Naturalist, lecturer and clergyman. Born in the Canongate (Edinburgh), Walker read divinity at the University of Edinburgh from the age of sixteen. He was ordained as a Minister in the Church of Scotland, serving the parishes of Glencorse (1758-62), Moffat (1762-83) and finally Colinton (1783 - 1803).
Stimulated by lectures in natural philosophy while at university, he continued to study chemistry and mineralogy under Prof. William Cullen (1710-90). He was also greatly influenced by Henry Home, Lord Kames (1696 - 1782) who appointed Walker to undertake a remarkable survey of the Hebrides and the Highlands in 1764. The report was published as the Economical History of the Hebrides (1808).
Walker became a noted figure of the Scottish Enlightenment and, with the patronage of his influential friends, he was appointed to the Regius Chair of Natural History at the University of Edinburgh in 1779. His lectures covered a diverse range of topics including agriculture, botany, geology, hydrography, meteorology, mineralogy and zoology. His lectures on agriculture are said to have been the first at any English-speaking university.
