The Signal Camp of Instruction
On Aug. 29, 1861 Maj Myer, an aide to Gen. George B. McClellan, commander of the newly-formed Army of the Potomad, appointed Lt. Samuel T. Cushing to “put the signal party in Camp of Instruction at Red Hill, Georgetown.” Cushing was completely in control.
All officers and soldiers attached to the camp were required to remain in camp, with passes given only in the most urgent cases. They had a rigid schedule for drills and practice, and regular inspections of arms and tents took place regularly.
The order under which the details for signal service were made prescribed that the officers should be "intelligent men of good education, possessing good eyesight, and persons in whom the regimental commanders have especial confidence, the privates to be selected on account of their intelligence, and to be able to read and write."
from Wikipedia