He shook his head. "No," said he, "I don't think that, at all. The distance we came up didn't seem half as far as the distance we went down; an' you'll notice there ain't any outside entrance to this cavern whatever. It's a reg'lar dome over this pool o' water, and unless there's some passage at the back, up yonder, we're fast pris'ners."

Trot looked thoughtfully over her shoulder.

"When we're rested," she said, "we will crawl up there and see if there's a way to get out."

Cap'n Bill reached in the pocket of his oilskin coat and took out his pipe. It was still dry, for he kept it in an oilskin pouch with his tobacco. His matches were in a tight tin box, so in a few moments the old sailor was smoking contentedly. Trot knew it helped him to think when he was in any difficulty. Also, the pipe did much to restore the old sailor's composure, after his long ducking and his terrible fright—a fright that was more on Trot's account than his own.

The sand was dry where they sat, and soaked up the water that dripped from their clothing. When Trot had squeezed the wet out of her hair she began to feel much like her old self again. By and by they got upon their feet and crept up the incline to the scattered boulders above. Some of these were of huge size, but by passing between some and around others, they were able to reach the extreme rear of the cavern.

"Yes," said Trot, with interest, "here's a round hole."

"And it's black as night inside it," remarked Cap'n Bill.

"Just the same," answered the girl, "we ought to explore it, and see where it goes, 'cause it's the only poss'ble way we can get out of this place."

Cap'n Bill eyed the hole doubtfully

"It may be a way out o' here, Trot," he said, "but it may be a way into a far worse place than this. I'm not sure but our best plan is to stay right here."

Trot wasn't sure, either, when she thought of it in that light. After awhile she made her way back to the sands again, and Cap'n Bill followed her. As they sat down, the child looked thoughtfully at the sailor's bulging pockets.

"How much food have we got, Cap'n?" she asked.

"Half a dozen ship's biscuits an' a hunk o' cheese," he replied. "Want some now, Trot?"

She shook her head, saying:

"That ought to keep us alive 'bout three days if we're careful of it."

"Longer'n that, Trot," said Cap'n Bill, but his voice was a little troubled and unsteady.

"But if we stay here we're bound to starve in time," continued the girl, "while if we go into the dark hole—"