“Up to this point a fellow would have had to double himself into a bowknot in order to lay down, and we’re not so very far from the shaft. I’ll go on a little further, and then if it hasn’t widened we might as well rejoin the others, because——”

The sentence was never finished, for at that instant Nelse felt the earth sink beneath him, and Gil’s coat was torn from his grasp as its owner plunged forward.

For a few seconds Nelse remained motionless, unable to understand what had happened, and then he realized that his companion must have been precipitated into a cavity of some kind, although the floor of the tunnel appeared firm when the whole party traversed it a few hours previously.

“Gil! Gil!” he called, and it seemed almost an endless while before the reply came:

“I’m all right, but I must have fallen twenty feet or more, and the breath was pretty nearly shaken out of my body.”

“What can I do to help you?”

“Get the rope and pull me out, for I don’t fancy staying here all night.”

“It doesn’t sound as if you were buried very deep.”

“I’m not buried at all, but simply in a big hole, which I don’t care to explore for fear of getting into worse trouble.”

By this time Nelse had collected his partially scattered senses, and at once made his way back to the shaft with all speed, startling the sailors into something very nearly resembling fear, as he hurriedly told what had befallen Gil.