About the year 1600 the British government first formed a particular school for the purpose of instructing officers in the art of surveying ground in connection with that part of tactics which relates to the choice of routes and of advantageous positions for troops. These officers were independent of the master-general of the ordnance, and served under the orders of the quartermaster-general or adjutant general ; they were called staff-officers, and were selected from the cavalry or infantry after having done duty with a regiment at least four years. They were first employed in Egypt, where they rendered considerable service ; and the school was afterwards united to the Royal Military/College, which had been then recently instituted for the instruction of cadets who were to serve in the cavalry or the infantry of the line. At that institution a limited number of officers, under tho name of the senior department, continuo to be instructed in the duties of the staff, and in the sciences connected with the military art. All officers aro now obliged to pass an examination before they can be employed on the staff of the army, and they may either enter the Staff College at Sandhurst by a competitive examination, and remain there for two years, or may qualify for the staff by passing the same examination as is required of the officers at Sandhurst at the end of their course of study.
During the war in Spain, from 1808 to 1813, the staff-officers were constantly employed, previously to a march or a retreat, in surveying the country at least ono day's journey in front of the army. After the death of the Duke of York, the staff corps ceased to be kept up, and for several years it was reduced to a single company, which was charged with the duty of repairing the military canal at Hythe. Thin
company was afterwards incorporated with the corps of sappers and miners.
The duties of officers belonging to the quartermaster-general's staff, though in certain respects similar, are different from those of the military engineers ; the latter are employed in the construction of permanent fortifications, batteries, and field-works ; while the former survey ground in order to discover roads, or sites for military positions, for fields of battle, or quarters for the troops. The education of a staff-officer is such as may qualify him for appreciating the military character of ground : for this purpose hs learns to trace the directions of roads and the courses of rivers or streams ; and in mountainous countries to distinguish the principal chains from their ramifications, to examine the entrances of gorges, and to determine the heights of eminences or the depths of ravines. He has, besides, to acquire a facility in determining or estimating the resources of a district with respect to the means it affords of supplying provisions or quarters for the troops. [RECONNAISSANCE.] The staff-officer ought also to know how to correct the illusions to which the eye is subject in examining ground, from the different states of the air, and the number and nature of the objects which may inter vene between himself and those whose positions are required. He ought to be able to estimate the number of men whom a visible tract of ground can contain, and to form a judgment concerning the dispositions and stratagems which it may permit an army to put in practice.