With water making up around 70 per cent of the earth's surface and 50 to 65 per cent of the human body, it is only fair to see ourselves as just a little waterlogged. Water is essential to human life and an important component of human history. Humans have generally settled near convenient sources of water and most of the great ancient civilizations depended on a particular source of water. London was no exception, owing its growth and development as England's first city to the rich potential of the Thames as a source of drinking water and power and as a means of communication. During the Industrial Revolution, the growth of commerce placed intolerable pressures on an inadequate road system. A new means of cheap and rapid transportation was needed, marking the beginning of the great age of canals. In the next great advance - steam trains - water was again to play an essential part. Water has brought disaster and disease, such as the nineteenth century cholera epidemic yet conversely spas and sea-bathing show the health-giving side of water. It is surprising how little attention water receives in historical accounts. Stephen Halliday's new book explores the beneficial and harmful ef