"At Tin-y-coed I found a credulous farmer ruining himself in excavating a horizontal gallery in search of coal, an ignorant miner being his engineer. The case may serve as a striking example of the _coal-boring_ mania in districts which cannot by possibility contain that mineral; and a few words concerning it may, therefore, prove a salutary warning to those who speculate for coal in the Silurian Rocks. The farmhouse of Tin-y-coed is situated on the sloping sides of a hill of trap, which throw off, upon its north-western flank, thin beds of black grauwacke shale, dipping to the west-north-west at a high angle. The color of the shale, and of the water that flowed down its sides, the pyritous veins, and other vulgar symptoms of coal-bearing strata, had long convinced the farmer that he possessed a large hidden mass of coal, and, unfortunately, a small fragment of real anthracite was discovered, which burnt like the best coal. Miners were sent for, and operations commenced. To sink a shaft was impracticable, both from the want of means, and the large volume of water. A slightly inclined gallery was therefore commenced, the mouth of which was opened at the bottom of the hill, on the side of the little brook which waters the dell. I have already stated that, in many cases, where the intrusive trap throws off the shale, the latter preserves its natural and unaltered condition to within a certain distance of the trap; and so it was at Tin-y-coed, for the level proceeded for 155 feet with little or no obstacle. Mounds of soft black shale attested the rapid progress of the adventurers, when suddenly they came to a 'change of metal.' They were now approaching the nucleus of the little ridge; and the rock they encountered was, as the men informed me, '_as hard as iron_,' viz., of lydianized schist, precisely analogous to that which is exposed naturally in ravines where all the phenomena are laid bare. The deluded people, however, endeavored to penetrate the hardened mass, but the vast expense of blasting it put a stop to the undertaking, not, however, without a thorough conviction on the part of the farmer, that, could he but have got through that hard stuff, he would most surely have been well recompensed, for it was just thereabouts that they began to find '_small veins of coal_.' It has been before shown, that portions of anthracite are not unfrequent in the altered shale, where it is in contact with the intrusive rock. And the occurrence of the smallest portion of anthracite is always sufficient to lead the Radnorshire farmer to suppose that he is very near 'El Dorado.' Amid all their failures, I never met with an individual who was really disheartened; a frequent exclamation being, 'O, if our squires were only men of _spirit_, we should have as fine coal as any in the world!'"--(_Silurian System_, Part I., p. 328.)]