in a series of diminishing echoes, but no answer came, and he looked to his weapons, built up the fire with other fragments of wood that had been evidently borne in at times of flood, and explored the cave.  There was no sign of the woman anywhere, but he found three exits.  Relinquishing any idea of following them until Venning was fit to walk, he returned to the fire, and sat down with his back to the rock waiting for the woman’s return.  If he felt doubt or fear, he fought against it, resolving that, come what would, his first care was to save his companion, but that there was cause for doubt he knew very well from the remarks and bearing of the woman.  Probably, he thought, the secret of the underground was hers only, and she might well have a motive sufficiently strong to preserve that secret even at the sacrifice of their lives.  Full of these thoughts, he began another examination of the cave, confining himself this time to a search of the floor.  Going down on hands and knees, and carrying a lighted stick, he minutely inspected the thin layer of dust which had settled since the last flood-waters had rushed through.  Traversing slowly the width of the cave, he found his own spoor and the spoor of the woman.  Then working round with the object of finding which of the three openings she had taken on leaving, he came upon a calabash and a kaross made of goats’-skin.  The calabash, from the smell, contained goats’-milk.  Leaving the fire-stick to mark the spot to which he had carried his search, he went back to place the kaross over the sleeping boy.  Then taking another stick from the fire, he took up the spooring from the place he had left off, and crawled inch by inch, till he came to the first exit.  Here he saw his spoor entering together with the footprints of the woman, both very plain from the mud which had adhered to their feet.  The woman, however, had not passed out.  That, at any rate, was one point settled, and he went on with a feeling of distinct relief at the thought that there might be another way out than by the fearful track they had followed on entering.  On nearing the second exit he paused, startled by what seemed to him the sound of shrill voices borne suddenly in a pause between the bellowing of the water-jets in the neighbouring vault.  When he listened he could, however, distinguish no sound in the mutterings and the boomings that was human, and repressing a desire to cry out, he groped along up to the second exit.  Here, however, there were no footprints.  The surface was smooth rock, and he was passing on when something about the rock attracted his attention again.  Leaving one of the sticks again to guide him on his return by its glowing end, he returned to the fire, rebuilt it, waited till it was fairly blazing, then with another glaring torch he ran to continue his search.  He found what he had half expected, that the rock had been polished by the passage of many feet, which had worn out quite a marked depression.