Glossary of Mid-19th Century Telegraphic Terms
Copyright Signal Corps Association, 2004.  All rights reserved.

A wealth of useful information for new and experienced researchers and living historians.

(E-wire A&IGO to recommend new or report missing terms, additions or corrections ~ please also include your sources)
SCA Glossary of Terms (revis’d to January 26th. 2004)



Armature ~ any part of an electric machine or device that vibrates under the influence of a magnetic field or within which an electromotive force is induced.


Bain Code ~

Beardslee ~


Call ~

Cart ~ for signal purposes a light duty two-wheel’d conveyance or dray supported upon springs, fashioned after, or being designed as a Finley or Coolidge ambulance and used in conjunction with Flying Telegraph trains

Chappe Semaphore Telegraph System ~

Cipher ~

Cipher Code~

Cipher, Confederate ~

Cipher Disk ~

Cipher Key ~

Cipher Machine ~

Cipher Reel ~

Cipher Wheel ~

Code  ~ Any cryptographic system in which arbitrary symbols (or groups of symbols) represent units of plain text of regular length, usually single letters; units of plain text are rearranged; or both, in accordance with certain predetermined rules.

Code of Abbreviations ~

Code, Four Element ~

Code, General Service ~

Code, Homographic ~

Code, Military ~

Conductor ~ any material (e.g., copper) which allows an electrical charge to flow through it.

Confederate Code ~

Confederate Court Cipher ~

Confederate Military Telegraph ~

Corps ~ the Articles of War uses the word ‘corps’ in the sense of recognizing a portion of the army to have been organized by law with a head and members.  The Confederate Army Signal Corps was established by law in February of 1862 while the United States Army Signal Corps was authorized by law as a permanent organization in March of 1863

Court Cipher ~

Cryptogram ~


Current ~ Term used to describe electrical charges moving through a wire.


Daniel's Battery ~


Early Telecommunications ~

Electric Telegraph ~ instruments used in sending and receiving messages excited by the introduction of battery current, electrical signals can be transmitted nearly instantaneously over great distances. An electrically operated device or system for distant communication by means of visible or audible signals.

Electromagnet ~ Works just like an ordinary magnet except that it only attracts while electricity is passing through its coil.


"Faraday" ~ Michael Faraday, a pioneer of electrical technology

Field Telegraph ~

Flying Telegraph ~


Grove Battery ~

Gutta Percha ~ A type of rubber obtained from the gutta percha tree, native of Malaysia.



Inner Disk ~

Insulation ~ The insulating layer was invariably made from commercial gutta, a mixture of the gum gutta-percha (which was shipped in from the Far East), resin and water. Good-quality gutta was tough, water resistant and durable.

Insulator ~ Any material (e.g., glass) which does not allow an electrical charge to flow through it.



Key ~

Key Phrase ~

Key Word  ~ Brown p. 118


Lance ~

Lance Pole ~

Lance Post ~

Lance Posts ~

Lance Socket ~

Light Lines ~

Light Wagon ~ official term given to all other wagons not fitting the description of a heavy government contract wagon

Lineman’s Key ~

Line of Communication ~ a series or chain of stations so linked as to connect two or more distant positions within a theatre of operation.  Various modes of communication methods, i.e. wire telegraph, courier, flag/torch, etc., may be linked to-gether to form the line


Magneto ~

Magneto Telegraph ~

Magneto Electric Telegraph ~

Manifold Writer ~

Metal Wire Reel ~

Military Command ~

Military Communications ~

Military Communication Techniques ~

Military Field Communications ~

Military Telegraph ~

Military Signal Systems ~

Military Field Signals ~ those signalling systems most employed while an army is operating on campaign and otherwise said to be operating in the field

Morse Code ~ Code originally invented prior to 1844 by Alfred Vail and used by he and Samuel Morse to transmit letters as short electrical signals (dots) and long electrical signals (dashes) and soon thereafter called the "American" Morse Code. International, or Continental Code, as it was called in the mid-nineteenth century, was adopted at a conference on Berlin, Germany during 1851, for use in Europe and England. Continental Code was also used during the 1858 Trans-Atlantic cable.

Myer’s Manual ~ "A Manual of Signals: For The Use Of Signal Officers In The Field.”  By Col. Albert J. Myer, Signal Officer of the Army.  Washington, D.C. 1864


Naval Signaling ~

Needle telegraph ~ A device that required two or more lines to form a complete circuit.


Optical Telegraph ~ term usually associated with the fixed bladed signal system. (see: semaphore)


Pannier ~ lidded wicker of canvas framed baskets mounted upon either side of a pack saddle and used to carry signal supplies and pyrotechnics

Party ~ a group of two or more individuals traveling to-gether and given to co-operating in a common effort

Potomac Line, The ~ chain of stations established early in the war from Maryland Heights at Harpers Ferry to the fortifications of Washington running somewhat parallel to the Potomac River

Permanent Organization ~

Pliers ~ made of iron and carried in the signal haversack for adjusting or re-positioning cotton wicking in preparation for trimming same within a foot or flying torch light

Pocket Key ~

Polybius Code ~

Pre-concerted Code ~



Rebel Signal Corps ~ derisive term applied to indicate something to do with the Confederate Signal Corps

Receiving Signals ~ the physical or mechanical means of obtaining thought also referred to as” taking down signals”

Receipt  ~ a voucher or written acknowledgment, which should always be drawn up when official papers or materials are received or delivered.  The time of receipt should also be obtained

Recording Signals ~ (Myer ’64 p. 75)

Reconnoitre ~ war-like operations for the purpose of procuring information of the position and strength of an enemy

Register ~

Relay ~ Used to detect the weak current in telegraph cables (10-20mA). The relay translates the signal on the telegraph line into an equivalent signal in a local circuit. My be used in lieu of a sounder or in conjunction with one. Relays have a double set of binding posts (electrical connectors) instead of the set of two found on sounders.

Repeater ~ an intermediate station of communication visible from two other locations (usually elevated) and established on account of distance or physical obstacles

Repeating Signals ~

Rocket, Signal ~ (see Myer and Ord Manual)

Roundabout ~ popular short jacket used in Federal enlisted service.  Name is derived on account that the waist hem does not taper to a front and rear point as with a cavalry ‘shell’ but cut round-about  (Mathers)

Route Cipher ~


Scout ~ foot or horseman sent in advance, or on the flanks to give an account of the force and movement of an enemy

Secret Service ~

Secret Service Agent ~

Secret Service Operations ~

Section ~

Semaphore ~ Greek word sema sign, signal - an apparatus for signalling (as by the position of one or more movable arms). An apparatus for conveying information by means of visual signals, as with high poles or towers with pivoting blades or paddles, etc. Usually referred to as the telegraph prior to the introduction of the electric telegraph it is read when the blade or paddle is in a fixed position therefore it is a device for transmitting a code of permanent signals.

Semaphore Flag ~ a signal flag, two of which are used in a semaphoring manner, one in each hand

Semaphore Signaling ~ the making of long distance communication by fixed or permanent means of signaling using optical telegraphy

Semaphore System ~ a method of conveying (information) signals by or as if by semaphore

Semaphore Of Polybius ~

Semephore Telegraph ~ (see: Chappe)

Sending Signals ~ the physical or mechanical means of transmitting thought also referred to as “putting up” a message

Signals ~ various methods & systems used to direct troop movements, transmit observations and to co-ordinate information between separate elements on land, at sea and to convey balloon observation sightings from distant points using flags, telegraph or pre-concerted symbols hung from the basket. The term signaling or signaling also applies to systems of military communication

Signal Telegraph ~

Signalling ~ the act of transmitting information by means other than the unaided human voice. Signals can be visual, audible, or electrical and can be made by a variety of means, including torches, fusees, smokes, flags, lamps, pyrotechnics, drums, guns, or electric telegraph.

Sounder ~ A device for interpreting the signals coming off the telegraph cable without requiring the use of a paper generating register. Every time a Morse key or transmitter is depressed, the circuit becomes electrified and the armature, poised atop the wound electric coils, will be drawn down sharply toward the now energized electro-magnetic coils sitting vertically on-board a sounder. Meanwhile, at the other end of the line, another sounder is also responding identically causing a corresponding downward 'clack.' sound at the distant station (or series of them). When the key is let go or released by the lack of magnetic pull, a tension spring pulls the armature back up in its tuning fork case, causing a higher toned ‘click.’

Splice ~ To join two cables by interweaving the strands.

Spy Key ~

Staff ~

Station of Communication ~

Station of Observation ~

Strategic Cipher ~

Strategic Communications ~

Submarine Cable ~ submarine cable (under water use) consisted of copper conductors insulated with India rubber and varnish. Jute Yarn which acts as a cushion between the cable-core, the inner sheathing of iron cables, provides mechanical insulation.

Systematized Signals ~ signals formed under rules

System of Signals ~ all of those signals which can be devised based upon the changes, combinations, arrangements and repetitions which can be made with any given number of sorts of elementary signals


Tactical Cipher ~

Tactical Communications ~

Tactics ~ the art of drawing up and moving troops systematically

Telecommunications ~ refers to long-distance communication (the Greek tele means "far off"). Such communication is, in some instances, carried out with the aid of the transient systems of communication like aerial and wire telegraphs. In earlier times, smoke signals, drums, fixed light beacons, and various forms of signals, such as permanent signal systems of semaphores, were used for the same purpose. The information that is transmitted can be in the form of voice, symbols, pictures, text, or a combination of these. The physical equipment of a telecommunication system includes a transmitter or originator, one or more receivers, and a channel or means of communication, i.e. air, water, flags, rockets, electric telegraph wire, submarine cable, or some combination of these. The process of communicating over a long distance.

Telegraph ~ a device or contraption, which enables a detailed message to be sent instantaneously between two locations.

Telegraph Battery Wagon ~

Telegraph Blank Form ~

Telegraph Circuit ~

Telegraph Company ~

Telegraph Construction ~

Telegraph Construction Corps ~

Telegraph Corps ~

Telegraph Instrument ~

Telegraph Instruments ~

Telegraph Key ~ a correspondent used in transmitting messages in a code of signals over electric wires. Metallic lines are erected from one point to another and an electric current is either allowed to flow through the circuit or interrupted by a switch called a telegraph key closure lever. The anvil or the key is held away from the contact point by a spring. Depressing the key onto the contact point reconnects the circuit.

Telegraph Operator ~

Telegraph Pole ~

Telegraph Poles ~

Telegraph Register ~

Telegraph Relay ~

Telegraph Service ~

Telegraph Sounder ~

Telegraph Wagon ~

Telegraph Wire Reels ~

Telegrapher ~

Telegraphic Dispatch ~ a written message that has been sent by telegraph.

Telegraphic Signal ~

Telegraphist ~

Telegraphy ~ comes from Greek. Tele meaning distant and graphein to write.

Test Key ~ see: lineman’s key

Topography ~ the study of natural features of positions with a view of determining lines of communication or, in the case of stations of observation, as in developing maps to turn them to account in the possible first disposition of battle, and its various succeeding phases

Transmitting Signals ~

Transposition Cipher ~ a post-war term used to describe Route Cipher.  Also referred to in modern terms as the Route Transposition Cipher


US Military Telegraph ~

United States Military Telegraph ~

United States Telegraph ~ name of commercial telegraph company created during the early 1860’s

USMT ~ abbreviation for the war-time service known as the United States Military Telegraph

USMTC ~ generally a post-war designation applied by those wishing to refer to the United States Military Telegraph as a corps of operators.  An inappropriate usage


Vest Key ~

Vest Pocket Key ~

Vigenere ~

Vigenere Cipher ~ see: Vigenere Cipher Page

Vigenere Square ~ see: Vigenere Square Tool Page | View/Download the Vigenere Square (pdf file)


War Department Cipher~

Wire Cart ~

Wire Insulation ~ a coating of vulcanized rubber or gutta-percha surrounding a strand of telegraph wire to inhibit escapement of current while a telegraph line is in service.   Wire insulation allows the laying of telegraph wire upon the ground or even below the surface of water as in submarine cable

Wire Insulator ~ a telegraph wire suspended on poles or lances is attached to insulators to prevent the escape of the current to the earth at the points of support.  Glass, porcelain, rubber and glass shod iron insulators are used.  The broken necks of bottles can also be pressed into service for temporary lines when needs must

Wire Reel, Metal ~

Wire Spool ~

Wood Wire Reel ~

Wooden Wire Reel ~



Yankee Signal Corps ~ a derisive term to denote the Union or Federal Signal Corps