Again the picture died out and again the old Krooman threw on more powder. As the smoke rolled up once more no one spoke. The situation was far too tense for that.
The scene now seemed to show that indeed all was over with the occupants of the canoe. The frail craft was seen to be in a tunnel of rough stone through which the roaring vortex of the waters poured with such violence that the boys and their aged companion were continually drenched with spray. Lathrop had hard work to keep the craft free of water now, and bailed incessantly. The old man was on his knees his hands clasped and his lips moving as if in prayer. Billy, his face set, sat in the stern. Again and again with a quick twist of his paddle he saved the canoe from annihilation in the boiling current.
It was an agonizing scene to watch, and to the onlookers it seemed as real as if they had been gazing at the peril itself instead of its counterfeit presentment in smoke-pictures.
At last the walls of the tunnel were seen to widen out and the current to move more slowly. Frank gave a sigh of relief which was echoed by the others as the canoe emerged from the subterranean river into a broad lagoon with low banks covered with tropical verdure and seemingly, from the absence of steaming vapors a healthy spot. But even as the canoe entered the quiet waters a great body projected itself through the water followed by three other bulky forms.
They were recognized instantly by the watchers as hippopotami.
The leader of the animals made straight for the canoe, and the watchers trembled as they looked, for it was evident that one snap of the creatures' huge jaws would cave in the side of the canoe as if it were an eggshell.
With trembling excitement the Boy Aviators saw their young companions with both paddles make desperately for the shore, but before they reached it one of the hippopotami intercepted them, and with a charge of angry fury literally tossed the boat clean out of the water.
A second later the gazers at the smoke pictures saw the two missing adventurers and their aged unknown companion struggling in the water. It seemed that all was over when a strange interruption occurred.
A long, dark horny head with two cruel eyes and rows of saw-like teeth in its long jaws, sped through the waters. The hippopotamus turned savagely on the intruder and the two snapped savagely at each other for several minutes when the crocodile, mortally wounded to judge by the red swirl on the surface of the stream, made off.
But Billy and Lathrop were seen to have taken advantage of the brief breathing spell it gave them. In a few strong strokes they had swum with the aged man to shallow water and quickly waded ashore. They were safe then for the time being. But for how long?