"Everything, I say. Think. This was written on the day Cathcart died. Now who in the house would be likely to write these words, 'perceras le coeur ... je suis fou de douleur'? Take everybody. I know it isn't Jerry's fist, and he wouldn't use those expressions. Colonel or Mrs. Marchbanks? Not Pygmalion likely! Freddy? Couldn't write passionate letters in French to save his life."
"No, of course not. It would have to be either Cathcart or—Lady Mary."
"Rot! It couldn't be Mary."
"Why not?"
"Not unless she changed her sex, you know."
"Of course not. It would have to be 'je suis folle.' Then Cathcart—"
"Of course. He lived in France all his life. Consider his bank-book. Consider—"
"Lord! Wimsey, we've been blind."
"Yes."
"And listen! I was going to tell you. The Sûreté write me that they've traced one of Cathcart's bank-notes."