First published in 1925 as an extended second edition of a 1915 original and as part of the Cambridge Public Health Series, this book discusses the various forms of sewage treatment, with a particular eye to cost efficiency. Kershaw includes a suggested bibliography at the end of every chapter, and the text is illustrated with diagrams and photographs of machines and buildings related to sewage purification and effective disposal. This book will be of value to anyone with an interest in public health and the history of public health education.