It was only a noise, but a noise such as Lennox felt that he must hear-- a low, dull, harsh, grating noise as of stone passing over stone; and though he could see nothing with his eyes, mentally he knew that one of the great time-bleached and weathered blocks of granite that helped to form the cyclopean face of the kopje wall had begun to turn as on a pivot. This grating sound lasted for a few seconds only, and it came apparently from a couple of yards away to his right, as he stood with his back pressed against the rugged natural stones. Then the noise ceased as suddenly as it had begun, and he listened, now holding his breath in the vain hope that it would silence the heavy, dull beating of his heart, whose throbs seemed to echo painfully in his brain. He pressed Dickenson's hand again, to feel from the return grip how thoroughly his comrade was on the alert. Then all was perfectly silent again, while a dull feeling of despair began to assert itself as he felt that they were going to hear no more. At last, with head wrenched round to the right, his revolver feeling wet in his fingers and his eyes seeming to start with the strain of gazing along the shelf at the brilliant stars before him, his nerves literally jerked and he felt perfectly paralysed and unable to stir, for here, not six feet away, he could make out against the starry sky the dimly-marked silhouette of a heavily-built man. CHAPTER FOURTEEN. A STRANGE FIND. It seemed to Drew Lennox that he was staring helplessly at the dark shadowy shape for quite a minute--but it was only a matter of a few seconds--before, snatching his left hand from his companion's grasp, he let his revolver drop to the full extent of its lanyard, and sprang open-handed at the man. The movement warned the latter of his danger, and turning sharply round from where he was watching the direction taken by the detachment, he made a desperate effort to catch the young officer by the throat. But Lennox was springing at him, and the weight of his impact drove the man back for a yard or two; but he recovered himself, got a grip, and then a desperate struggle commenced at the edge of the rugged shelf of rock just where the kopje went down for some fifty feet almost perpendicularly, while a pile of heaped-up fragments which had lodged after falling from above stood out ready to receive the unfortunate who fell. Neither spoke as they gripped, but stood panting heavily as if gathering breath for the terrible struggle that threatened death to one if not both combatants. They were not well matched. Lennox seemed to be slightly the taller, but he was young, slight, and not fully knit; while his adversary was broad-shouldered, and possessed limbs that were heavily coated with hardened muscles, so that in spite of the weight brought to bear in the young officer's sprint he recovered himself where a weaker man must have been driven backward to the ground.