An insignificant crevice, a hole scarcely wide enough to tempt a dog or fox, alone gives admittance to what is perhaps the wildest and most magnificent cavern in Britain. Swildon's Hole, it has already been stated, lies at the same level, 780 feet above the sea, as the Eastwater Swallet and that of Hill Grove. It lies in a separate trough, within the same basin as the Eastwater stream, with whose waters it unites somewhere in the bowels of the rocky hills, to flow out of Wookey Hole as the river Axe, of which it may be considered as the principal feeder. A few years ago the actual swallet was visible, the brooklet running away into holes under a bank of earth and rock crowned with foliage. More recently, in order to make a small fish pond, the landowner has made a dam above the swallet, which is entirely concealed by this means, an entrance remaining, however, into the maze of cavities and waterways through a narrow crevice at the side. Mr. Balch was the first person to recognise the importance of Swildon's Hole as a chief feeder of the Axe, and in 1901 he made preparations to explore it. But through some delay, three members of his party were the first to enter the cave, without him--namely, Messrs. Troup and H. and F. Hiley. A short while after, Mr. Balch was able to carry out a more extended exploration. Then for some time no one entered the swallet, which gradually became choked with stones and litter brought down by the stream. Very few had ever heard of the cave, and hardly anyone realised that one of the most beautiful pieces of underground scenery in Britain was lying there unseen, and one of the most important of hydrological problems remaining quite unsolved. The next visit took place about Christmas 1904. Mr. Troup, who had been one of the first in the cave, took the lead of our party. My other companions were Messrs. Bamforth and E. E. Barnes, but we expected to be joined some hours later by Mr. Balch and Mr. Slater. When the first explorers entered this cavern some little while ago, they met with serious difficulties owing to the presence of ancient chokes or dams that held back pools of water, but they were assisted by the dryness of the weather. We, on the contrary, made our descent after a period of heavy rains, and the volume of water that accompanied us down was twentyfold as great. We had one advantage, however: the original discoverers were with us to point the way. With luggage reduced to a minimum, two ropes, plenty of illuminants, food, and two cameras, we passed through the uninviting entrance, and attacked methodically a close-packed mass of débris that had been washed into a narrow gut since the former visit.