Letters on the Physical History of the Earth, Addressed to Professor Blumenbach. Containing This book, "Letters on the Physical History of the Earth, Addressed to Professor Blumenbach", by Jean André Luc, is a replication of a book originally published before 1727. 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.