"Sh—sh," came from the trapper.
Dick felt a gleam of hope, for instantly the boat shot ahead at redoubled speed. In spite of himself, the hand that directed the jacklight trembled. Gradually the sound grew more distinct; its nature puzzled the youth more and more.
"What in the world can it be?" he thought. "Crickets, it sounds funny. Wish I dared ask Hank."
But there was something in the boatman's manner which impelled silence.
They were skimming rapidly past the trees now. The boat shot ahead almost noiselessly toward the mysterious sound, which seemed to be just ahead.
Dick touched Dave on the shoulder.
"Wake up, wake up!" he whispered, excitedly.
"'Softly, oh, soft! Let us rest on the oar,'" murmured the stout boy. Then he sat bolt upright, with an exclamation, and peered ahead. "What's the——" he began.
But a low, stern injunction for silence from Hank Merwin cut him short.
Evidently something extraordinary was going on out there in the night.