A scarce folding map of Cornwall

A large and detailed map of Cornwall, reduced from Martyn's 9-sheet, inch to the mile, survey of c.1748. It has decorative cartouches for the title, dedication and scale and an inset map of the Scillys on a banner. A large compass rose and three illustrations of ancient inscriptions complete the design. Martyn (1695-1751) was a miner and mathematics teacher, surveyed estates before embarking on his survey of the whole county. Although his map was not the first large-scale map of the county (Joel Gascoigne had issued one in 1700), Martyn's was the most thorough. Coloured examples of his nine-sheet map sold for three guineas, a considerable amount at the time, but the publication was a great success, leading to this reduction and, seventy years after first publication, a 95-page index,