When the three had gone, moving eastward along the foot of that towering stone wall, I began where the water came tumbling out of that hole in the cliff, and carefully examined the banks of the creek again, up and down, for half a mile or so. I reasoned that if he waded into the stream he must certainly have waded out of it again. Unless, as Norris had conjectured, he had swung himself over the bank by the means of some liana. I therefore imitated Norris and searched both sides for evidence of any such means; and with a negative result. Nowhere, so far as the forest followed the stream, was there a loose liana near the bank on either side.
And then it came to me that perhaps Duran had gone into the water at the end of the path, only to retrace his steps and leave the path some way on the back trail, thus to deceive any who should chance to come so far on his track. And so I scrutinized every foot of the path back to the edge of the forest, and some way across the glade. I even went off the trail, and fought my way through the growth as I went back, paralleling the path, and looking for signs.
But I got back to the creek bank and the music of the little cascade, no nearer the solution than when I had started. Hours had been consumed in my search. It must have been past ten when I squatted on the stream's bank, looking into the clear water, puzzling over this thing.
A beam of sun shone down through the water and illumined the creek's bottom. A round bit of rock or coral lay there, almost white in that liquid light. For a long time I stared on that spot, as if the solution were to be found there. I never before had felt so baffled.
And then I was startled! I could no longer see that stone—nor any part of the creek's bed. The water had in that moment become turbid. Something had muddied it. I leaped to my feet and hurried up to the fountain in the cliff. The water was coming out of the rock in that muddied condition. Now what could it all mean? I asked myself. And I set my wits to the thing as I continued to stare at the phenomenon. Presently the water cleared a bit. And then in a little it came as muddy as ever again.
CHAPTER XXIII
WHAT THE WATER HID
My thoughts flew. In a moment more I thrilled with an idea. Then I dashed into the water and got myself up to the little waterfall, made, as I have said, by a portion of the water coming round a rock and flowing over the edge of a flat shelf of rock.
I tried to look through that thin veil of liquid, failing which, I braved a shower and put my head through. In another moment I had my whole body behind that little cascade. I crouched, sputtering, under the rocky shelf. Then for eight or ten feet I crawled forward in the darkness. Directly, the passage made a little turn to the right, and the ground under my hands sloped upward. It may have been fifty feet, it may have been a hundred and fifty feet, that I had penetrated that cliff—my excitement had taken no measure of the distance—when I found that I could no longer feel the wall on either side. I was in a cavern of unknown dimensions.