'We viewed a remarkable natural curiosity at Islam; two rivers bursting near each other from the rock, not from immediate springs, but after having run for many miles under ground. Plott, in his "History of Staffordshire", gives an account of this curiosity; but Johnson would not believe it, though we had the attestation of the gardener, who said, he had put in corks, where the river Manyfold sinks into the ground, and had catched them in a net, placed before one of the openings where the water bursts out. Indeed, such subterraneous courses of water are found in various parts of our globe.'