I went on thinking.

"No," I said to myself, "I'm on the wrong tack." So I began again:—

"Some Yorkshire Pot-Holes.

"Lecture delivered before the Blanktown Literary and Philosophical Society, Tuesday, December 8th.

"My Lord Mayor, my Lords——"

"I don't want to interrupt," said Celia coming in suddenly, "but—oh, what's a pot-hole?"

"A curious underground cavern sometimes found in the North."

"Aren't caverns always underground? But you're busy. Will you be in for lunch?"

"I shall be writing my lecture all day," I said busily.

At lunch I decided to have a little financial talk with Celia.