pump shaft, a work of mere bodily labour. The use of machinery then became practicable, and a frame of boards being applied to the mouth of the shaft, it was cemented to the rock by pitch and oakum, made water-tight in the same way, and carried up to a sufficient height above the highest spring tide. To support this boarded turret—which was 20 feet high above the rock and 2 feet i inch square—against the violence of the surge, eight stout bars of iron were applied in an inclined direction to its sides, four of them below and four of an extraordinary length and thickness above. A platform of boards was then lashed round the top of the turret, supported by four poles, which were firmly connected with these rods. Lastly, upon this platform was fixed a winze for four men.
It was thought that the miners would thus be enabled to pursue their operations at all times, even during the winter months, whenever the weather was not particularly unfavourable ; but as soon as the excavation was carried to some extent in a lateral direction, this was found to be impossible; for the sea water penetrated through the fissures of the rock, and in proportion as the workings became enlarged, the labour of raising the waste to the mouth of the shaft increased. Curtis's predecessors, as well as himself, had carried on their excavations too near the surface, which not only made the rock more permeable, but less able to resist the immense pressure of water at high tide, so that it became necessary to support it with large timbers. To add to this disappointment it was found impossible to prevent the water from forcing its way through the shaft during the winter months, or, on account of the swell and surf, to remove the tin-stone from the rock to the beach opposite.
The whole winter, therefore, was a period of inaction ; it was not before April that the regular working of the mine could be resumed. Nevertheless.... '
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