Les Cotillions Celebres (in the original French)

Classic French mystery novel, in the original French. The sequel to this book is Les Cotillions Celebres Deuxieme Serie. According to Wikipedia: "Emile Gaboriau (November 9, 1832 - September 28, 1873), was a French writer, novelist, and journalist, and a pioneer of modern detective fiction." One of Robert Louis Stevenson's favorite authors.