The great eastern vault, the Garret, which is only 19 feet below the level of the entrance, does not fall, as stated by M. Martel, towards a series of choked swallets, that originally carried the waters farther down, but rises towards inlets from the surface. Its fretted roof has fallen in at the upper end. A little to the south is a nameless series of charming vestibules, grottoes, and tunnels, meandering towards the insignificant lakelet called the "River." Here we spent the whole of our first day. It is possible, we learned, to reach the easternmost series of caverns by this route, which also takes one into the square cavity designated as "Cust's Cave" on M. Martel's chart. We chose the other way, that is, through the passage from the "House of Lords" to the "Cathedral." In the tangle of contrary passages into which this leads we lost ourselves several times, in the absence of the guide, and only recovered the thread by careful observation with the compass. Eventually we found the way into "O'Leary's Cave," which struck us as one of the most impressive chambers in the whole cavern. It is not only much larger than is shown on the plan, but different in shape. Apparently it is the most recent of all in formation, although this may be only an appearance caused by the falling in of the roof. Unlike the other parts, where every bit of débris is sealed down by a glistening layer of stalagmite, this great cavity is heaped high with loose fragments, as free from incrustation as if the ceiling had collapsed yesterday. So wild and vast is the configuration of "O'Leary's Cave" that, standing on the lower side and looking across a depression in the middle to the ascending ground opposite, one fancied oneself, in the dim candlelight, gazing across a valley to a range of hills in the distance. We spent some time vainly searching for the horizontal tunnel supposed to end at the "Chimney," and before the guide joined us were lucky enough to hit upon a string of chambers that seem never to have been entered before. These run, so far as we could make out without actual measurement, right over the O'Callaghan series. In fact there were openings in the floor which we might have explored but for the aggressive and tenacious clay bedaubing everything, apparently leading down to these nether passages. Brilliant draperies swept down to the bold masses of stalagmite below the walls, and long crystalline wands hung from the roof in thousands, so that we could not move without committing havoc in this pendulous forest.