|| Environmental epidemiologist Morris chronicles the at times frightening story of our drinking water. He recounts the epidemics that have shaken cities and nations, the scientists who reached into the invisible and emerged with controversial truths that would save millions of lives, and the economic and political forces that opposed these researchers in a ferocious war of ideas. In the gritty world of nineteenth-century England, a physician proved that cholera could be hidden in a drop of water. In the twentieth century, burgeoning cities subdued cholera and typhoid by building massive filtration plants, and bubbling poisonous chlorine gas through their drinking water. However, in the new millennium, waterborne disease is threatening to reemerge, and research has linked chlorine treatment with cancer and stillbirths. Morris dispels notions of fail-safe water systems, revealing some shocking truths: miles of leaking water mains, constantly evolving microorganisms, and the looming threat of bioterrorism.