Roy Military Survey of Scotland, 1747-1755
Background to the Survey and William Roy
The most obvious impetus to the Roy Military Survey was the Jacobite Rebellion of 1745-1746, when the Hanoverian military commanders in Scotland found themselves 'greatly embarrassed for want of a proper Survey of the Country' (John Watson, 1770, quoted in the Royal Scottish Geographical Society's, Early Maps of Scotland to 1850, 1973, p.105). Specifically, Colonel David Watson (then Deputy Quartermaster-General in the Board of Ordnance, a body with responsibility for military infrastructure and mapping) promoted the idea to William Augustus, Duke of Cumberland. Soon after his victory at Culloden, Cumberland successfully petitioned King George II (his father) for the Military Survey of Scotland and in 1747 Watson was instructed to begin work. He in turn delegated the primary practical responsibility to his Assistant Quartermaster, William Roy.
The broader principles or requirements behind the Roy Military map had several parallels in Europe (particularly France, Brandenburg-Prussia, and the Low Countries) as well as North America and Canada. During the 18th century, military commanders increasingly came to appreciate and use topographic mapping for a range of purposes, and partly due to the shortcomings of private or civilian map-making, a growing cadre of military engineers and draughtsmen were required to create new maps.
Mapping context and purpose
By the 1740s, the most detailed regional maps available for Scotland were those based on the surveys of John Adair in the 1680s, with very incomplete coverage of the country at variable scales. More recent military maps at standard scales, such as the manuscript map by Clement Lempriere (ca 1730), or the printed map of John Elphinstone (1745) lacked the detail required for moving troops and planning campaigns. The Roy Map was part of a broader strategy to open up the Highlands, in parallel with the construction of an extensive road network, connecting newly built forts and repaired military strongholds.
More generally, the cartographic imperatives behind the Roy map can be seen to reflect growing Enlightenment aspirations for greater geometrical accuracy and standardisation, as well as a desire to discover empirical truth, and to control and order geographical space through reconnaissance and survey. These values embodied in the Roy map, can also be seen in those maps it particularly influenced, 'such as the Survey of Canada and St Lawrence by George Murray (1760-61), the east coast of North America by Samuel Holland (1764-65), of Bengal by James Rennell (1765-77), and of Ireland by Charles Vallencey (1778-90)' (O' Donoghue, 1977, p.4)
Born at Miltonhead, near Carluke, William Roy (1726-1790) was the son of an estate factor and attended the grammar school at Lanark. Little is known of how he acquired his mapping expertise, though some historians have speculated that he worked for the Post Office in Edinburgh as a surveyor of roads, as well as for the Board of Ordnance as a draughtsman. The Board of Ordnance was critically short of engineers in the late 1740s - only four were available in Scotland in 1748 - and Roy probably undertook the initial work on the Survey around Fort Augustus and further afield single-handedly.
From 1748 Roy was assisted by six surveying parties, with six men within each survey party; the Highlands were largely complete by 1752, while southern Scotland (south of the Forth-Clyde line) was completed by 1755.
We can see the handiwork of Roy, who was widely praised as a draughtsman, in some of the content of the map itself - for example, the topographic detail and lettering on the fair copy, and parts of the map along the Border with England. Perhaps as a logical extension of his interest in military conquest, Roy took a particular personal enthusiasm for mapping Roman military antiquities, including a detailed survey of the Antonine Wall in 1755.
On 23 December 1755, William Roy was appointed a practitioner-engineer, thus gaining military rank for the first time, at the same time as military priorities elsewhere (with the outbreak of the Seven Years War) took him away from Scotland. Roy drafted maps of southern England in 1756 (due to concern over a French invasion) as well as a battle plan of Minden (1759). He reached the rank of Major-General by 1781, and regularly promoted the idea of a complete triangulation of Britain (incorporating the [Roy's Military Survey of Scotland) as a basis for better mapping. He led the English side of the geodetic connection of London and Paris by triangulation in the 1780s, promoted by Cassini de Thury of the Paris Observatory.
Finally, through Roy's efforts and his promotion of the construction of a new three-foot theodolite by Jesse Ramsden, the accurate measurement of a base line on Hounslow Heath laid the foundation of the Trigonometrical Survey of Great Britain in 1791. This was later to become the Ordnance Survey.
View the Roy map: