Signal Corps in the American Civil War
The Signal Corps in the American Civil War comprised two organizations: the
The Union Signal Corps, although effective on the battlefield, suffered from political disputes in
U.S. Army (Union) Signal Corps
First chief signal officer
The "father" of the U.S. Army Signal Corps was Major
Myer began testing in April 1859 at
On March 29, 1860, the United States House of Representatives approved the Army appropriations bill for fiscal year 1861, which included the following amendment:
For the manufacture or purchase of apparatus and equipment for field signals, $2000; and that there be added to the staff of the Army one signal officer, with the rank, pay, and allowance of a major of cavalry, who shall have charge, under the direction of the Secretary of War, of all signal duty, and all books, papers, and apparatus connected therewith.[3]
The United States Senate eventually approved the appropriations bill, over the objections of Jefferson Davis, now Senator from Mississippi, and President James Buchanan signed it into law on June 21, 1860, the date now celebrated as the birthday of the modern U.S. Army Signal Corps. Myer's appointment as the first signal officer with the rank of major was confirmed by the Senate on June 27.[4] However, the appropriations bill provided for no personnel to work for Myer and the Signal Corps as a formal organization would not be authorized until March 1863.[5]
Immediately before the war, Myer was assigned to the Department of New Mexico to test his signals in the field during a campaign against the
War organization
Upon the outbreak of war, Myer returned to Washington and addressed the problem of having no signal personnel. His only option was to persuade officers to be detailed from other assignments, which was not considered satisfactory by Myer or the officers themselves, who feared loss of promotion opportunities. He submitted draft legislation to Secretary of War
Myer's persistence paid off when President Abraham Lincoln signed a sundry civil appropriations bill on March 3, 1863, which authorized the organization of a Signal Corps during the "present rebellion." It included the position of chief signal officer with the rank of colonel, a lieutenant colonel, two majors, a captain for each corps or military department, and as many lieutenants, not to exceed eight, per corps or department as the president deemed necessary. Each officer was provided one sergeant and six privates. Myer was appointed to the position of chief signal officer and the rank of colonel by Secretary Stanton on April 29, but his appointment could not be immediately confirmed by the Senate, which was in recess.[8]
Although Myer interpreted his appointment to include control over electromagnetic telegraphy, a rival organization emerged. The
Nicodemus inherited an organization that had grown to approximately 200 officers and 1000 enlisted men. He also ran afoul of Secretary Stanton when the 1864 annual report for the Signal Corps was published because it revealed that the corps was able to read the enemy's signals. Stanton rightfully believed this to be a breach of security and he dismissed Nicodemus from the Army in December 1864. The final chief signal officer during the war was Colonel
The Signal Corps completed its wartime service and was dissolved in August 1865. During its lifetime, 146 officers were commissioned in the corps or were offered commissions. There were 297 acting signal officers appointed, although some were for very brief periods. The total number of enlisted men who served during the war was about 2,500.[11]
Albert Myer was eventually rescued from oblivion. In May 1864, Myer's prewar ally, Edward Canby, selected him to be the signal officer for the Military Division of West Mississippi. Myer served in this position as a major because his confirmation as a colonel had been revoked after his dismissal from Washington. At the end of the Civil War, he was given a brevet promotion to brigadier general. On July 28, 1866, reacting to the influence of Lt. Gen. Ulysses S. Grant and President Andrew Johnson, Congress reorganized the Signal Corps and, with the permanent rank of colonel, Myer again became chief signal officer, as of October 30, 1866. His new duties included control of the telegraph service, resolving the dispute that had removed him from his position.[11]
Confederate Signal Corps
Edward P. Alexander, Myer's assistant in testing the wig-wag signaling system, resigned his U.S. Army commission on May 1, 1861, to join the Confederate Army as a captain of engineers. While organizing and training new recruits to form a Confederate signal service, he was ordered to report to
Although the Confederate Signal Corps would never achieve a distinct branch identity to the extent that the Union version did, the Confederate Congress authorized its establishment as a separate organization, attached to the Adjutant and Inspector General's Department, on April 19, 1862, a year before the U.S. Congress did so. The first chief signal officer was Captain
Signal equipment and techniques
Wig-wag signaling
Wig-wag signaling was performed during daylight with a single flag tied to a hickory staff constructed in four-foot jointed sections. Flags were generally made of cotton, linen, or another lightweight fabric and were issued in the following sizes:[14]
Flag size (feet) | Flag background color | Center color | Center size (inches) |
---|---|---|---|
6 x 6 | white | red | 24 x 24 |
6 x 6 | black | white | 24 x 24 |
4 x 4 | white | red | 16 x 16 |
4 x 4 | black | white | 16 x 16 |
4 x 4 | red | white | 16 x 16 |
2 x 2 | white | red | 8 x 8 |
2 x 2 | red | white | 8 x 8 |
The 4-foot flags with white backgrounds, mounted on 12 foot staffs, were most often used, although 2-foot flags were used when the flagman wanted to avoid enemy attention. Red flags were generally used at sea. For nighttime signaling, torches were copper cylinders, 18 inches long and 1.5 inches in diameter with a cotton wick.[14]
Myer's "General Service Code" for wig-wag signaling, standardized in 1864, was also known as the "four element" code because all of the characters transmitted were composed of from one to four flag motions. (Myer's original method from the 1850s was called a "two element code" because elements were described only in terms of movement from the vertical position.) The flagman took a position facing the station to receive the message and signaled digits "1" through "5" as follows:[15]
- Wave the flag from the vertical position to the ground at the left of the flagman, returning immediately to the vertical position.
- Wave the flag from the vertical position to the ground at the right of the flagman, returning immediately to the vertical position.
- Wave the flag from the ground on the right to the ground on the left of the flagman, returning immediately to the vertical position. The signal "3" always followed a "2" or "4."
- Wave the flag from the ground on the left to the ground on the right of the flagman, returning immediately to the vertical position. The signal "4" always followed a "1" or "3."
- Wave the flag directly in front of the flagman to the ground, returning immediately to the vertical position.
Codes for the alphabet, digits, and some special characters were as follows for the Union Signal Corps:
A - 11 | F - 1114 | K - 1434 | P - 2343 | U - 223 | Z - 1111 | 1 - 14223 | 6 - 23111 |
B - 1423 | G - 1142 | L - 114 | Q - 2342 | V - 2311 | & - 2222 | 2 - 23114 | 7 - 22311 |
C - 234 | H - 231 | M - 2314 | R - 142 | W - 2234 | tion - 2223 | 3 - 11431 | 8 - 22223 |
D - 111 | I - 2 | N - 22 | S - 143 | X - 1431 | ing - 1143 | 4 - 11143 | 9 - 22342 |
E - 23 | J - 2231 | O - 14 | T - 1 | Y - 222 | ed - 1422 | 5 - 11114 | 0 - 11111 |
Waving the flag continuously from left to right was used to attract attention and to indicate that signaling was about to start. Other special sequences of digits were:
5 | End of word |
55 | End of sentence |
555 | End of message |
11, 11, 11, 5 | "I understand" |
11, 11, 11, 555 | "Cease signaling" |
234, 234, 234, 5 | "Repeat" |
143434, 5 | "Error" |
Telegraph train and the Beardslee telegraph
Telegraph trains were introduced by Myer to support telegraphy for mobile operations. The horse-drawn wagons carried the telegraph sets and supplies such as reels of insulated copper wire and iron lances, for stringing temporary field lines, a practice called "flying telegraph lines." Each train consisted of two wagons, equipped with 5 miles of wire and a telegraph instrument. The first model train was constructed by Henry J. Rogers, a telegraphic engineer from New York City who had worked with
For its first use in combat, during the 1862
Ciphers
Since aerial telegraphy was sometimes conducted within the clear sight of the enemy, security was a major problem. The Signal Corps introduced a cipher disc, a simple device that allowed the encryption of text. Two concentric discs were inscribed with letters and their numerical equivalents. The sending and receiving party had to agree on the specific alignment between the two discs, ensuring that both parties had identical alignment. To encipher a message, the signal officer selected an "adjustment letter" on the inner disc and then made this letter correspond with a preselected numerical code or "key number" on the outer disc. The signal officer would typically give the key numbers to the flagmen without revealing the plain text version of the message. Although this method of encryption was primitive by modern standards, there is no record that the Confederates ever deciphered a Union message that had been processed in this manner. A more complex system in which four concentric discs were used was invented by Sergeant Francis M. Metcalf and modified by Captain Lemuel B. Norton, but it did not receive widespread adoption.[17]
Signal contributions to battles and campaigns
First Bull Run
At the First Battle of Bull Run, Confederate Capt. Edward Porter Alexander made history by transmitting the first message in combat using signal flags over a long distance. Stationed atop "Signal Hill" in Manassas, Alexander saw Union troop movements and signaled to the brigade under Col. Nathan "Shanks" Evans, "Look out for your left, your position is turned", which meant that they were in danger of being attacked on their left flank.[18] Upon receiving a similar message, Gens. Beauregard and Joseph E. Johnston sent timely reinforcements that turned the tide of battle in the Confederates' favor.[19]
On the Union side, Myer attempted to deploy a military observation balloon at Manassas, bringing along 20 troops from the 26th Pennsylvania Infantry because of the lack of Signal Corps personnel that early in the war. Because of the haste of these untrained men, the balloon was damaged after a collision with a tree and could not be used for the battle.[20]
Fredericksburg
At the
Chancellorsville
During the Battle of Chancellorsville in May 1863, the performance of the Beardslee telegraph was so poor that Albert Myer soon decided to replace it. The campaign got off to a bad start because the chief signal officer of the Army of the Potomac, Captain Samuel T. Cushing, was kept in the dark about the plans of Maj. Gen. Joseph Hooker and he could not arrange his signal assets in advance. As the Army advanced, Cushing had insufficient wire on hand and was forced to use untested wire that had been left in the field, supported by iron lances, since Fredericksburg. On April 29, as the Army prepared to cross the Rapidan River, the Beardslee telegraph did not work, probably due to excessive wire length. Captain Frederick E. Beardslee, son of the inventor, was sent to make repairs. He found that the machine had been hit by lightning and was operating erratically. That evening a telegraph reached headquarters from the Ford on the Rapidan at 10:30 p.m., but it was marked (incorrectly) as originating at 5:30 p.m. Maj. Gen. Daniel Butterfield, Chief of Staff of the Army of the Potomac, told Cushing that he was not going to wake the commanding general for any telegram that was five hours late; his repose was "worth more than the commissions of a dozen signal officers." The inadequate wires and the unreliable telegraph caused persistent problems and kept General Hooker isolated from his forces in the Wilderness. On May 1, operators of the U.S. Military Telegraph Service were ordered to replace the Signal Corps Beardslee operators.[21]
It was also at Chancellorsville that a major change happened in Union signal security. Butterfield was concerned about Confederate interception of aerial telegraphy signals, but he used this as an advantage, ordering deceptive messages to be transmitted early in the campaign to mask the Union Army's true intentions. Since the Union signal corpsmen could routinely decipher Confederate messages, Butterfield was able to confirm that his bogus messages had been received. It was after these incidents that the Union began deploying the cipher disc devices and improving the security of their messages.[22]
Gettysburg
The
See also
Notes
- ^ Raines, pp. 5-6; Brown, pp. 20-22.
- ^ Raines, p. 5.
- ^ Raines, pp. 5-6; Brown, pp. 21-22.
- ^ a b Eicher, p. 402.
- ^ Raines, pp. 7, 12, 33.
- ^ Raines, pp. 7-8; Brown, pp. 25-34.
- ^ Raines, pp. 9-11; Brown, pp. 46-77.
- ^ Raines, pp. 12-13.
- ^ Raines, pp. 13, 17-22.
- ^ Raines, pp. 22-23.
- ^ a b c Scheips, Civil War History article.
- ^ Raines, p. 29.
- ^ a b Brown, pp. 205-09; Raines, pp. 29-30.
- ^ a b Raines, pp. 13-14.
- ^ Brown, pp. 93-97.
- ^ a b Raines, pp. 18-21.
- ^ Brown, pp. 99-102, 118-19; Raines, p. 16.
- ^ Brown, pp. 43-45; Alexander, pp. 50-51. Alexander recalls that the signal was "You are flanked."
- ^ Heidler, pp. 29-31.
- ^ Raines, p. 23.
- ^ Sears, pp. 194-96.
- ^ Sears, pp. 121-22.
References
- ISBN 0-8078-4722-4.
- Brown, J. Willard. (1974) [First published 1896 by U.S. Veteran Signal Corps Association]. The Signal Corps, U.S.A. in the War of the Rebellion. New York: Arno Press. ISBN 0-405-06036-X.
- Cameron, Bill (2000). "Albert James Myer". In Heidler, David S. & Heidler, Jeanne T. (eds.). Encyclopedia of the American Civil War: A Political, Social, and Military History. New York: W. W. Norton & Company. ISBN 0-393-04758-X.
- Eicher, John H. & ISBN 0-8047-3641-3.
- Heidler, David S. & Heidler, Jeanne T. (2000). "Edward Porter Alexander". In Heidler, David S. & Heidler, Jeanne T. (eds.). Encyclopedia of the American Civil War: A Political, Social, and Military History. New York: W. W. Norton & Company. ISBN 0-393-04758-X.
- Raines, Rebecca Robbins (1996). Getting the Message Through: A Branch History of the U.S. Army Signal Corps. Army Historical Series. Washington, DC: ISBN 0160453518.
- Scheips, Paul J. (December 1963). "Union Signal Communications: Innovation and Conflict". Civil War History. 9 (4): 399–421. S2CID 144182764.
- ISBN 0-395-87744-X.
Further reading
- Plum, William Rattle The Military Telegraph During the Civil War in the United States: With an Exposition of Ancient and Modern Means of Communication, and of the Federal and Confederate Cipher Systems; Also a Running Account of the War Between the States. (Vol. 1, Vol. 2). New York: Jansen, McClurg & Company, 1882.