“You heard it?”

“Yes; there again. Listen, captain.”

“I hear nothing.”

“No, it has stopped now.”

Captain Marsham made an impatient gesture.

“There!” cried Steve excitedly.

“Yes, there!” said Johannes. “You heard it then, sir?”

“No,” said the captain after a few moments’ listening. “You must both be mistaken.”

“No, sir,” said the Norseman gravely, “I am not mistaken; that was a steamer’s whistle.”

“Then it cannot be ours.”