In tracing the history of Ireland, Giraldus says [943] that about three hundred years after the Deluge four ponds suddenly broke forth from the bowels of the earth and that this was repeated at the time of the third colonization of Ireland under Neimhith.[944] Two ponds in Wales [945] were said to have burst their bounds and overflowed the neighborhood on the night of the death of Henry I. Before a great war, during which a province of central Wales was ravaged, a certain lake turned green, and old men described a similar portent just before the devastation of Wales by “Hoel, son of Moreduc” (Howel, son of Meredith).[946] The Lake of Brecknock in Wales appears sometimes a greenish color and sometimes ruddy as if penetrated by veins of blood.[947] Perhaps Giraldus was reminded of this by the mud-streaked appearance of mountain tarns after a rain, but it is less easy to explain the buildings, pastures, gardens, and orchards which he declares were occasionally visible beneath the surface. On the other hand, all who are familiar with inland waters in cold latitudes know the booming sounds they emit when frozen, which Giraldus compares to the moaning of a large herd of animals. These noises, he said, were caused by the sudden outrush of air imprisoned beneath the ice. At the top of Mount Snowdon, according to Giraldus, there are two lakes, one containing a floating island blown by the winds.[948] The most interesting lake with which Giraldus deals, however, is Lough Neagh in Ireland. This, he said,[949] lies in Ulster and is of remarkable size, thirty miles by fifteen. Though the relative proportions are right, the actual size is exaggerated, the dimensions being fifteen English miles long by from five to eight broad. The origin of the lake he attributed to an inundation that came as a punishment for the unnatural crimes of the natives of the region. This led him to a comparison of the story of Lough Neagh with the Biblical history of the destruction of the Pentapolis and the origins of the Dead Sea. The Dead Sea has always exerted a potent fascination over the minds of men. The uncanny natural features of its basin, and the terrible story associated with them, have been objects of curiosity from the very earliest times. Gervase of Tilbury goes into some detail on the subject.[950] The five cities, he says, were submerged, on account of the sins of their inhabitants, in a salt and sterile lake called the Dead Sea, where neither bird nor fish can live. The sea is open to no ship; nay, it even rises over everything not impregnated with bitumen, probably because of the living men within it. If any one by any means immerses a living creature in it, the living being immediately leaps out.[951] A burning torch will float on the lake, an extinct one will sink. There was certainly an infernal quality about the Dead Sea, and it was even supposed that beneath its waters there was an entrance into Hell.