“How do you do, Lord Cantlemere? It is chilly for the time of year, but rather warm indoors. May I take your overcoat?”

“No, I thank you; I will not take it off.”

Holmes laid his hand insistently upon the sleeve.

“Pray allow me! My friend Dr. Watson would assure you that these changes of temperature are most insidious.”

His Lordship shook himself free with some impatience.

“I am quite comfortable, sir. I have no need to stay. I have simply looked in to know how your self-appointed task was progressing.”

“It is difficult - very difficult.”

“I feared that you would find it so.”

There was a distinct sneer in the old courtier’s words and manner.

“Every man finds his limitations, Mr. Holmes, but at least it cures us of the weakness of self-satisfaction.”

“Yes, sir, I have been much perplexed.”

“No doubt.”

“Especially upon one point. Possibly you could help me upon it?”

“You apply for my advice rather late in the day. I thought that you had your own all-sufficient methods. Still, I am ready to help you.”

“You see, Lord Cantlemere, we can no doubt frame a case against the actual thieves.”

“When you have caught them.”

“Exactly. But the question is - how shall we proceed against the receiver?”

“Is this not rather premature?”

“It is as well to have our plans ready. Now, what would you regard as final evidence against the receiver?”

“The actual possession of the stone.”

“You would arrest him upon that?”

“Most undoubtedly.”

Holmes seldom laughed, but he got as near it as his old friend Watson could remember.

“In that case, my dear sir, I shall be under the painful necessity of advising your arrest.”

Lord Cantlemere was very angry. Some of the ancient fires flickered up into his sallow cheeks.

“You take a great liberty, Mr. Holmes. In fifty years of official life I cannot recall such a case. I am a busy man, sir, engaged upon important affairs, and I have no time or taste for foolish jokes. I may tell you frankly, sir, that I have never been a believer in your powers, and that I have always been of the opinion that the matter was far safer in the hands of the regular police force. Your conduct confirms all my conclusions. I have the honour, sir, to wish you good-evening.”

Holmes had swiftly changed his position and was between the peer and the door.

“One moment, sir,” said he. “To actually go off with the Mazarin stone would be a more serious offence than to be found in temporary possession of it.”

“Sir, this is intolerable! Let me pass.”

“Put your hand in the right-hand pocket of your overcoat.”

“What do you mean, sir?”

“Come - come, do what I ask.”

An instant later the amazed peer was standing, blinking and stammering, with the great yellow stone on his shaking palm.

“What! What! How is this, Mr. Holmes?”

“Too bad, Lord Cantlemere, too bad!” cried Holmes. “My old friend here will tell you that I have an impish habit of practical joking. Also that I can never resist a dramatic situation. I took the liberty - the very great liberty, I admit - of putting the stone into your pocket at the beginning of our interview.”

The old peer stared from the stone to the smiling face before him.

“Sir, I am bewildered. But - yes - it is indeed the Mazarin stone. We are greatly your debtors, Mr. Holmes. Your sense of humour may, as you admit, be somewhat perverted, and its exhibition remarkably untimely, but at least I withdraw any reflection I have made upon your amazing professional powers. But how- -”