In a moment something grim and sinister whirled and hissed through the air, and then there came a terrific explosion in the forest to the right. Trees were leveled, and a great hole showed in the bank. In an instant, following close on the roar of the dynamite, there came a chorus of cries from savage throats-cries of fear, of terror, of rage—and then silence.
For a moment it seemed as if the forests held no forms of animal life, then the sharp call of the tiger-cat, the wail of the puma, the chattering of the monkeys, came to the ears of the listening boys.
"I guess this coming act will consist of a feed for the wild beasts!" Jack said.
For a long time there was no sound of savage life in the forests, save that from the throats of beasts of prey, scenting blood and slowly drawing closer to the river's banks. The boys on the Black Bear looked into each other's faces and wondered.
"They didn't act that way when we exploded dynamite!" Jack said.
"No. They came right back at us!" Frank replied.
"I take it that they think there's something supernatural in this dropping of dynamite from the sky," Harry observed. "Anyway, they seem to have taken themselves off, and we'll open up and signal to the Nelson! Say, won't it be fine to see good old Ned Nestor again? I wonder how he knew we were here?"
"And I wonder where Jimmie and Leroy are?" Harry reflected. "There is only one person on the machine, and that must be Ned."
Jack was about to throw open the top panels when he caught sight of the aeroplane again, nearer to the water than before.
"What's Ned doing?" he asked, pointing upward.