Mrs. Markham was called away on some household errands then, and Fessenden remained alone in the library, trying to think of some clue that would point to someone other than Carleton.

“I’m sure that man is not a murderer,” he declared to himself. “Carleton is peculiar, but he has a loyal, honest heart. And yet, if not, who can have done the deed? I can’t seem to believe it really was either the Dupuy woman or the Burt girl. And I know it wasn’t Schuyler! There must have been some motive of which I know nothing. And perhaps I also know nothing of the murderer. It need not necessarily have been one of these people we have already questioned.” His thoughts strayed to the under-servants of the house, to common burglars, or to some powerful unknown villain. But always the thought returned that no one could have entered and left the house unobserved within that fatal hour.

And then, to his intense satisfaction, Kitty French came into the room.