A catechism on the combustion of coal and the prevention of smoke a practical treatise This book, "A catechism on the combustion of coal and the prevention of smoke a practical treatise", by William M. Barr, is a replication of a book originally published before 1900. 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.