Running the gauntlet beneath another tributary, which came swishing in just over our heads, we pushed on into a high and ample chamber, where in times gone by a volume of water had accumulated in a sort of gigantic cistern. The rocky roof was flat and smooth, its cracks and fissures fringed with meandering lacework of stalactite. In front, the rocky mole that once held up the reservoir was cloven into a series of Limestone seracs, between which the stream found its way down into the remoter cavities. Masses of clay, some 15 feet thick, deposited by the ancient waters, still flanked this rugged portal into the unknown. Bones of sheep, cattle, horses, and lesser mammals lay about in profusion, enough to reconstruct whole skeletons; with them were the relics of animals now extinct on Mendip, deer and other creatures. Higher up sherds of Samian pottery had been found, brought down by the stream from the rubbish heaps of long ago. What struck the imagination as still more wonderful was that in this sunless spot, 300 feet below the surface, there were creatures that lived. Empty snail shells were abundant, but yet more plentiful were tiny snails that were actually crawling over the clay, feeding, no doubt, on water-borne vegetable matter. Gossamer-like webs stretched across many chinks in the Limestone, but the microscopic spiders we could not see. What flies did they live on? Surely not the caddis, whose corpses lay about in plenty on every shoal. From this chamber the stream quickly descends into the great Water Rift, one of the most wonderful things in the whole cavern. It is but a few feet wide, but its height is enormous. The walls go up like mountain cliffs, but are lost in gloom instead of mist. Here tremendous changes had taken place since the former exploration. At that time the rift was blocked up in one place by a vast barrage of rock and stalagmite, that came down to the stream and forbade human progress save by one strait and difficult way. At a height above the water a hole ascended seven feet into the barrier, its orifice all but closed by a fringe of stalactites. Contriving to enter, the explorers crept up this pipe, and down a corresponding one on the other side, coming out on a cliff face overhanging the continuation of the Water Rift, to attain the bottom of which was an abstruse gymnastic problem. A little farther on they reached the utmost limit of their journey, where the stream beats violently against the termination of the rift, is hurled sideways, and finds an outlet through a low crevice, whence it tumbles in a 40-foot cataract into an unknown pool. Our main object to-day had been to descend this 40-foot pitch; that was the reason why we had encumbered ourselves with two long ropes. But now all was different. In the short interval that had elapsed since the former visit, the strength of the ungovernable torrent had swept away the whole of this vast structure, the work of thousands of ages--for the Pyramids are