Edge books. Sanitation investigation

Describes the history of sewage treatment and discusses wastewater treatment plants, rats that live in sewers, and other related topics.

Explores the history of the toilet from ancient times, and how people dealt with human waste before its invention.

Describes how garbage and trash has been discarded throughout history and what happens to the trash that is put into dumps.

Describes how water is purified before it comes into the home and the effects of unclean water on the body.