In 1875 he joined the GEOLOGICAL SURVEY OF CANADA. His survey of BC strongly influenced government decisions on the proposed route of the CANADIAN PACIFIC RY. A charter ROYAL SOCIETY OF CANADA member (1882), Dawson by 1883 was assistant director of the GSC. In 1887 he surveyed the Alaska boundary at the Yukon River and investigated gold discoveries there. In 1892 he became British commissioner on Bering Sea natural resources, and in 1896, a member of the Ethnological Survey of Canada. He was also GSC director 1895-1901.
Dawson's brilliance in systematic mapping provided a sound basis for understanding the geology and mineral resources of much of northern and western Canada, and offered reliable guidance to mining, ranching, agricultural and lumbering industries. He also encouraged investigation and development of western coal and petroleum resources. The first comprehensive work on Canada's physiography, Descriptive Sketch of the Physical Geography and Geology of the Dominion of Canada, was published by Dawson and A.R.C. Selwyn (1884).
Author SUZANNE ZELLER