That correspondence was one of the details he had forgotten.

He also stared at Stanistreet, who looked horribly ill.

Then he took up Molly's note and examined it without reading a word.

It was crumpled, dirty, almost illegible, as if Louis had thrust it violently into his pocket, and carried it about with him for weeks.
"If you really don't know what it means," said Stanistreet, "I'll tell you.

It means that your wife had only one idea in her head.