"At the beginning of the wars of the Revolution," says this able historian elsewhere, "in the French army the general staff, which is essential for directing the operations of war, had neither instruction nor experience." The several adjutant-generals attached to the army of Italy were so utterly incompetent, that Napoleon became prejudiced against the existing staff-corps, and virtually destroyed it, drawing his staff-officers from the other corps of the army. In his earlier wars, a large portion of staff duties were assigned to the engineers; but in his later campaigns the officers of this corps were particularly required for the sieges carried on in Germany and Spain, and considerable difficulty was encountered in finding suitable officers for staff duty. Some of the defects of the first French staff-corps were remedied in the latter part of Napoleon's career, and in 1818 it was reorganized by Marshal Saint-Cyr, and a special school established for its instruction. Some European nations have established regular staff-corps, from which the vacancies in the general staff are filled; others draw all their staff-officers from the corps of the army. A combination of the two systems is preferred by the best judges. Jomini recommends a regular staff-corps, with special schools for its instruction; but thinks that its officers should be drawn, at least in part, from the other corps of the army: the officers of engineers and artillery he deems, from their instruction, to be peculiarly qualified for staff duty. The policy of holding double rank at the same time in the staff and in the corps of the army, as is done in our service, is pronounced by all competent judges as ruinous to an army, destroying at the same time the character of the staff and injuring the efficiency of the line. The following remarks on the character and duties of general-officers of an army, made at the beginning of the war of 1812, are from the pen of one of the ablest military writers this country has yet produced:-- "Generals have been divided into three classes,--_Theorists_, who by study and reflection have made themselves acquainted with all the rules or maxims of the art they profess; _Martinets_, who have confined their attention merely to the mechanical part of the trade; and _Practical men_, who have no other or better guide than their own experience, in either branch of it. This last description is in all services, excepting our own, the most numerous, but with us gives place to a fourth class, viz., men destitute alike of _theory_ and of _experience_."