Conducted by the guide, we now descended the "Chimney" into the tortuous passages leading to the "Scotchman's Cave," which lies under O'Leary's. It is a small but very beautiful chamber, giving one the idea that it has been hollowed out in a mountain of Parian marble. Now we struck into the long series running east through "O'Callaghan's Cave" to the farthest point yet reached. This was one of the principal channels by which the ancient waters descended, from openings now unknown and inaccessible, to the labyrinth of forsaken waterways we had left behind. Our guide, who astonished us by the rapidity with which he got over difficult ground, was unable to make very speedy progress here. The ramifications are extremely hard to unravel, and he had only been in this part twice before, in 1895 with M. Martel, and twenty-five years earlier, as a boy, with his father. Eventually, after many wanderings, we reached "Brogden's Cave," where hitherto all direct progress had stopped. On the south side (not on the north, as shown in the chart) is the "Chapel," which M. Martel rightly described as the most beautiful thing in the whole cavern. It is an arched recess, canopied with stalagmite of the purest and most delicate lustre. Whilst my companion rested, I joined the guide, who was hunting for the passage to a cave where his father had taken him thirty-five years ago. We discovered the opening at last, and after wriggling and squirming round innumerable twists and corners, we dropped over a low cliff, beyond which a short wriggle brought us into a long and lofty cave, magnificently walled and pillared with snowy calcite. Floor, walls, and roof were a spotless white, wrought into intricate reliefs and embroideries by the flow of the freakish stalagmite. The guide stated that this was "Cust's Cave," and the one beyond, where our progress stopped, he called the "Demon's Cave." M. Martel's chart shows a "Cust's Cave" of a totally different shape and size, near the "River"; and, as there is no mention extant of any cave beyond Brogden's, I take it that this, the real Cust's, was unknown to him. Unfortunately I had followed the guide without bringing the plan or a compass, unaware that we were going so far from the known parts of the cavern; and now, to my disgust, the guide was unable to find the way out. Twice he descended into a hole at our end of the cave, and emerged with the intelligence, "It's not there, sir." We ransacked every opening in wall and floor, but failed to hit on any exit whatever. The guide grew alarmed, and rushed off to the farther end of the cave, wondering if we had completely lost our sense of direction. He tried whistling; but the hundreds of feet of rock between us and our companion were well able to guard their ancient silence. Tired with these exertions, he next proposed that we should put out the lights and rest for a while. Whether his idea was to husband the only provisions we had, I could not