He let out his bellow, roaring Darrow's name.
"I doubt if you could project your voice far into a cave thus blocked," said Captain Parkinson. "We'll try this."
He drew his revolver and fired. The men listened at the crevices of the rock. No sound came from within.
"Your enterprise, Mr. Barnett," said the commander, with a gesture which turned over the conduct of the affair to the torpedo expert.
Barnett examined the rocks with enthusiasm.
"Looks like moderately easy stuff," he observed. "See how the veins run. You could almost blow a design to order in that."
"Yes; but how about bringing down the whole cave?"
"Oh, of course there's always an element of uncertainty when you're dealing with high explosives," admitted the expert. "But unless I'm mistaken, we can chop this out as neat as with an axe."
Dropping his load of cartridges carelessly upon a flat rock which projected from the water, he busied himself in a search along the face of the cliff. Presently, with an "Ah," of satisfaction, he climbed toward a hand's breadth of platform where grew a patch of purple flowers.
"Throw me up a knife, somebody," he called.
"Take notice," said Trendon, good-naturedly, "that I'm the botanist of this expedition."
"Oh, you can have the flowers. All I want is what they grow in."
Loosening a handful of the dry soil, he brought it
