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An Encyclopedia of the History of Technology part 98

An Encyclopedia of the History of Technology part 98. This one of a kind encyclopedia presents the entire field of technology from rudimentary agricultural tools to communication satellites in this first of its kind reference source. Following an introduction that discusses basic tools, devices, and mechanisms, the chapters are grouped into five parts that provide detailed information on materials, power and engineering, transportation, communication and calculation, and technology and society, revealing how different technologies have together evolved to produce enormous changes in the course of history | PART FIVE TECHNOLOGY AND SOCIETY achievement of modern civil engineering in using new materials in an elegant manner to perform on a huge scale one of the basic public services providing a good water supply. The systematic use of impounding reservoirs to supply water to urban communities in modern times dates from the early nineteenth century when Robert Thom created in 1827 what was then the largest artificial lake in Britain to supply Greenock on the Clyde estuary in Scotland. It retained this distinction until the Vyrnwy and Thirlmere projects at the end of the century see below but by that time extensive water supply projects had been undertaken in many parts of Britain. The first extensive municipal water supply project was that devised by J.F.La Trobe Bateman for Manchester between 1851 when the first part became operational and 1877 when the works were complete. These consisted of five major reservoirs on the River Etherow in the Longdendale valley in the Pennines to the east of the city with their associated aqueducts and auxiliary reservoirs. Bateman used earth embankment dams and had great difficulty in making them stable. Techniques of dam construction improved substantially in the second half of the nineteenth century and pioneering work in Europe on the construction of high-wall masonry dams was adopted in Britain by the end of the century in the Manchester Thirlmere extension in the Lake District 1874-1890 the Liverpool Lake Vyrnwy scheme in north Wales 1881-1892 and the complex of reservoirs to supply Birmingham built in the Elan valley in central Wales 1890-1904 . In the Manchester Haweswater project in the Lake District 1923 concrete became an important constructional material. In those places where surface water has not been easily available thirsty towns and cities have exploited the potential of underground sources. Sometimes natural springs could be directed with little difficulty into water supply systems but more normally wells have been sunk