Background information
No longer glamour, but dust: "Mafia 4" and the harsh everyday life of Sicily around 1900
by Kim Muntinga
Telegraphy – the Internet of the 19th century
27.5.2025
Translation: Megan Cornish
Telegraphy was already being used to transmit messages and images over 150 years ago, and photo and wireless transmission followed at the beginning of the 20th century. Global data networking isn’t all that new.
The world didn’t just become connected with the Internet. Before that, there was the telephone network – which could also be used for data transmission, via fax machines, for example. But the telephone network wasn’t the first global communications network. A global network had already been built in the 19th century – the telegraph network.
Telegraphy changed the world in a similar way to the Internet. Before telegraphy, there was no way to transmit messages quickly over long distances, so people relied on the post. An undersea cable being laid across the Atlantic drastically reduced the transmission time for messages from several weeks to a few hours. From the very beginning, telegraphy was very important for journalism, as well as for political and economic decision-making.
When I say telegraphy in this article, I always mean electrical telegraphy. Humans have long used other forms of telegraphy: messages can be transmitted using coded light signals or acoustically using drums, but their range is limited in comparison.
How does telegraphy work?
Telegraphy’s based on the movement of electricity along a wire. At one end of the wire is an input device, and at the other, a receiving device. In its original form, the input device is extremely simple: it’s just a button. Pressing it closes the circuit and sends current through the wire. When the button’s released, it breaks the circuit.
Similar to tapping, the sequence of signals and pauses can create a code, allowing information to be transmitted. Morse code has become the established standard for this, consisting of short signals – recorded as dots – long signals – recorded as dashes – and pauses. In the Morse alphabet, letters, numbers and special characters can be encoded into electrical signals and then decoded.
..-. ..- -. / ..-. .- -.-. - ---... / -.. . .-. / -- --- .-. ... . -.-. --- -.. . / ... - .- -- -- - / .. -. / ... . .. -. . .-. / .... . ..- - .. --. . -. / ..-. --- .-. -- / --. .- .-. / -. .. -.-. .... - / ...- --- -. / ... .- -- ..- . .-.. / -- --- .-. ... . .-.-.- / -.. . .-. / . .-. ..-. .. -. -.. . .-. / -.. . ... / ... -.-. .... .-. . .. -... - . .-.. . --. .-. .- ..-. . -. / .-.. . .. ... - . - . / .- -... . .-. / -.. .. . / ...- --- .-. .- .-. -... . .. - .-.-.-
At the other end of the line is a pen that records these signals as deflections on a moving strip of paper – a writing telegraph. Later, these signals could also be converted into a beep. This was easier for a skilled telegraph operator, as they were able to translate the Morse code as they heard it and write down the message.
The beginnings of the telegraph network
The physical principles of electrical telegraphy were already known to scientists in the early 19th century. Numerous inventors experimented with electrical signal transmission, but there was no standardised method, and the practical benefits weren’t yet clear. Lines were short too. A line in Göttingen between the workplaces of mathematician Carl Friedrich Gauss and physicist Wilhelm Eduard Weber was one kilometre long. That was considerable back then.
The lines were often laid along railway lines. This also allowed information about the trains to be transmitted. For a time, the railway was a safe method of escape for robbers, as nothing was faster than a moving train. Telegrams changed that. Staff at train stations were informed about the criminals and lay in wait with handcuffs.
Submarine cables: an adventure
Underwater cables presented a particular challenge. In 1850, the first submarine cable was laid between France and England. Despite the short distance, it only lasted a few hours due to a lack of suitable, durable insulation material.
A world becoming connected
This map from the early 20th century shows how many submarine connections already existed. Even small islands in the middle of the ocean were accessible. There was even a connection across the Pacific from Australia to Vancouver.
Also, only one message could be sent through a line at a time to start with, although multiplexing later made it possible to send a few simultaneously. As a result, many earlier messages reached their destination via detours because the direct route was already in use. Limited capacity and manual forwarding made telegrams very expensive. Ordinary people only used them in urgent or important situations.
Phototelegraphy
The telegraph network was also used to transmit images. As early as 1855, Italian physicist Giovanni Caselli patented a device he called the pantelegraph. It could transmit simple images up to 10×15 cm in size. It was used primarily in France from 1860 onwards for verifying signatures in banking transactions, among other things.
The images had to be drawn with ink on a zinc foil. Zinc conducts electricity, but ink doesn’t. A machine scanned the foil. If it detected zinc, it sent an electrical signal – if it didn’t, it wouldn’t. This transmitted a negative to the receiver as a result.
Édouard Belin also developed a picture telegraph at the beginning of the 20th century. The first successful photographic transmission across the Atlantic was in 1921. The techniques of picture telegraphy were continually developed, with the devices primarily using the telephone network in the 20th century. From 1926 onwards, it was also possible to transmit images wirelessly via radio. Although the so-called Fultograf was a flop, it was also the forerunner of TV and fax.
Wireless telegraphy
In 1886, Heinrich Hertz proved the existence of radio waves. This laid the foundation for developing radio broadcasting and radio telegraphy. 1897 marked the first transmission across the open sea near the Bristol Channel over a distance of just under five kilometres. Much greater distances were soon achieved and, in 1901, radio pioneer Guglielmo Marconi achieved the first wireless transmission across the Atlantic.
Radiotelegraphy was important for shipping. Previously, ships weren’t able to communicate with the outside world if they were in distress at sea. In 1906, the SOS distress call was introduced. The combination of letters didn’t mean anything specific, but was chosen because it was a very simple Morse code sequence: three dots, three dashes, three dots.
The Titanic, which struck an iceberg and sank in 1912, was able to communicate with other ships via radiotelegraphy. This was the only reason that some passengers survived.
Sound telegraphy (aka telephone)
The telegraph network was the first step toward telephony, but it was only partially suitable for the telephone. Telephony requires higher transmission quality, so the telephone network was initially expanded primarily over short distances at a local level.
A gradual end
In Switzerland, the state-owned PTT (Post, Telephone, Telegraph) was split into Swiss Post and Swisscom in 1998. As a result of this split, the telegram service – which had become virtually insignificant – was discontinued in 1999. In Germany, telegrams could still be sent until the end of 2022, but only within the country.
David Lee
Senior Editor
David.Lee@digitecgalaxus.chMy interest in IT and writing landed me in tech journalism early on (2000). I want to know how we can use technology without being used. Outside of the office, I’m a keen musician who makes up for lacking talent with excessive enthusiasm.
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