“You mean that this note, though it was written by Prinsep, was not written with reference to the particular occasion we are concerned with.”

“Precisely. Now, I suppose there is no hope of our finding the missing part of that memorandum slip; but I am convinced that is what happened.”

The inspector made a sudden exclamation. “Good Lord! what a fool I have been,” he said.

“How do you mean?” said the superintendent sharply.

“Why, I actually found what must have been the missing part of the slip when I was searching Prinsep’s room. I thought nothing of it at the time.”

“You have it now?”

The inspector shook his head ruefully. “No,” he said, “it has gone west. When I searched the room, I naturally looked in the grate. There had been a fire, and on the hearth was a half-burnt scrap of paper.”

“What was on it?”

“Nothing but the name of a day at the head—Monday, it was—and one word. The rest was burnt. It had evidently fallen out of the grate.”

“The word was?”