So I was curious what this was called by contemporaries, because "optical telegraph" seems like an overly-specific construction.
And sure enough, Wikipedia tells us that its inventor, Claude Chappe, coined the terms semaphore and tachygraph, while a French statesman preferred to apply the novel term telegraph.
"Optical" was clearly applied in retrospect, after its electrical counterpart came on the scene.
Fun semaphore fact: the Peace Symbol, popularized along with the smiley face by hippies, is a superposition of two semaphores: "N" and "D", meaning "Nuclear Disarmament".
If you like this, you will surely enjoy The Victorian Internet by Tom Standage. It talks about the optical telegraph and the electric one, and more than the technology, the culture that developed around the telegraph.
If nothing else, download the free Kindle sample, or read the preface and comments on Tom's site and see for yourself.
One of my favorite chapters is Love over the Wires:
> Spies and criminals are invariably among the first to take advantage of new modes of communication. But lovers are never far behind. There are no known examples of amorous messages being passed over the optical telegraph, since it was not available for general public use; but within a few months of the electric telegraph being opened to the public, it was being used for something that even the most farsighted of telegraph advocates had never dared to imagine: to conduct an on-line wedding...
> with the telegraph operators relaying their words to and fro in Morse code, the two were duly wed by the magistrate. "The exchange of consent being given by the electric flash, they were thus married by telegraph," reports a contemporary account.
Yep, that's where I stumbled onto this. The Victorian Internet was fun but way too short.
A few chapters in David Nasaw's Andrew Carnegie and Edmund Morris's Edison go into telegraph history a bit.
I got into the subject after reading both those books (they both got their start as telegraph operators), and noticing the similarity in meritocracy and culture between programmers today and telegraph operators back then.
I'd love to read more. Two other books on my list are Lincoln In The Telegraph Office (1907) and Submarine Telegraphy (1898). All the in-depth books on the telegraph seem to have been written 100 years ago basically.
Agreed. This book is great. I stumbled across it while researching a steampunk RPG I was making years ago & instantly fell in love with it. Highly recommend it.
At the beginning of the 19th century, it was possible to wirelessly transmit a short message from Amsterdam to Venice in one hour’s time. A few years before, a messenger on a horse would have needed at least a month’s time to do the same.
...the low-tech predecessor of electronic mail more or less obtained the same result without wires or energy, while the internet consists of a cluster of cables and is devouring our energy resources at an ever faster pace.
So cool and I had never heard of it. You hear far more about how means of travel have sped up. We tend to kind of overlook the importance of speed of communication.
(And I read the entire thing thinking of Gandalf lighting the signal fire without permission via the help of a hobbit...)
Assuming friendly territory, we have a distance of 1164 km by the path of modern roads. At walking pace, the average distance expected to cover in Europe was 30 km, so around 40 days.
Taking the speed of a horse into account, and the prevalence of roads in Germany and the Netherlands after crossing the apls, the horse rider should be able to make it with quick pace in 10 days.
I stumbled upon one while hiking the Swedish coast north of Stockholm [https://www.atlasobscura.com/places/den-optiska-telegrafen-t...]. We took a minute or so to guess what it could be before reading the explanation plate. It impressively allowed communication through the baltic towards Åland.
In parallel, regular "snail mail" was brought from mainland Sweden to Åland along a similar route, but through a peasant relay. Local farmers were obliged by the state to move bags of mail to the next farmers. And the coastal ones were taking turns to sail the 44 km to Åland all year round.
its crazy to think that this technology could have been used in the roman empire or any prior civilization that had a written language. personally i would use large billboard with a black/white pattern and a mask that slides back and forth to change the color of the billboard from white to black very suddenly and repeatedly. it could be seen for miles without a telescope.
The ancient Greeks had a "hydraulic telegraph", in which to posts within eyesight of one another could communicate by fire.
The length of the fire was measured by water spilling out of a reservoir, and the message indicated by the level to which the water fell during that period.
Limited number of signals which could be sent, and limited range and hours of operation, but an option.
Note that the Chappe Telegraph benefited by availability of optics and telescopes, which the Greeks lacked.
A British hydraulic telegraph was developed in 1838 which relied on pressure transmitted through pipes, though it was never fully developed. This could operate at distances of up to a mile and had a vocabulary of 12,000 words.
In the 9th century the Byzantines operated an optical beacon system also based on hydraulic telegraphs.
Other long-distance signalling methods include drumming (particularly prevalent in Africa, and characterised by "drum languages": <https://en.wikipedia.org/wiki/Talking_drum>), signal fires, and mirrors, though I'm not aware of the latter being used in ancient times.
There optical telegraph and its semaphores featured crucially in Alexandre Dumas's 1845 book "The Count of Monte Cristo" and were depicted in multiple film versions.
Fraud happened on this network. I learned this at the "Musée des Arts et Métiers" in Paris.
From this Wikipedia article [0] :
The network was reserved for government use, but an early case of wire fraud occurred in 1834 when two bankers, François and Joseph Blanc, bribed the operators at a station near Tours on the line between Paris and Bordeaux to pass Paris stock exchange information to an accomplice in Bordeaux.
That’s an example of the optical telegraph the article is about. A person inside uses levers to move those arms into different positions. Each position has a meaning, similar to naval flags. Other towers in visual range can then re-transmit the message to towers further down range.
And sure enough, Wikipedia tells us that its inventor, Claude Chappe, coined the terms semaphore and tachygraph, while a French statesman preferred to apply the novel term telegraph.
"Optical" was clearly applied in retrospect, after its electrical counterpart came on the scene.
Fun semaphore fact: the Peace Symbol, popularized along with the smiley face by hippies, is a superposition of two semaphores: "N" and "D", meaning "Nuclear Disarmament".