Murdoch Mackenzie (1712-97/99) was a chartmaker to the Admiralty. In 1750 he published an atlas of the Orkney and Lewis Islands. This attracted the attention of the Admiralty who commissioned him to survey Ireland and the west coast of Britain the result of which was published in 1776 as ‘A Maritim[sic] Survey of Ireland and the West of Great Britain’ in two volumes. Mackenzie was the first to survey British waters using a measured base line. The first chart in the second volume covering the west coast of Britain is this fine work of the St. George’s and Bristol Channels. It extends along the coastline from Bristol to New Key in Cornwall, and northwards to Caernarvon Shire. The south coast of Wexford county in Ireland is also shown. The finely engraved title cartouche is the work of G. Terry. Evans ‘Marine Plans and Charts of Wales’ in Map Collectors’ Circle no. 54 no. 110; NMM 388; Robinson ‘Murdoch Mackenzie and his Orcades Sea Atlas’ in the Map Collector no. 16 pp. 24-7; Shirley BL Atlases M.Mac 2a vol. 2 no. 1.