"It is a loss open to explanation," mildly resumed the aged detective. "It is also one which the police deems important. We shall have to search for that connecting slip of paper unless, as I sincerely hope, someone here present can produce it."

"Search!" a commanding voice broke in—that of Leighton. "We know nothing about it."

"It is a pity," rejoined the old man, with a mildness unusual in one of his class. "Such a measure should not be necessary. Someone here ought to be able to direct us where to find this missing portion of a letter interrupted by so stern a fact as the writer's death."

Still no answer.

"Had there been a fire in the room—but there was no fire. Or had Mr. Gillespie left the room——"

"Speak out!" the stern tones again enjoined. "You think some of us took it?"

"I do not say so," was the conciliatory reply. "But this scrap must be found. Its remarkable disappearance shows that it has more or less bearing on the mystery of your father's death."

"Then we must entreat you to use your power and find it if you can." It was still Leighton who was speaking. "George, Alfred, let us accept the situation with good grace; we will gain nothing by antagonising the police."

Two muffled oaths answered him; their natures were more passionate than his, or possibly less under control. But they offered no objections, and the next minute the old detective appeared in the hall.

One look passed between him and the young man loitering at my side. Then the latter turned to me: