A huge fire blazed in the opening of their rocky shelter that the prowling carnivora might be kept at bay; and always one man stood on guard, watchfully alert against a sudden rush by some maddened beast of the jungle. Beyond the fire, yellow-green spots of flame appeared, moved restlessly about, disappeared and reappeared, accompanied by a hideous chorus of screams and growls and roars as the hungry meat-eaters hunting through the night were attracted by the light or the scent of possible prey.

But to such sights and sounds as these the five men had become callous. They sang or talked as unconcernedly as they might have done in the bar-room of some publichouse at home.

Sinclair was standing guard. The others were listening to Brady's description of traffic congestion at the Rush Street bridge during the rush hour at night. The fire crackled cheerily. The owners of the yellow-green eyes raised their frightful chorus to the heavens. Conditions seemed again to have returned to normal. And then, as though the hand of Death had reached out and touched them all, the five men tensed into sudden rigidity.

Above the nocturnal diapason of the teeming jungle sounded a dismal flapping of wings and over head, through the thick night, a shadowy form passed across the diffused light of the flaring camp-fire. Sinclair raised his rifle and fired. An eerie wail floated down from above and the apparition, whatever it might have been, was swallowed by the darkness. For several seconds the listening men heard the sound of those dismally flapping wings lessening in the distance until they could no longer be heard.

Bradley was the first to speak. "Shouldn't have fired, Sinclair," he said; "can't waste ammunition." But there was no note of censure in his tone. It was as though he understood the nervous reaction that had compelled the other's act.