As in many other bone-caverns, the underground passages and channels were generally found floored with a layer of stalagmite, varying in thickness from one to fifteen inches, and next below occurred loam or bone-earth from two to fifteen feet in thickness. In the latter were found remains of the mammoth, of the cave-bear, of the cave-lion, and other extinct mammalia. No human bones were obtained, but many flint knives, chiefly from the lowest part of the bone-earth, and one of the most perfect lay at the depth of thirteen feet from the surface, and was covered with bone-earth of that thickness.
At one point in the overlying stalagmite a perfect reindeer’s horn was found sticking, and in another an entire humerus of the cave-bear—a convincing proof that both these animals must have lived after the flint tools were manufactured, or in other words that man in this district preceded the cave-bear. ‘A glance at the position of Windmill Hill, in which the caverns are situated, and a brief survey of the valleys which bound it on three sides, are enough to satisfy a geologist that the drainage and geographical features of this region have undergone great changes since the gravel and bone-earth were carried by streams into the subterranean cavities. Some worn pebbles of hematite, in particular, can only have come from their nearest parent rock at a period when the valleys immediately adjoining the caves were much shallower than they now are. The reddish loam in which the bones are embedded is such as may be seen on the surface of limestone in the neighbourhood, but the currents which were formerly charged with such mud must have run at a level seventy-eight feet above that of the stream now flowing in the same valley.’[32]
In 1861, Colonel Wood found, in a newly discovered cave of the peninsula of Gower, in Glamorganshire, the remains of two species of rhinoceros, R. teichorhinus and R. hemitœchus, in an undisturbed deposit, in the lower part of which were some well-shaped flint knives, evidently of human workmanship. This is the first well-authenticated example of the occurrence of human implements in connexion with R. hemitœchus—the first proof that this extinct brute, elsewhere the usual companion of the mammoth, has been coeval with man.