1860: Albert J. Myer, developer of flag "wig-wag" code appointed Signal Officer.
Myer designed the flag signaling system when working in American Indian territory in the 1850s. He noticed Native Americans communicating across long distances by waving staffs to each other. Adding a flag to the staff and then a square on the flag so that it could be better seen, the system came to be accepted as the line of site communication system used extensively during the Civil War by Union and Confederate forces. Ironically, it was first used at the Battle of First Manassas by Edward Porter Alexander, who was Myer's aide who helped develop the system before the war. During the battle, Alexander positioned himself at a signal station on what is now known as Signal Hill. When he saw a flash of light reflecting from a brass cannon, he saw the impending movements of the enemy. Federal troops were about to flank Col. Nathan G. Evans of South Carolina. Alexander grabbed a signal flag and sent a message to Evans, "Look to your left, you are turned," thus indicating that the colonel's regiment was going to be flanked on his left. After receiving this message, Evans took the necessary movement to defend against the Union's flanking attack.
See links at the end of this page to NCMF Acquisitions related to Civil War signaling, NCM Civil War Signal Exhibit, and other related links.
About Myer - from Wikipedia: Myer engaged in private medical practice in Florida and then sought a commission as a U.S. Army assistant surgeon (lieutenant), entering service September 18, 1854, posted at Fort Duncan, Texas, and Fort Davis, Jeff Davis County, Texas. His major interest of the time, besides medicine, was to devise a system of signaling across long distances, using simple codes and lightweight materials. This system of codes using a single signal flag (or a lantern or kerosene torch at night), known as wig-wag signaling or aerial telegraphy, would be adopted and used by both sides in the Civil War and afterward.