"He was trying to get possession of the letters," I said.
"Oh, so it was that!" and my companion nodded. "And in trying to get those letters, he was killed?"
"Yes, but what none of us understands, M. Armand, is how he was killed. Who or what killed him? How was that poison administered? Can you suggest an explanation?"
He sat for a moment staring thoughtfully out of the window.
"It is a nice problem," he said, "a most interesting one. I will think it over, Mr. Lester. Perhaps I may be able to make a suggestion. I do not know. But, in any event, I shall see you again Wednesday. If it is agreeable to you, we can meet at the house of Mr. Vantine and exchange the cabinets."
"At what time?"
"I do not know with exactness. There may be some delay in getting the cabinet from the ship. Perhaps it would be better if I called for you?"
"Very well," I assented.
"Permit me to express again my apologies that such a mistake should have been made by us. Really, we are most careful; but even we sometimes suffer from careless servants. It desolates me to think that I cannot offer these apologies to Mr. Vantine in person. Till Wednesday, then, Mr. Lester."
"Till Wednesday," I echoed, and watched his erect and perfectly-garbed figure until it vanished through the doorway. A fascinating man, I told myself as I turned back to my desk, and one whom I should like to know more intimately; a man with a hobby for the mysteries of crime, with which I could fully sympathise; and I smiled as I thought of the burning interest with which he had listened to the story of the double tragedy. How naïvely he had confessed his thought that he would have made a great detective—or a great criminal; and here he was only a dealer in curios. Well, I had had the same thought, more than once—and here was I, merely a not-too-successful lawyer. Decidedly, M. Armand and myself had much in common!