“Ah!” sighed Mark, and there was silence again, broken this time by Dean.

“I can’t help it, Mark, old fellow. I have been trying so hard; but I must be a terrible coward. Tell me, oh, do tell me! Am I safe?”

The answer came faintly from apparently some distance away, in the shape of a sailor’s, “Ahoy–y–y–y!”

“Yes,” cried Mark excitedly. “That’s old Dan’s voice. They are looking for us. Ahoy–y–y–y!” he shouted, with his voice sounding strangely cracked and wild.

Quite a minute elapsed before they heard another hail, and by this time the two boys had pulled themselves together a bit, enough to respond with double the vigour of before, while ere many minutes had passed a steady interchange of calls made the task of the searchers so easy that the gleam of a lantern appeared, to be followed by the report of a gun, and this time there was a perfect volley of the strange echoes.

“Hear that?” cried Dean, in his natural voice.

“Hear it? Yes?”

Dean uttered a gasp as if he were swallowing something that was hard, and then with a laugh he said, “Mark, old chap, isn’t it queer! That seems to be the jolliest sound I ever heard in my life.”

“Yes,” said Mark coolly; “but we have got a long walk before us, and no end of stones to climb, and I expect we shall get into a precious row.”

“Never mind the row, old fellow. I wonder what they’ve got for supper!”