"And it was just as well they came back while we were off the main track," said Bob; "otherwise we might have had trouble."
Then they moved on along the middle track which they had been fortunate not to find at first, and for the space of several minutes not a word was spoken. There was no doubt about the hazardous nature of the mission on which they were employed; and Bob smiled grimly to himself as he reckoned up the chances against them, yet, strangely enough, each member of the expedition seemed in no wise to consider his own safety, and was fully determined to meet the best or worst that Fate had in store. A period had come in their lives when the call of the Unknown was irresistible; and had this for a moment failed them, the firm desire to rescue Emu Bill from the clutches of the savages would have sent them steadily onwards, recklessly ignoring the cost, for the wanderer's creed is simple and sincere—he may never forsake a comrade in deadly peril.
Their progress was painfully slow, for they knew not what obstacles might lie in their path, and probably it had been a miscalculation of their own pace that had led Mackay into error, when he turned into the drive along which he fancied he had heard the blacks approaching, for now the tunnel was distinctly curving to the left, and the occasional rush of fresh air which swept into their faces told them quite plainly that they were on the highway to the outside world. Slowly, too, the darkness began to merge into a gloom less and less profound, until the floor and sides of the cavern they traversed became dimly discernible.
"We won't be long now, my lads," encouraged Mackay.
"I is gettin' mighty nervous," murmured the Shadow, cheerfully. "I reckon I'll go back home. This ain't no place for a youth o' tender years, it ain't."
Bob laughed quietly at his companion's happy pessimism, and was about to make a reply when a faint buzzing sound in the unseen distance ahead drew his attention. Mackay, too, had heard it, and he stopped for an instant to listen more intently.
"What is it?" asked Jack, trying vainly to make out the cause of the vague noises.
"It's natives—at a distance, Jack, my lad," said Mackay. "They're outside the tunnel; so we'll be all right if there's no' too many o' them. I'm just hoping we've seen the full strength o' the tribe already."
They resumed their march; and now they had less difficulty in making progress owing to the continued increase of light, and as they proceeded the confused babel of voices became more and more distinct. The tunnel was by this time veering back towards its original course. Then suddenly a bright light flashed upon them as through a giant lens. The exit of the tunnel was in sight at last! Once more Mackay stopped, and was on the point of making some cautionary remark; but even while he turned the bright circle ahead was darkened, and several natives entered. A word at that moment might have proved disastrous, and Bob gripped Mackay's arm just in time; scarcely twenty yards separated them from their enemies. The big man hesitated only for a moment, then quickly concealed his rifle under his long cloak and walked slowly forward, his companions copying his example without a murmur.