Fossil foot-marks in the red sandstone of Pottsville, Pa. This book, "Fossil foot-marks in the red sandstone of Pottsville, Pa", by Isaac Lea, is a replication of a book originally published before 1855. 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.