Botallack mine is not, I need scarcely say, a wheal Do-em. It is a grand old mine--grand because its beginning is enveloped in the mists of antiquity; because it affords now, and has afforded for ages back, sustenance to hundreds of miners and their families, besides enriching the country; because its situation on the wild cliffs is unusually picturesque, and because its dark shafts and levels not only descend to an immense depth below the surface, but extend far out under the bottom of the sea. Its engine-houses and machinery are perched upon the edge of a steep cliff, and scattered over its face and down among its dark chasms in places where one would imagine that only a sea-gull would dare to venture. Underground there exists a vast region of shafts and levels, or tunnels--mostly low, narrow, and crooked places--in which men have to stoop and walk with caution, and where they work by candlelight--a region which is measured to the inch, and has all its parts mapped out and named as carefully as are the fields above. Some idea of the extent of this mine may be gathered from the fact that it is 245 fathoms, (1470 feet), deep, and that all the levels put together form an amount of cutting through almost solid granite equal to nearly 40 miles in extent. The deepest part of the mine is that which lies under the bottom of the sea, three-quarters of a mile from the shore; and, strange to say, that is also the _driest_ part of the mine. The Great Eastern would find depth of water sufficient to permit of her anchoring and floating securely in places where miners are at work, blowing up the solid rock, 1470 feet below her keel--a depth so profound that the wildest waves that ever burst upon the shore, or the loudest thunder that ever reverberated among the cliffs, could not send down the faintest echo of a sound. The ladder-way by which the men descend to their work is 1230 feet deep. It takes half an hour to descend and an hour to climb to the surface. It was a bright morning in May when I walked over from Saint Just with Captain Jan to pay my first underground visit to Botallack. Arrayed in the red-stained canvas coat and trousers of the mine, with a candle stuck in the front of our very strong hats and three spare ones each hung at our breasts, we proceeded to the ladder-way. This was a small platform with a hole in it just big enough to admit a man, out of which projected the head of a strong ladder. Before descending Captain Jan glanced down the hole and listened to a distant, regular, clicking sound--like the ticking of a clock. "A man coming up," said he, "we'll wait a minute."