So far, I had seen only one of these dreaded beings, from whom I had escaped with an ease which might not be repeated. How often, or at what times, they were likely to appear on the surface, I could not know, but I had learnt in that first dream-like interview, that the entrances to their excavations were of special danger, and I knew that these were not numerous. Anyway, I had no choice but to push forward. It was the more urgent because the claims of thirst and hunger were becoming unpleasantly assertive--indeed, at this time, had I crossed another of those subterranean entrances, I think I must have adventured down it at the call of this primal need, but no such opportunity came, and before the sun had reached its meridian, I saw the end of this stage of my journey. I had learnt, in my first instructions, that the path that led down to the grey beaches was one which must be traversed with the utmost rapidity. I did not guess its length, nor could I foresee that in all the strange and dreadful adventures which were before me, there would be few indeed to exceed its horror. I knew, from the depth of the gorge I had crossed, that I was high above the sea-level. I saw that the garden-ground (if such it were) sloped down, for many gradual miles, to an indistinct horizon. I looked continually for the break in that sea of pink and glossy green which would enable me to cross it. When it came, I did not see at first, my eyes being drawn to the steaming tank upon my other side. For here the cliff curved backward, giving space for an artificial lake of heated water, from which a steam rose continually, such as almost hid the cliffs upon the farther sides. I found it too hot to drink, but I filled a tin cup which my knapsack held, and waited for it to cool, till my thirst overcame me. It had a bitter and unpleasant taste, but I was in too great a need to be cautious. While I cooled a second cup at greater leisure I looked round and discovered that I had reached the place I was seeking. I saw, on my left, the entrance to a long straight tunnel sloping gently downward. This entrance was reached by a terraced drop in the opal roadway. The tunnel had a floor of yellow sand, which was divided by a narrow conduit down which an overflow from the heated tank ran smoothly, and very swiftly, owing to the slope at which it flowed. The sides of the tunnel were of a smooth grey material, not concave but flat, converging upwards, till they almost met at the top, but not quite, there being a slit of perhaps two inches dividing them, through which a certain amount of light entered the tunnel. It had a sinister appearance, and as I sat for a time regarding it, I considered what I might possibly have to fear if I should endeavour to penetrate it.