The first hackers had telescopes

🕵️ This time, I went exploring nineteenth-century history and found a remarkable story: a group of financial speculators hacked a telecommunications network using gloves, stockings, and a telescope.

The year was 1834. There were no computers. There wasn't even an electrical telegraph network. And yet the essential ingredients of a modern cyberattack were already present.

The first hackers had telescopes

Restored examples of France's optical telegraph.

An internet made of wooden arms

In the early nineteenth century, France operated an extraordinary communications network invented by Claude Chappe.

Hundreds of towers stretched across the country, each equipped with enormous articulated wooden arms.

An operator watched the neighboring tower through a telescope. When its arms moved into a new position, he copied the configuration on his own tower.

His neighbor copied it, and so on.

In this way, messages could travel hundreds of kilometers in hours rather than days.

Remarkably, most operators didn't know what the messages meant. They simply reproduced the configurations. Only certain officials possessed the necessary codebooks. (Art Waste)

Enter the Blanc brothers

In Bordeaux, twin brothers Louis-Joseph and Louis-François Blanc were trading French government bonds.

Their problem was information. They needed to know what had happened at the Paris stock exchange. Unfortunately, the news traveled by mail coach, arriving well after the relevant trading session.

The government, meanwhile, had its magnificent optical telegraph.

The brothers couldn't legally use it.

So they decided to use it illegally.

They recruited an accomplice in Paris and bribed telegraph operators at Tours.

Here the story becomes delightfully ingenious.

The Parisian accomplice sent actual gloves when bond prices rose and stockings or cravats when they fell. These articles traveled by ordinary post to Tours. An operator there translated the information into telegraph signals.

But how could he introduce private information into government communications without exposing the deception?

He exploited the network's error-correction procedure.

Whenever an operator made a mistake, he could transmit a special signal meaning that the preceding character should be disregarded.

The conspirators inserted a particular false character into an official message, immediately followed by this correction signal.

Thus, the final decoded government message remained unchanged.

But another accomplice near Bordeaux, watching the telegraph arms through a telescope, could observe the supposedly erroneous character and extract the hidden financial information.

The error was the message.

The mechanism is documented in the contemporary prosecution records, examined in a particularly detailed historical reconstruction published in September 2026. (Art Waste)

The problem nobody had anticipated

The scheme operated from 1834 to 1836.

Eventually, suspicions arose, and the conspiracy was uncovered.

The brothers and their accomplices faced trial in March 1837.

The jury found that the operator had sent unauthorized signals and accepted inducements.

But the bribery law required that the payment concern an act belonging to the official's duties. The jury decided that transmitting false signals was not such an act.

The resulting legal outcome did not amount to an endorsement of their conduct.

France subsequently enacted legislation against unauthorized telegraphic signaling in May 1837. (Art Waste)

And then Alexandre Dumas entered the picture

Here is my favorite discovery.

In The Count of Monte Cristo, serialized beginning in 1844, Edmond Dantès visits an optical telegraph station.

He bribes its operator to transmit false information about political developments in Spain.

The misinformation reaches Paris, causes panic in the bond market, and inflicts enormous financial losses on his enemy Danglars.

It's essentially a fictional exploitation of the same vulnerability.

Dumas even emphasizes that the telegraph operators don't understand the messages they relay.

Whether he consciously drew on the Blanc affair is uncertain, but the resemblance is striking. (American Literature)

What I found most interesting

The whole story is sometimes described as the first cyberattack, although that designation is inevitably anachronistic and debatable.

What interests me is something else.

The telegraph network was designed around an elegant separation of functions: operators transmitted messages without understanding their content, while officials interpreted them.

This arrangement was supposed to ensure secrecy.

But the attackers realized that information could reside not just in the official messages, but also in the mechanism used to transmit and correct them.

The network had two simultaneous meanings: one for its intended recipients and another for someone watching its operations.

Nearly two centuries later, we still encounter the same general idea in covert communication channels.

And I particularly love one small detail from the historical investigation.

The court records reveal that other speculators had developed their own communications systems. Near Angoulême, a chain of windmills reportedly conveyed market information through the positions of their sails.

One day, a window was accidentally left open during a festival, producing an erroneous signal.

An entire financial information network, defeated by an open window. 🌿

For anyone curious, this historical reconstruction based on the 1837 court records is fascinating. It even includes an interactive demonstration of the intercepted telegraph signals.