Mr. Priestley abandoned the low, firm voice and substituted a louder edition. “I fear I have some unpleasant news for you,” he roared above the din of the train. Chatty conversation on the Underground is best carried on between a retired fog-horn and a bull from Bashan.

“If it’s your tools,” the girl howled cheerfully, “I——”

“It isn’t my tools,” bellowed Mr. Priestley with a testiness which quite surprised him. “It’s this. I regret that I shall be unable to—er—to break into this house for you.”

“Unable to——?” The girl looked at him with astonishment. “What do you mean?” she shrieked.

At that moment the train considerately slowed down to approach a station, and the interchange of ideas became easier.

“What do you mean?” repeated the girl, in more normal tones.

Mr. Priestley wriggled uneasily. “I—I’ve reformed, you see,” he mumbled.

“You’ve what?”

“Reformed. I—I’m not going to burgle any more.”

“Why ever not?”