I had noticed for some time that the floor of the tunnel was ascending, and it seemed to me steeper than I had thought it to be when I came the other way; but I paid little heed to this, because a hill always seems steeper when you ascend than when you descend. But all of a sudden I felt that the inclination was downward, and I was trying to recollect if I had gone up and then down as I came from the cavern, when I felt something cold about my feet, and, taking a step forward, splashed in water. Instantly I turned about and rushed back, stumbling and falling, and in a great dismay, for I knew now that I had lost my bearings. There had been no water in the passage when I came; either water had rushed into it suddenly, though how that could be I knew not, or else I had come into another passage. Whichever it might be, my situation was exceeding serious, for I might be drowned, or I might wander for hours and never come to the cavern. I picked myself up when I fell in my haste, and as I leant against the wall to recover myself, something scurried past my feet, which made me shiver until I thought that it could not be more than a rat or some other small beast. But being now so confused that I knew not whether I had come from right or left, I lifted up my voice and shouted the seaman's call "Ahoy!" for if I was anywhere near the cavern, Billy might hear me, and that familiar word would bring him, I did not doubt, to my help. I was startled by what ensued upon my shout, for the whole space about me was filled with noise, which at first I did not know to be the reverberation of my own voice. The noise, the like of which I suppose had never been heard in that place before, terrified all the denizens of it, and I felt several small animals brush against my legs as they scurried past. When the sounds had rolled away, I listened very intently for some answering cry, but there was none, even though I shouted again, and I could not but conclude that the din, great as it was, had failed to reach Billy's ears. And since it now seemed plain that I must depend on myself alone, and to stay still where I was would not help me a jot, I began in sheer desperation to grope my way along the passage, not knowing in the least whether I was going right or wrong. But supposing that I had overshot the entrance to the passage leading back to the cavern, and that I was now retracing my steps, I crept along by the wall on my left hand, every now and again stopping to shout and listen, but always in vain. And it came into my mind presently that while the sound of my voice might carry a good way along the portion of the tunnel in which I then was, yet it would not penetrate far along the passage that ran back at a very sharp angle from it, so that I would do better to save my breath until I arrived at the fork, and I went on again, holding my peace.