THE ARMY OFFICER'S POCKET COMPANION; PRINCIPALLY DESIGNED FOR STAFF OFFICERS IN THE FIELD. PARTLY TRANSLATED FROM THE FRENCH OF M. DE ROUVRE, LIEUTEN- ENGLISH AUTHORITIES. BY WILLIAM P. CRAIGHILL, ENGINEERS, FIRST-LIEUTENANT U. S. CORPS OF ENGINEERS, ASSISTANT PROFESSOR OF ENGINEERING AT THE U. S. MILITARY ACADEMY. NEW YORK: D. VAN NOSTRAND, 192 BROADWAY. 1862. U130 07 Entered according to Act of Congress, in the year 1861, In the Clerk's Office of the District Court of the United States, for the Southern District of New York. 0. A. ALVORD, STEREOTYPER AND PRINTER. PREFACE. THIS book in its beginning was intended to be a translation from the Aide-mémoire of the French Corps d'État-Major, prepared by Colonel de Rouvre. There is no such corps in the army of the United States. The duties of the Corps d'État-Major, or Staff-Corps, are very extensive and important, as will be perceived from an examination into their details. An officer of this corps, to be fitted for his position, should be capable, among other things, of filling the place of almost any other officer of the army. It readily appears, therefore, that an Aide-mémoire for such officers is an Aide-mémoire for the whole army, but especially for staff officers. The matter may be divided into three classes; 1st, those portions applicable only to the French army, which are specially stated as so belonging, being retained here because they furnish valuable and interesting information to the officers of the army of the Union, and give indications of what might well be added to our system; (this is a small part of the work.) 2d, those portions ap |