From "Rambles beyond Railways;" by W. Wilkie Collins, author of "Antonina."
MINING UNDER THE SEA.
In complete mining equipment, with candles stuck by lumps of clay to their felt hats, the travellers have painfully descended by perpendicular ladders and along dripping-wet rock passages, fathoms down into pitchy darkness; the miner who guides them calls a halt.
We are now four hundred yards out under the bottom of the sea, and twenty fathoms or a hundred and twenty feet below the sea level. Coast-trade vessels are sailing over our heads. Two hundred and forty feet beneath us men are at work; and there are galleries deeper yet even below that. The extraordinary position down the face of the cliff, of the engines and other works on the surface at Botallack, is now explained. The mine is not excavated like other mines under the land, but under the sea.
Having communicated these particulars, the miner next tells us to keep strict silence and listen. We obey him, sitting speechless and motionless. If the reader could only have beheld us now, dressed in our copper-colored garments, huddled close together in a mere cleft of subterranean rock, with flame burning on our heads and darkness enveloping our limbs, he must certainly have imagined, without any violent stretch of fancy, that he was looking down upon a conclave of gnomes.
After listening for a few moments, a distant unearthly noise becomes faintly audible,—a long, low, mysterious moaning, that never changes, that is felt on the ear as well as heard by it; a sound that might proceed from some incalculable distance, from some far invisible height; a sound unlike any thing that is heard on the upper ground in the free air of heaven; a sound so sublimely mournful and still, so ghostly and impressive when listened to in the subterranean recesses of the earth, that we continue instinctively to hold our peace, as if enchanted by it, and think not of communicating to each other the strange awe and astonishment which it has inspired in us both from the very first.
At last the miner speaks again, and tells us that what we hear is the sound of the surf lashing the rocks a hundred and twenty feet above us, and of the waves that are breaking on the beach beyond. The tide is now at the flow, and the sea is in no extraordinary state of agitation: so the sound is low and distant just at this period. But when storms are at their height, when the ocean hurls mountain after mountain of water on the cliffs, then the noise is terrific; the roaring heard down here in the mine is so inexpressibly fierce and awful that the boldest men at work are afraid to continue their labor; all ascend to the surface to breathe the upper air and stand on the firm earth; dreading, though no such catastrophe has ever happened yet, that the sea will break in on them if they remain in the caverns below.
Hearing this, we get up to look at the rock above us. We are able to stand upright in the position we now occupy; and, flaring our candles hither and thither in the darkness, can see the bright pure copper streaking the dark ceiling of the gallery in every direction. Lumps of ooze, of the most lustrous green color, traversed by a natural network of thin red veins of iron, appear here and there in large irregular patches, over which water is dripping slowly and incessantly in certain places. This is the salt water percolating through invisible crannies in the rock. On stormy days it spirts out furiously in thin continuous streams. Just over our heads we observe a wooden plug of the thickness of a man's leg; there is a hole here, and the plug is all that we have to keep out the sea.
Immense wealth of metal is contained in the roof of this gallery, throughout its whole length; but it remains, and will always remain, untouched: the miners dare not take it, for it is part, and a great part, of the rock which forms their only protection against the sea, and which has been so far worked away here that its thickness is limited to an average of three feet only between the water and the gallery in which we now stand. No one knows what might be the consequence of another day's labor with the pick-axe on any part of it. This information is rather startling when communicated at the depth of four hundred and twenty feet under ground. We should decidedly have preferred to receive it in the counting-house. It makes us pause for an instant, to the miner's infinite amusement, in the very act of knocking away about an inch of ore from the rock, as a memento of Botallack. Having, however, ventured, on reflection, to assume the responsibility of weakening our defence against the sea by the length and breadth of an inch, we secure our piece of copper, and next proceed to discuss the propriety of descending two hundred and forty feet more of ladders, for the sake of visiting that part of the mine where the men are at work.
Two or three causes concur to make us doubt the wisdom of going lower. There is a hot, moist, sickly vapor, floating about as, which becomes more oppressive every moment; we are already perspiring at every pore, as we were told we should, and our hands, faces, jackets, and trousers, are all more or less covered with a mixture of mud, tallow, and iron-drippings, which we can feel and smell much more acutely than is exactly desirable. We ask the miner what there is to see lower down. He replies, nothing but men breaking ore with pickaxes: the galleries of the mine are alike, however deep they may go; when you have seen one, you have seen all.