Sulphon-phthaleins derived from ortho-sulpho-paratoluic acid This book, "Sulphon-phthaleïns derived from ortho-sulpho-paratoluic acid", by Walter Jones, is a replication of a book originally published before 1891. 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.