"I don't know what it is, but I am not taking any risks."

They hurried along the passage by which they had entered the cabin,
reached the hole in the bow by which they had entered and then, as
Percival turned on his flashlight, which he had extinguished after
entering the cabin aft, they hurried forward toward the hole in the rocks.

"There is no water here, Dick, at any rate," said Jack.

"No, there is not, but I can't think what made--hello!"

"What's the matter, Dick?"

"Where is the way up? I can't find it. The passage was not a wide one, was
it? We cannot have gone astray?"

"No, I don't see how we could," muttered Jack, as he looked around him,
the place being well lighted by Dick's flash. "Hello! I see what the
trouble is, and now I know what the noise was."

"Well?" asked Percival.

"Some of the rocks have fallen in, Dick. That was what made the noise.
Here is our rope. We are in the right place, therefore. The way up is
closed, however. Or, at any rate, it is closed here, but I don't
believe----"

"The rocks were not loose, were they, Jack?"