In her voice there was such pleading, and in her face such pain, that I had to make the promise. Yet I am ashamed to say that, even at the time, I suspected that I should not abide by my word. * * * * * Meanwhile the mystery of Yulada was not the only shadow that had thrust itself across my mind. As I gradually regained the use of my limbs, I began to be troubled by thoughts of the future; I recognized how great was my debt to the natives; and was ashamed at thought of accepting their hospitality without making any return. Yet the prospects were that I should remain with them for more than a few days or weeks. My fellow geologists had doubtless given me up long ago as lost; and there was no telling how many months would pass before I could find my way out of this wilderness. To attempt to wander unguided among the mountain labyrinths would be suicidal; and I not only had no way of knowing how far it was to the nearest civilized settlement or trade route, but could obtain no information from my hosts. Reluctantly I admitted to myself that I was marooned. And although the spell of Sobul was already upon me, I was not so captivated that I did not dream of escape. True, it would have caused me a pang to leave the kindly mountain folk, and particularly Yasma, but what could this count against my life-work, the remembrance of my friends in America, and all the arts and allurements of civilization? Yet what could I do to escape? After long reflection, only one project had occurred to me--and that unpromising enough. Though the other geologists had certainly gone long ago, might they not have left some message for me in the hope that I was yet alive? Yes, even a message instructing me how to escape? Meager as the chances were, would it not at least be worth while to revisit the site of our former camp? Somewhat doubtfully, I consulted the natives. But they regarded my suggestion as quite natural, and several volunteered to accompany me across the mountains as soon as I was strong enough. It was early September, more than seven weeks after my arrival in Sobul, when at last I was ready for the expedition. Accompanied by three of the Ibandru, I started out along a slender trail that ran straight toward the jutting northern slope of "The Mountain of Vanished Men." But these three were quickly increased to four; we had hardly started when an auburn-haired girl came tripping behind us, joining us in defiance of the scowls of the men. For my own part, I was far from displeased at her presence; with her gleaming eyes to encourage me, I found it just a little easier to accomplish the abrupt and perilous climb. And both perilous and abrupt it was, for when we were not crawling on hands and knees up gigantic broken natural stairways of rock, we were winding single-file in long horseshoe curves between a precipice and a cliff, or skirting the treacherous verge of a glacier.