I could scarcely believe my eyes as I ran towards it, and doubts of a mirage haunted me. But it was no mirage, but a real lake, perhaps three miles in circumference, with bracken-fringed banks, a shore of white pebbles, and clear deep blue water. I drank my fill, and then stripped and swam in the blessed coolness. After that I ate some luncheon, and sunned myself on a flat rock. “I have discovered the source of the Labongo,” I said to myself. “I will write to the Royal Geographical Society, and they will give me a medal.” I walked round the lake to look for an outlet. A fine mountain stream came in at the north end, and at the south end, sure enough, a considerable river debauched. My exploring zeal redoubled, and I followed its course in a delirium of expectation. It was a noble stream, clear as crystal, and very unlike the muddy tropical Labongo at Umvelos’. Suddenly, about a quarter of a mile from the lake, the land seemed to grow over it, and with a swirl and a hollow roar, it disappeared into a mighty pot-hole. I walked a few steps on, and from below my feet came the most uncanny rumbling and groaning. Then I knew what old Coetzee’s devil was that howled in the Rooirand. Had I continued my walk to the edge of the cliff, I might have learned a secret which would have stood me in good stead later. But the descent began to make me anxious, and I retraced my steps to the top of the chimney whence I had come. I was resolved that nothing would make me descend by that awesome crack, so I kept on eastward along the top to look for a better way. I found one about a mile farther on, which, though far from easy, had no special risks save from the appalling looseness of the _débris_. When I got down at length, I found that it was near sunset. I went to the place I had bidden my native look for me at, but, as I had feared, there was no sign of him. So, making the best of a bad job, I had supper and a pipe, and spent a very chilly night in a hole among the boulders. I got up at dawn stiff and cold, and ate a few raisins for breakfast. There was no sign of horses, so I resolved to fill up the time in looking for the fold of the cliff which, as I had seen from the horrible crack of yesterday, contained a gully. It was a difficult job, for to get the sidelong view of the cliff I had to scramble through the undergrowth of the slopes again, and even a certain way up the kranzes. At length I got my bearings, and fixed the place by some tall trees in the bush. Then I descended and walked westwards. Suddenly, as I neared the place, I heard the strangest sound coming from the rocks. It was a deep muffled groaning, so eerie and unearthly that for the moment I stood and shivered. Then I remembered my river of yesterday. It must be above this place that it descended into the earth, and in the hush of dawn the sound was naturally louder. No wonder old Coetzee had been afraid of devils. It reminded me of the lines in _Marmion_— “Diving as if condemned to lave