Thomas Martyn’s nine-sheet map of Cornwall published in 1748 is the second published large-scale map of the county, after that of the very rare Joel Gascoyne of 1699. Thomas Martyn [1695-1751] was born in Gwennap, near Redruth, Cornwall, in the middle of a mining community. He became a surveyor working on various estates and over a period of 15 years traversed all the county of Cornwall. Immediately after the publication of the large map a reduced, although still large folio map, of the whole was published 16 February 1748/49. This translates in the Gregorian calendar to February 1749. Britain did not adopt the calendar until 2 September 1752; the following day was the 14 September! It is drawn at the scale of one third of an inch to the mile.

The map is extremely ornate and bears an inset map of the Scilly Islands set in the same scale. A note above refers to the placement of it since if it were to be shown correctly the map would be too long. The key shows that some of the symbols are lost from the nine-sheet map as might be expected. Quixley notes ‘the 1749 version is a better balanced, de-cluttered and more pleasing map – more so for being of a more manageable size

It has been noted that many villages only appear on this reduction and are not found on the larger map so this is no mere simplified reduction. It is dedicated to Jonathan Rashleigh of Menabilly, the Member of Parliament for Fowey. An ornate compass rose finishes the map off nicely. Martyn appears not to have married and died on Christmas day 1751 in Ashburton, Devon, whilst working on a survey of the county. The two maps were next issued in 1784 by William Faden and it is this issue which is usually found on the market. Indeed, both of the maps in their first edition are very rare. Only one of the larger has been noted on the market in the last few decades. Provenance: private collection. Palmer (1963) no. 23; Quixley (1966) 32; Quixley (2018) 40; Rodger (1972) 58; Tooley ‘Large Scale – Cornwall’ in ‘Map Collector’ 21 Co 2.