Crossover Cover: Sherlock Holmes vs. Jack the Ripper

This book is an adaptation of Jack the Ripper, an 1889 stage play by Gaston Marot and Louis Pericot. Nick Carter appears, and the Gentlemen of the Night (from Paul Féval’s Les Mystères de Londres) are mentioned. There are many pastiches dealing with Holmes battling the Ripper, many of which have their own takes on the Ripper's true identity; Win already included one such book in Volume One, Ellery Queen's A Study in Terror, so I've placed this book in the AU addendum.