When India sends out what is being called the world’s last telegram on July 15, the sound of those last few dots and dashes will mark the end of an era.

Before there were phones, e-mails, texts or instant messages, the telegraph was the tool that made it possible for people over long distances to communicate with each other within the shortest time technologically possible.

In 2006, Western Union, which had been transmitting telegrams since 1851, delivered its last message in Morse code. India, the largest country that still uses the telegraph regularly, will send out the last dots and dashes over the wire before it too shuts down its telegraph in what’s being described as the world’s last telegram.

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Telegraph service is still available in some industrialized nations, but in such cases a telegram serves as more of a retro novelty than a practical means of communication. Given the speed with which new communications technologies emerge to quickly displace what came before, however, the telegraph has proven surprisingly resilient.

Before there was the telegraph, systems of communication using visual codes, such as smoke signals or beacons, existed for millennia. The electric telegraph, with its roots in the mid-18th century, was the mass communications tool of the industrial era.

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The telegraph presented a means with which to communicate over great distances, but what was lacking in the earliest telegraph designs was a practical system with which messages would be transmitted and interpreted. In the mid-1830s, Samuel Morse, along with his assistant Alfred Vail, changed that by devising a system of dots and dashes that would correspond to each letter of the English alphabet — Morse Code. A decade later, Morse’s system would be commercialized and deployed throughout the United States, and become the international standard of telegraphic transmission.

Just as the telephone and fax eventually made the telegraph obsolete, so too did the telegraph displace another means of information transmission: the horse rider. Shortly after completing the first transcontinental telegraph line in the United States in 1861, Western Union put the Pony Express, then the fastest means of getting a message from east to west, out of business.

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Five years after wires connected both coasts of the United States, a telegraph line was constructed that spanned the Atlantic Ocean, connecting the United States and Europe. By the end of the 19th century, every continent, except Antarctica, were interconnected by telegraph wire — the world’s first-ever global mass communications system.

The benefits of the telegraph were obvious and immediate: fast-moving (at least for the era) exchanges of information. Telegraphic communications were responsible for everything as mundane as striking a deal between parties exchanging goods or services to exceptional cases where a telegram saved lives or helped catch a killer. And as more miles of telegraph wire was lain down, the cheaper it became for the average person to send a telegram, making those benefits more broadly available.

Just as the 19th century would see the rise and eventual domination of telegraph communications, the 20th century would almost be a mirror image of that success, bringing about the telegraph’s decline. The popularization of the telephone in the first half of the 20th century, and later the Telex, the fax machine and e-mail in the second half would render the telegraph obsolete.

Photo: When India sends out what is being called the world’s last telegram, the sound of those last few dots and dashes will mark the end of an era. Credit: Corbis Images