Excerpt from Instructions for Officers and Non-Commissioned Officers on Outpost and Patrol Duty, and Troops in Campaign
Grand Guards will be sent out by all brigades in camp when in the face of the enemy, for safety; when in a friendly' country, for instruction. All Colonels and others in authority will see that their commands are instructed in these duties.
The U.S. Department of War was the United States Cabinet department originally responsible for the operation and maintenance of the United States Army, also bearing responsibility for naval affairs until the establishment of the Navy Department in 1798, and for most land-based air forces until the creation of the Department of the Air Force on September 18, 1947.