History of Telegraphy in Timeline

By Popular Timelines Editorial Team · Updated: February 15, 2026

Telegraphy is long-distance communication using symbolic codes, differentiating it from physical message delivery methods like pigeon post. Unlike ancient signaling systems with predetermined messages, true telegraphs can transmit arbitrary text. Flag semaphore is an example. This highlights telegraphy's core function: encoding and transmitting detailed information over distance without physical conveyance.

1900: Invention of the Bildtelegraph

Around 1900, German physicist Arthur Korn invented the Bildtelegraph, which became widespread in continental Europe.

1900: Telegraph in decline

By 1900, the telegraph was definitely in decline despite continued traffic growth between 1867 and 1893 despite the introduction of the telephone in this period.

1901: Marconi sends signals across the Atlantic

In 1901, Marconi sent wireless signals across the Atlantic, demonstrating the potential of radio communication.

1901: Tesla's wireless power station application

In 1901, Nikola Tesla began a large-scale application of his wireless power ideas with a high-voltage power station, now called Wardenclyffe Tower.

1902: Discovery of the ionosphere

In 1902, a study of Marconi's demonstrations of radio led to the discovery of a radio reflecting layer in the Earth's atmosphere, later called the ionosphere.

1904: Marconi begins commercial news service to ships

In 1904, Marconi began the first commercial service to transmit nightly news summaries to subscribing ships.

October 1907: Regular transatlantic radio-telegraph service begins

On 17 October 1907, a regular transatlantic radio-telegraph service was finally begun.

1908: Transmission of a wanted-person photograph from Paris to London

In 1908, a widely noticed transmission of a wanted-person photograph from Paris to London used the Bildtelegraph.

1915: Decline of the heliograph

From 1915 onwards, the use of the heliograph declined, but it remained in service in Britain and British Commonwealth countries for some time.

1919: Central Bureau for Registered Addresses established

In 1919, the Central Bureau for Registered Addresses was established in New York City to help ease message delivery problems.

1920: Permanent decline of telegraph use

Around 1920, telegraph use began to permanently decline, primarily due to the growth in the use of the telephone.

1920: Telegraph decline begins

From 1920 onwards, the telegraph began to decline due to competition from the telephone, which diminished the telegraph's speed advantage. The few remaining telegraph applications were largely taken over by alternatives on the internet towards the end of the 20th century.

1923: British companies owned 42.7 percent of world's cables

By 1923, British companies owned and operated 42.7 percent of the world's cables, continuing their dominance in submarine cable systems.

1926: Telex development begins in Germany

In 1926, Telex development began in Germany.

1929: Invention of the Hellschreiber

In 1929, German inventor Rudolf Hell invented the Hellschreiber, a pioneer in mechanical image scanning and transmission.

1929: Peak telegram usage

In 1929, telegrams reached their peak usage, with an estimated 200 million telegrams sent.

1933: Telex becomes operational in Germany

In 1933, Telex became an operational service run by the Reichspost in Germany.

1934: 28,000 codes registered at the Central Bureau

By 1934, 28,000 unique code names for telegraph addresses had been registered at the Central Bureau.

1942: Heliograph used in Western Desert Campaign

In 1942, Australian forces used the heliograph in the Western Desert Campaign of World War II.

1950: Mean length of telegram in the UK

According to a study, the mean length of the telegrams sent in the UK before 1950 was 14.6 words or 78.8 characters.

July 1957: Telex introduced to Canada

In July 1957, Telex was introduced into Canada.

1958: Telex introduced to the United States

In 1958, Telex was introduced to the United States.

1963: Introduction of ASCII code

In 1963, the American Standards Association introduced ASCII, a seven-bit code supporting a larger number of characters than Baudot, including upper and lower case letters.