But while they stood thus deliberating as how best to surmount the difficulty, the dreaded sound of approaching natives fell dully on their ears. The Shadow uttered a stifled groan and his rifle-lock clicked under his impetuous fingers. Jack gave a faint whistle of dismay, and Bob calmly drew and cocked his revolver. Mackay stood unmoved, straining his eyes into the gloom; then he gently pressed Bob back close to the wall.
"Hug the side," he whispered; and each one crushed hard against the slimy rock, and waited.
Pat! pat! pat! came the unwelcome echoes, accompanied by an occasional splash, as the oncoming band floundered in the mire, and the direction from which the disturbance came was away decidedly to the left, although it was speedily altering to a point straight ahead. Bob noted this fact carefully, despite his alarm.
Nearer and nearer the unseen band advanced until but a few yards separated them from the yawning pit. Bob held his breath. Would they walk blindly into it? Had they miscalculated its position? He felt Mackay's hand press lightly on his shoulder as if to give him confidence, and he marvelled at its steadiness, and braced himself for the encounter he felt sure was about to begin. He could hear Jack's heart throbbing under the severe tension of the moment, and the Shadow's quick breaths indicated how trying was the strain even for that iron-nerved youth. But now came the crucial moment; the foremost savage shrieked out a guttural word of warning, as it seemed, and stopped, apparently on the edge of the chasm. A second later and his feet alighted with a sharp, sliding sound close opposite Bob, and with a recovering effort he passed on. He was followed immediately by another and still another warrior, whose arrows rustled in their hands as they cleared the gulf. If one of them had slipped there could have been little hope of escape for the intrepid quartet, for assuredly the slightest stumble would have sent him right into their arms. But no disaster of the kind occurred, each wildly-leaping figure arrived safely on the slippery floorway beside them and lunged forward with the momentum of his flight, and in this way fifteen warriors passed and proceeded on their way; then all was quiet again.
Mackay broke the silence. "That was a close shave, my lads," said he, coolly. "Now, I wonder if any of you noticed how they got across so sprightly?"
"I reckon they jumped," grunted the Shadow, "an' I is mighty pleased they jumped so well."
"It would be a good jump," whispered Bob; "but they cleared it too easily without a run."
"I think I'll risk lighting a match," said Mackay. "There's a bend in the tunnel straight forward a bit, so nothing can be seen past that, an' the niggers that have passed will probably be dodgin' the barrel o' Never Never's rifle by this time."
A howl of terror from that extremity of the tunnel almost verified his surmise. Mackay calmly struck a match, held it aloft for an instant, and blew it out hurriedly, but in that fleeting moment Bob caught sight of a stout rope suspended from a beam directly over the pit, and he also observed that at this point the roof of the tunnel was considerably farther above them than it had been at the start of their journey. Evidently, greater work of excavation had been done at this part of the golden lode. Mackay groped forward and seized the rope, gave it a tug to test its strength, then swung himself lightly across the obstacle which had delayed them so long. Bob went next, then Jack and Shadow trusted their weight to the flying trapeze.
"They might just as well have put a log or two across that shaft," murmured Mackay.