This figure [No figures in text] gives the general outlines of the chasm, without the minor cavities in the sides, of which there were several, each cavity having a corresponding protuberance opposite. The bottom of the gulf was covered to the depth of three or four inches with a powder almost impalpable, beneath which we found a continuation of the black granite. To the right, at the lower extremity, will be noticed the appearance of a small opening; this is the fissure alluded to above, and to examine which more minutely than before was the object of our second visit. We now pushed into it with vigor, cutting away a quantity of brambles which impeded us, and removing a vast heap of sharp flints somewhat resembling arrowheads in shape. We were encouraged to persevere, however, by perceiving some little light proceeding from the farther end. We at length squeezed our way for about thirty feet, and found that the aperture was a low and regularly formed arch, having a bottom of the same impalpable powder as that in the main chasm. A strong light now broke upon us, and, turning a short bend, we found ourselves in another lofty chamber, similar to the one we had left in every respect but longitudinal form. Its general figure is here given. The total length of this chasm, commencing at the opening _a_ and proceeding round the curve _b_ to the extremity _d_, is five hundred and fifty yards. At _c_ we discovered a small aperture similar to the one through which we had issued from the other chasm, and this was choked up in the same manner with brambles and a quantity of the white arrowhead flints. We forced our way through it, finding it about forty feet long, and emerged into a third chasm. This, too, was precisely like the first, except in its longitudinal shape, which was thus.