Surveyor and marine cartographer. Born in Orkney, Mackenzie became a school-master in there. Determined to make good charts around these northern islands, which would prevent the heavy loss of life in what were treacherous waters, he set out to undertake a detailed survey of both land and sea from 1742. He published the results of his survey as a fine chart in 1748. To undertake this work he developed new techniques which are described in his Treatise on Maritime Surveying (1774). He was later commissioned by the Admiralty to survey the west coast of Scotland and the north coast of Ireland.