Puget Sound Civil War Roundtable

Civil War Education, Remembrance and Preservation

SIGNAL CORPS

The Problems

Inasmuch as the first working telegraph was produced in 1836 and the first coded message was sent in 1844, military communication would seem to have been solved by 1861. But, that is not the case for several important reasons:
1. Distances between signal stations were sometimes quite long;
2. Obstacles such as rivers, valleys and swamps prevented conventional telegraph systems;
3. The need for secrecy precluded the use of standard Morse Code; and
4. Battlefield conditions caused near-rapid movement of combatants.

NAVIGATION
Signaling
Decoding
Equipment

A New Language

In the 1850s, a system of communication for sending messages over long distances was established by Albert J. Myer, M.D. A doctor, Myer’s doctoral thesis was “A New Sign language for Deaf Mutes,” a basis for his later concept of signaling. Using signal flags during the day and torches at night, his system of “wig-wag” signaling or “aerial telegraphy” was adopted by both sides during the Civil War. Myer began testing it on the east coast in 1859.

One of his principal assistants during this testing phase was Edward Porter Alexander, a future Confederate artillery officer who commanded artillery positions on the northern end of Lookout Mountain during the siege of Chattanooga. Able to communicate put to 15 miles during the testing phase, Myer’s system was adopted and first successfully used in New Mexico during the 1860-61 Navajo expedition. With the outbreak of the Civil War, Myer was recalled to Washington and made chief signal officer for the Army.

Civil War Signaling

One of the most notable used of Civil War signaling occurred during the 1863 Chattanooga campaign. The various ridges that surround the city provided an excellent opportunity for the establishment of signal stations to send messages for both the Union and Confederate forces. One of the sites used as a Confederate signal station was on the northern point of Lookout Mountain where Union troop movements through Lookout Valley could easily be watched.

On November 23, with the Battle of Orchard Knob beginning to unfold to the east of Chattanooga, Confederate General Carter Stevenson made his way to the signaling station at the north end of Lookout Mountain where he observed the battle. That evening, Stevenson sent the following message by signal to Generals Braxton Bragg and William j. Hardee:

“I observed closely from the point the movements of enemy until dark. An object seemed to be to attack our attention. All the troops in sight were formed from center to left. Those on their right moved to center. The troops from Raccoon were in line in full sight. if they intended to attack, my opinion is, it will be on our left. Both of their bridges are gone.”

During the siege, Union forces were able to crack the Confederate signal code, giving the Union Army a strategic advantage.

Role of the Signal Corps

With battle came the need for communication. A troop newly arrived to a battle could not know the status of another troop across the field easily. With bullets flying and the enemy in sight, how could one troop talk with another? The answer originally was developed by a New York man by the name of Albert J. Myer. Myer created a system of “talking flags” - flags that with a code of waves created an alphabet and could be seen from far distances allowing two troops o signal to each other with messages. The “talking flags” became known as “signal flags” and the men who knew how to converse with them became known as the Signal Corps. Although a Union man, his idea was so ingenious, it was adopted by the Confederates as well, thanks to another Union soldier turned Confederate, E. P. Alexander, who had trained under Myer.

Corps members were placed in a Signal Camp of introduction and taught to use a “Signal Kit”. Amont that kit were seven flags ranging from 2 foot to 5 foot square. The colors varied from white with a red square in the middle to red with a white square in the middle to the same with whet and black. The choice of flag used was solely for practical purposes. If it was a clear day with a blue sky, the white flag with the red square would be hard to see. Therefore, either the red with white square or the black with white square would be used. If there were a grove of trees behind them, the white with red square flag would be used. If there was much smoke from cannon fire, the black with white square might be used. The size flag was determined according to the distance between troops with the 4 foot flag being the most common.

The signal officer would need to have a good line of sight to the opposing troop. Usually, the flagmen would have found a hilltop, house top or tree top to gain a straight line of sight. Using a telescope and field glasses, he would watch the actions of the flagman across the field and dictate to an waiting corpsman to record and transmit, or will transmit himself.

The flagman begins with a “call for attention”, which is basically a constant waving back and forth of the float location 1 and 2, also known as a “wig-wag”. Then, the code begins. The flag is raised straight up and through a series of waves, left and right, each set of waves creates a letter or abbreviation. When a word is completed, the flag comes down the center and another code meant the end of the message. At night, communication was just as crucial and therefore “talking torches” took the place of signal flags.

There are four signal methods: one, two, three and four element codes. One-element signals were not used too often, and generally for a few commonly used messages. Two-element signals were most adaptable for universal use. Three-element signals allow the alphabet to be represented using three signals for each letter, no more or less. This makes it easy to know when a letter is completed. The four-element signal is very similar to the two-element code, but more fluid.