The filtration of public water-supplies: Third edition, revised and enlarged.

"The Filtration of Public Water-Supplies" by Allen Hazen is a scientific publication written in the early 20th century. The book discusses the critical importance of filtration systems used to purify water supplies, specifically focusing on practices in the United States compared to those in densely populated European countries. It aims to stimulate interest in improving water quality and outlines established methods and necessary conditions for effective water filtration. At the start of the book, Hazen highlights the historical development of water filtration, acknowledging earlier efforts in the United States and contrasting them with successful European practices. He underscores the detrimental effects of using unfiltered water, referencing grave public health issues like cholera outbreaks. The introduction sets the stage for discussing the fundamental principles of filtration, the evolution of methods, and emphasizes the role of proper filtration systems in ensuring the health of urban populations. This opening portion establishes a foundation for a detailed examination of filtration technologies and their significance in public health and engineering, promising a comprehensive resource for those interested in environmental science and engineering practices.