"Your desk," I said, "which not unlikely contains private writings and confessions."
"It does," he replied, tapping on the desk with his knuckles. "You little dream of the treasures, the strange secrets, herein contained. You would have this as a hostage?"
"I would."
"It shall be yours, on the understanding that if I claim it from you within three months after the mystery of the murder of Lizzie Melladew is cleared up, you will deliver it to me again intact, with its contents unread."
"I promise faithfully," I said.
"I must trouble you," he said; and he suddenly placed his hand upon my forehead, and stood over me. "Yes," he said, resuming his seat, "the promise is faithfully made. You will keep it."
He locked the desk, and pushed it across the table to me, putting the key in his pocket.
"And now, your word of truth and honour," I said.
"Give me your hand. On my truth and honour I pledge myself to you. Moreover, if it will ease your mind of an absurd suspicion, I declare, on my truth and honour, that I have had nothing whatever to do with this murder."
His words carried conviction with them.