William Newsham Blair (1841-91) was born in Scotland, and trained there as an engineer and surveyor. He emigrated to Dunedin at the end of 1863 and took employment with the Otago Provincial Survey Department at the beginning of the new year. In 1871, he became District Engineer of Public Works, and in 1878, the year after election as a Member of the Institution of Civil Engineers, was appointed Engineer-in-Charge of Public Works in the South Island. In 1884, Blair moved to Wellington as Assistant Engineer-in-Chief. In 1890, he became Engineer-in-Chief and Under Secretary for Public Works (Furkert 1953: 117). During his career as engineer, Blair had many opportunities to travel throughout New Zealand. For example, in the 1870s he travelled widely throughout Otago and Canterbury (including traversing the Southern Alps five times) while on reconnaissance surveys for possible railway routes, and in the 1880s he visited the King Country to report on the proposed North Island Main Trunk. It was no doubt on these and similar journeys that Blair became very much aware of the changes which man was making to the landscape. A few earlier writers had expressed concern about the wholesale clearing of the natural vegetation, but none had noted the scale of man-induced erosion and change. Similarly Blair refused to accept a commonly held theory that rainfall increased if forests were planted, and decreased if the land was denuded. In some ways, Blair may be compared with George Perkins Marsh in the United States. Over two decades earlier Marsh had already recognised that man was a potent force in changing his environment. It is interesting to speculate if indeed Blair had found his inspiration in the writings of this American naturalist. Introduction by R.P. Hargreaves