“’Londoners are now in such a state of nerves—­if I may use the expression, in such a state of funk—­that every passer-by, however innocent, is looked at with suspicion by his neighbour if his avocation happens to take him abroad between the hours of one and three in the morning.’

“I’d like to gag that ex-Lord Mayor!” concluded Joe Chandler wrathfully.

Just then the lodger’s bell rang.

“Let me go up, my dear,” said Bunting.

His wife still looked pale and shaken by the fright she had had.

“No, no,” she said hastily.  “You stop down here, and talk to Joe.  I’ll look after Mr. Sleuth.  He may be wanting his supper just a bit earlier than usual to-day.”

Slowly, painfully, again feeling as if her legs were made of cotton wool, she dragged herself up to the first floor, knocked at the door, and then went in.

“You did ring, sir?” she said, in her quiet, respectful way.

And Mr. Sleuth looked up.

She thought—­but, as she reminded herself afterwards, it might have been just her idea, and nothing else—­that for the first time the lodger looked frightened—­frightened and cowed.

“I heard a noise downstairs,” he said fretfully, “and I wanted to know what it was all about.  As I told you, Mrs. Bunting, when I first took these rooms, quiet is essential to me.”

“It was just a friend of ours, sir.  I’m sorry you were disturbed.  Would you like the knocker taken off to-morrow?  Bunting’ll be pleased to do it if you don’t like to hear the sound of the knocks.”

“Oh, no, I wouldn’t put you to such trouble as that.”  Mr. Sleuth looked quite relieved.  “Just a friend of yours, was it, Mrs. Bunting?  He made a great deal of noise.”

“Just a young fellow,” she said apologetically.  “The son of one of Bunting’s old friends.  He often comes here, sir; but he never did give such a great big double knock as that before.  I’ll speak to him about it.”

“Oh, no, Mrs. Bunting.  I would really prefer you did nothing of the kind.  It was just a passing annoyance—­nothing more!”

She waited a moment.  How strange that Mr. Sleuth said nothing of the hoarse cries which had made of the road outside a perfect Bedlam every hour or two throughout that day.  But no, Mr. Sleuth made no allusion to what might well have disturbed any quiet gentleman at his reading.

“I thought maybe you’d like to have supper a little earlier to-night, sir?”

“Just when you like, Mrs. Bunting—­just when it’s convenient.  I do not wish to put you out in any way.”

She felt herself dismissed, and going out quietly, closed the door.

As she did so, she heard the front door banging to.  She sighed —­Joe Chandler was really a very noisy young fellow.

CHAPTER XVII

Mrs. Bunting slept well the night following that during which the lodger had been engaged in making his mysterious experiments in her kitchen.  She was so tired, so utterly exhausted, that sleep came to her the moment she laid her head upon her pillow.