been considered necessary in our small peace establishment. The functions of the office were not defined, and so far as exercised had been included in the Adjutant-General's Department. The small number of officers in this department, and the necessity for their employment in other duties, have obliged commanding generals during this war to resort to other branches of the service to furnish suitable chiefs of staff..
On the 4th of September, 1861, I appointed Colonel R. B. Marcy, of the Inspector-General's Department, chief of staff, and he entered upon service immediately, discharging the various and important duties with great fidelity, industry, and ability from this period until I was removed from command at Rectortown. Many improvements have been made during the war in our system of staff administration, but much remains to be done.
Our own experience and that of other armies agree in determining the necessity for an efficient and able staff. To obtain this, our staff establishment should be based on correct principles, and extended to be adequate to the necessities of the service, and should include a system of staff and line education.
The affairs of the Adjutant-General's Department, while I commanded the Army of the Potomac, were conducted by Brigadier General S. Williams, assisted by Lieutenant Colonel James A. Hardie, aide-de-camp. Their management of the department during the organization of the Army in the fall and winter of 1861 and during its subsequent operations in the field, was excellent. They were during the entire period assisted by Captain Richard B. Irwin, aide-de-camp, and during the organization of the Army by the following-named officers: Capts. Joseph Kirkland, Arthur McClellan, M. T. McMahon, William P. Mason, and William F. Biddle, aides-de-camp.
My personal staff, when we embarked for the Peninsula, consisted of Colonel Thomas M. Key, additional aide-de-camp; Colonel E. H. Wright, additional aide-de-camp and major Sixth U. S. Cavalry; Colonel T. T. Gantt, additional aide-de-camp; Colonel J. J. Astor, jr., volunteer aide-de-camp; Lieutenant Colonel A. V. Colburn, additional aide-de-camp, and captain Adjutant-General's Department; Lieutenant Colonel N. B. Sweitzer, additional aide-de-camp, and captain First U. S. Cavalry; Lieutenant Colonel Edward McK. Hudson, additional aide-de-camp, and captain Fourteenth U. S. Infantry; Lieutenant Colonel Paul Von Radowitz, additional aide-de-camp; Major H. Von Hammerstein, additional aide-de-camp; Major W. W. Russell, U. S. Marine Corps; Major F. LeCompte, of the Swiss Army, volunteer aide-de-camp; Capts. George A. Custer, Joseph Kirkland, Arthur McClellan, L. P. D'Orleans, R. D'Orleans, M. T. McMahon, William P. Mason, jr., William F. Biddle, and E. A. Raymond, additional ades-de-camp.
To this number I am tempted to add the Prince de Joinville, who constantly accompanied me through the trying campaign of the Peninsula, and frequently rendered important services. Of these officers Captain McMahon was assigned to the personal staff of Brigadier-General Franklin, and Captains Kirkland and Mason to that of Brigadier General F. J. Porter during the siege of Yorktown. They remained subsequently with those general officers. Major LeCompte left the Army during the siege of Yorktown; Colonels Gantt and Astor, Major Russell, Capts. L. P. D'Orleans, R. D'Orleans, and Raymond, at the close of the Peninsular campaign. Before its termination Capts. W. S. Abert and Charles R. Lowell, of the Sixth U. S. Cavalry, joined my staff as aides-de-camp, and remained with me until I was relieved from the command of the Army of the Potomac. All of these officers served me