Old Tunnel and Giant's Chapel, two fine cave-rooms, were next explored. On entering the latter, Bob favored us with the rehearsal of an old story from the Arabian Nights, which--unfortunately, not one which will bear repetition--he wished us to believe actually happened in this very locality. I may here confess that, when we came to 'the dark hole in the ground,' I felt some slight reluctance to trust myself therein. Bob, observing this, immediately drew from his lively imagination such an astonishing increase of the perils of the way, looking complacently at me all the while, that my alarm, strange to say, took flight at once, and I pushed onward defiantly. The journey is, however, one that might justly inspire timidity. Above our heads, and on each side, frowned immense rocks, threatening at every instant to fall upon us; while the dash and babble of a stream whose course we followed, increasing in volume as we progressed, came to our ears like the 'sound of many waters.' We crossed this stream a hundred times, at least, in our journey. Sometimes it murmured and fretted in a chasm far below us; again, it spread itself out in our very path, or danced merrily at our side, until it seemed to plunge into some distant abyss with the roar of a cataract. We emerged from the windings of our tortuous path into Harlem Tunnel, a room six hundred feet in length. In its sides were frequent openings, leading into hitherto unexplored parts of the cave; but we did not venture to enter many of these. Never have I seen such rocks as we here encountered; at one time piled up on one another, ready to totter and fall at a touch; at another, jutting out in immense boulders, sixty feet above our heads, while, in the openings they left, we gazed upward into darkness that seemed immeasurable. From Harlem Tunnel we came into Cataract Hall, also of great length, and remarkable for containing a small opening extending to an unknown distance within the mountain, since it apparently cannot be explored. Applying the ear to this opening, the sound of an immense cataract becomes audible, pouring over the rocks far within the recesses of the mountain, where the Creator alone, who meted out those unseen, sunless waters, can behold its beauty and its terror. Crossing the Pool of Siloam, whose babbling waters sparkled into beauty as we held our lamps above them, we entered Franklin Hall. Here the roof, although high enough in some places, is uncomfortably low in others; whereupon Bob bade us give heed to the caution of Franklin, 'Stoop as you go, and you will miss many hard thumps.' We arrived next at Flood Hall, where a party of explorers were once put in great peril by a sudden freshet in the stream. They barely saved themselves by rapid flight, the water becoming waist-deep before they gained the entrance. We had no reason to doubt the truth of this story, as there were evidences of the rise and fall of water all about us.