“Come in!” growled Bob Hampton. “Here’s the cook brought your shaving-water, sir.”

The tapping was repeated, and sounded some little distance off.

“Answer them, whoever it is, Bob,” I said; for this seemed to be something, if not tangible, at all events certain.

There was a little rustling about, and the tapping came again.

“Why don’t you answer them?” I said tetchily.

“What do you mean, sir—shout?”

“No, no; tap again.”

“But there arn’t nothin’ to knock on, sir. It’s no good to hit the top, or the floor.”

“But there must be a partition somewhere,” I said.

“Dessay there is, sir; but I can’t tell where it is.”