uite right," approved Trendon. "I'll go down. Will you come with me,
sir?" he said to the captain.

They found Slade in profound slumber.

"Won't do to wake him now," growled Trendon. "Hello, what's here?"

Lying in the hollow of the sick man's right hand, where it had been
crushed to a ball, was a crumpled mass of tracing paper. Trendon smoothed
it out, peered at it and passed it to the captain.

"It's a sketch of an Indian arrow-head," he exclaimed in surprise, at the
first glance. "What are all these marks?"

"Map of the island," barked Trendon. "Look here."

The drawing was a fairly careful one, showing such geographical points as
had been of concern to the two-year inhabitants. There was the large
cavern, indicated as they had found it, and at a point between it and the
headland the legend, "Seal Cave."

"But it's wrong," cried Captain Parkinson, setting finger to the spot. "We
passed there twice. There's no opening."

"No guarantee that there may not have been," returned the other. "This
island has been considerably shaken up lately. Entrance may have been
closed by a landslide down the cliff. Noticed signs myself, but didn't
think of it in connection with the cave."

"That's work for Barnett, then," said the captain, brightening. "We'll
blow up the whole face of the cliff, if necessary, but we'll get at that
cave."

He hurried out. Order followed order, and soon the gig, with the captain,
Trendon, and the torpedo expert, was driving for the point marked "Seal
Cave" on the map over which they were bent.

VI

MR. DARROW RECEIVES

"You say the last entry is June 7th?" asked Barnett, as the boat entered
the light surf.

Trendon nodded.

"That was the night we saw the last glow, and the big burst from the
volcano, wasn't it?"

"Right."

"The island would have been badly shaken up."

"Not so violently but that the flag-pole stood," said the captain.

"That's true, sir. But there's been a good deal of volcanic gas going. The
man's been penned up for four days."

"Give the fellow a chance," growled Trendon. "Air may be all right in the
cave. Good water there, too. Says so himself. By Slade's account he's a
pretty capable citizen when it comes to looking after himself. Wouldn't
wonder if we'd find him fit as a fiddle."

"There was no clue to Ives and McGuire?" asked Barnett presently.

"None." It was the captain who answered.

The gig grated, and the tide being high, they waded to the