A third and successful form of signaling was by the motion of flags. During our Civil War the army made much use of military signals. The system was devised by Major Myer and was continued through the war, not only in the army but on naval vessels. When the stations were less than five miles apart signaling was considered to be at very short range. Messages have been sent ten miles by means of a pocket handkerchief attached to a twelve-foot rod. With the regular flags and staffs used by the signal corps during the war, signals were often read twenty-five miles away, and it is said that single words have been read at a distance of forty miles.
In the early spring of 1863 General Peck was in command of the Union forces at Suffolk, Virginia. He had under him about ten thousand men and had thoroughly fortified the place by a connected system of forts, redoubts, and breast-works. His outmost signal station was placed on an elevated plateau across the Nansemond River. This station was made by sawing off the top of a tall pine tree and placing thereon a small platform surrounded by a railing. The signal officer would tie his horse at the foot of the tree and mount to the platform by a rope ladder.
Early one morning in March, this signal officer suddenly observed the head of a column of troops emerging from the woods in the rear. This was the advance guard of two Confederate corps under General Longstreet. Instantly he caught up his signal flag and as quickly as possible signaled to the town the approach of the enemy. Picking up his signal book he hurried down the ladder, mounted his horse and galloped away. Before he could reach his saddle, however, the Confederates were within rifle range and fired at him. They did not succeed in hitting him and he escaped safely to his friends.
The signal had been seen and was quickly repeated to all parts of the fortified town. The drums instantly beat the long roll and, within five minutes from the time his signal was given, and before General Longstreet could swing out his light battery and open fire, the entire Federal force was under arms and the artillery in the nearest battery had opened a raking fire. The briskness of this fire from the Federal battery soon obliged Longstreet to withdraw his forces to the cover of the woods. Had it not been for the promptness of the signal officer it is possible that the town might have been captured.