Royal Observer Corps
In 1929 the control of the Observer Corps passed from the county police forces to the Air Ministry, although Chief Constables retained responsibility for personnel and recruitment matters. 1 March 1929 saw the establishment of the new "Headquarters of the Observer Corps" at Hillingdon House, RAF Uxbridge in the west of London, and Air Commodore Edward A D Masterman CB CMG CBE AFC RAF (Rtd) was appointed as the first commandant of the Observer Corps. "Air Cdre" Masterman held this appointment until his retirement on 1 March 1936, and was succeeded by Air Commodore Alfred Warrington-Morris CG CMG OBE AFC RAF (Rtd), who would lead the Observer Corps through the critical period during the Second World War which saw the RAF emerge bruised but victorious following the Battle of Britain of 1940.
Ordnance Survey
Roy later had an illustrious career in the Royal Engineers (RE), rising to the rank of General, and he was largely responsible for the British share of the work in determining the relative positions of the French and British royal observatories. This work was the starting point of the Principal Triangulation of Great Britain (1783–1853), and led to the creation of the Ordnance Survey itself. Roy's technical skills and leadership set the high standard for which Ordnance Survey became known. Work was begun in earnest in 1790 under Roy's supervision, when the Board of Ordnance (a predecessor of part of the modern Ministry of Defence) began a national military survey starting with the south coast of England. Roy's birthplace near Carluke in South Lanarkshire is today marked by a memorial in the form of a large OS trig point.