“I have long known, sir, how high is your sense of public duty,” said he. “I am convinced that in the case of a secret of this importance it would rise superior to the most intimate domestic ties.”

The European Secretary bowed.

“You do me no more than justice, sir. Until this morning I have never breathed one word to my wife upon this matter.”

“Could she have guessed?”

“No, Mr. Holmes, she could not have guessed⁠—nor could anyone have guessed.”

“Have you lost any documents before?”

“No, sir.”

“Who is there in England who did know of the existence of this letter?”