This book, "Train operation by signal indication. I. The two principal methods of directing train movements.II. Directing train movements by signal indication. 2", by Henry Muhlenberg Sperry, is a replication of a book originally published before 1920. It has been restored by human beings, page by page, so that you may enjoy it in a form as close to the original as possible. This book was created using print-on-demand technology. Thank you for supporting classic literature.