Literary scholar Robert Hauptman calls this “marginal emendation run amok” — it’s a page from Henry James’ 1877 novel The American as James revised it anxiously for a new edition in 1907. He had decided the plot was unconvincing and asked for so many changes that two copies of the book had to be inlaid page by page on larger sheets to give him room to mark all the revisions. On the last page, above, “James has partially or fully crossed out 16 of the 19 lines and rewritten the text for the definitive New York edition in the margins...