I always have to recommend Mother Earth, Mother Board by Neal Stephenson[1] if the thought of undersea cables sounds at all interesting. I'll also second andyjohnson0's recommendation of The Victorian Internet[2] - it blew my mind how much of modern digital culture existed on telegraphs prior to voice.
An interesting book on the subject of telegraph networks is The Victorian Internet by Tom Standage [1]. As well as the technical and commercial drivers, it also describes how the telegraph forced people to confront concepts like simultaneity, information being distinct from its physical medium, privacy, early approaches to encryption, etc. A fascinating book.
The GBP/USD currency pair is still known just as "the cable".
Aside from all its other uses: the telegraph gave a way to synchronize clocks. And accurate time is accurate measurement of distance.
> [...] The latest determination in 1892 is due to the cooperation of the McGill College Observatory at Montreal, Canada, with the Greenwich Observatory. [...] The final value for the longitude of the Harvard Observatory at Cambridge, as adjusted in June, 1897, is 4h 44m 31s.046 ±0s.048.
One of the major uses for the telegraph was the first funds transfers that could happen quicker than moving paper (or bullion) from one location to another. London banks would telegraph correspondent banks in India, Australia, etc.
This essentially doubled the capital intensity of international trade since the goods had to move in one direction but the money could be sent instantaneously in the other.
That book led me to Gutta Percha, the plastic-like coating on the wires used in these cables which was quite the innovation and made this all possible. Vulcanized rubber was the other option but performed poorly in cables and was harder to work with.
The above is a fascinating and depressing history of the Gutta Percha factory that made all these cables, after joining with the cable company that supplied the actual wires. There's an 1853 travelogue piece embedded here of an author visiting the factory, where he notes in the worst parts of the factory where boiling and heat are applied, it was staffed with boys who barely made more than a dollar a week. By boys I thought it was slang for young men then I realized 1850s England was heavily using child labor.
Those cables are the product of child labor, like much of the Victorian age's industrial and textile output. Children often made up significant portions of factory workforces, sometimes 25-50% in certain textile sectors, with many under 14. I wish the stories of child labor were better told and more prominent. This abuse and exploitation of children gets quite whitewashed during this age and its nice to see it acknowledged, albeit briefly.
At least in the UK the fact that the Victorians and others used a lot of child labour is well and widely known.
Blake wrote the poem The Chimney Sweeper about boys sold into the trade long before the 1850s and Elizabeth Barrett Browning published The Cry of the Children in Blackwood's magazine in 1843. Charles Kingsley used his The Water Babies to question child labour and England's treatment of the poor in general in 1862-3.
No one with any pretensions to knowledge of those times can claim not to know about child labour.
I've recommended that book on this board before. If you read it, I'd be curious about how you think it hits now, because part of its interest - I'd say insightfulness, at the time, but it now might risk anachronistic "charm" - was noting similar emergent behaviors between telegraph operators and early internet adopters. The technical content won't have dated, but the social parts may have.
When visiting Ayers Rock in Australia I stayed in Alice Springs. While I was there I learnt that Alice Springs exists because it was a repeater station for a telegraph line that stretched from Southern Australia all the way to London. There would be people listening to morse code, and tapping it out again to the next repeater station. Blew my mind that there was a wire that went all the way to London from Australia!
In the late-1700s/early-1800s the Admiralty Telegraph was used to relay messages between London and Portsmouth (70 odd miles apart) using a semaphore type system with repeater stations every 10 miles or so.
Yes, the Uk (southern England in particular) is dotted with "Semaphore Hill"s or "Telegraph Hills"s. There's one very close to where I'm sitting now, a few miles NE of Portsmouth.
In Tasmania, you can still see at least one semaphore station on Mt Nelson, which is above several suburbs on the south of the city of Hobart. I believe there was a semaphore route from the capital to Port Arthur (convict prison) and possibly other routes over the state too.
To think it was done even 1000s of years prior to that with just smoke and fire! Granted, the ability to communicate through the rain would be a necessity for the British.
My home country the Netherlands became a republic after a long war with the Spanish that controlled the territory from Spain after having inherited it via various wars and conflicts that divided up the remains of the Carolian empires. The Austrians ended up with a lot of states across what is now Germany and Belgium. France emerged as well as a country.
The Netherlands was too far away from the courts in Spain for them to govern effectively. Travel time was measured in weeks. So, remote regions like that necessarily had a large degree of autonomy. That became the basis for power to centralize around Amsterdam as it was favorably located for for trading. There were a lot of grievances with religious issues (Catholicism vs. Protestantism), taxation, etc. But the Spanish failure to project power from a distance had everything to do with the centralized nature of their empire and long communication channels.
In the so called golden century (17th century), the Netherlands got filthy rich on global trade and expansion. Information and knowledge flowed to and from Amsterdam from all over the world.
The Dutch naval forces dominated the North Sea for quite some time and it's only later that the British emerged as the better/bigger empire. Navies and ships were the fastest way to move information around at the time. Until the British finally upgraded to cables and telegrams which enabled them to have colonies on all continents. They really nailed command and control across their empire for a while.
The Romans had their roads to move armies and information. Shipping and navigation technology leveled that up from the 1400s or so. These days, low latency communication is a commodity of course.
They also got a tiny fraction of the rubber from cutting a whole tree down due to not finding a method to get all the rubber, and so cut almost all of the trees down
My wife and I were visiting County Kerry in SW Ireland last summer. We were on Valentia Island and quite by chance walked past the telegraph building where the first transatlantic cable came ashore. Only marked by a (very interesting) plaque describing its significance.
It was strategically important in WW1 because the British could communicate with the colonies with very chance little chance of messages being intercepted. The Germans, in contrast, didn't have access to their own transatlantic channels and had to use plain-text messages on cables that the UK/US controlled (US operators disallowed coded comms).
I love stories like this! Neil Stephenson has a great wired magazine article about information technology of that time, and telegraphs. The article is kind of a precursor to the ideas in his excellent book cryptonomicon. You should stop what you are doing and read that wired article. And then cryptonomicon if you haven't already done it. Best book to read over the rest of our holidays.
The book and the article are fascinating explorations of the impact of technology and cryptography on the world. The people who did the work to invent and build these worldwide systems were just like us (hackers, inventors, technologists), and we are just like them in a way. We all stand on the shoulders of giants.
Also I can't believe that article is 30 years old, boy I'm old.
The Cable that Changed the World (2024) is pretty nice on the topic. Shows us how, again, most of the things we consider "new" or at even revolutionary most showcase how historical ignorance.
Imagine people in 1890s or so, hearing about this almost instant transfer of messages, news to any part of the world - would be nothing short of magical modern technology.
If they had a positive outlook on technological development, yea. But that's cultural and perhaps didn't get into full swing until the mid 1900s and has now waned. Look at today how many pessimists hate LLMs despite them being even more magical modern technology.
If you enjoy this, you might like to read about the Zimmermann Telegram - British SIGINT that took advantage of this network, bringing the USA in to World War I.
Seeing the telegraph cross Canada like that reminded me of the network of hotels across Canada that were used by the wealthy on their way to the Orient from Europe during a bygone era.
... an era bookmarked at the end by the first live music broadcast transatlantic performance of Old Man River from a studio in NYC to a theater in London and that wasn't until 1957 and is a story all on its own
Over long distances, fibre optic would have lower latency so it'd be shorter if taking the same path today. But these signals would likely have been morse code and sent one-way at a time, so latency wouldn't have been noticed unless the repeaters were people rebroadcasting the signal (no idea how that was done).
I should have definitely qualified that statement. Technically, electrical signals over copper are "slowed down" less than light through fibre optic cables. However there's attenuation, electromagnetic interference, and other signal loss for electrical signals that (for long haul cables) will mean you will need repeaters that add significant amounts of latency. On top of that, the higher you try and up the frequencies, the worse these problems get.
For some medium-haul stuff, it wouldn't surprise me if you saw copper still being used for lower latency (eg between datacenter sites for flash-trading), but otherwise it's just not economical.
Ok, how does that work though? I understand the concept of lower attenuation since air/vacuum has less molecules to get in the way. Less repeaters, should have less system latency.
What I don't understand is how light is moving through what is a hollow bendable medium. Is the tube that it's in reflective and there's just less time it's passing through it? I guess that's the main one in commercial use to shave some time off, reading about it here: https://en.wikipedia.org/wiki/Photonic-crystal_fiber
I always have to recommend Mother Earth, Mother Board by Neal Stephenson[1] if the thought of undersea cables sounds at all interesting. I'll also second andyjohnson0's recommendation of The Victorian Internet[2] - it blew my mind how much of modern digital culture existed on telegraphs prior to voice.
[1] https://www.wired.com/1996/12/ffglass/
[2] https://news.ycombinator.com/item?id=46433901
https://archive.is/rs7Vq
An interesting book on the subject of telegraph networks is The Victorian Internet by Tom Standage [1]. As well as the technical and commercial drivers, it also describes how the telegraph forced people to confront concepts like simultaneity, information being distinct from its physical medium, privacy, early approaches to encryption, etc. A fascinating book.
[1] https://en.wikipedia.org/wiki/The_Victorian_Internet
The GBP/USD currency pair is still known just as "the cable".
Aside from all its other uses: the telegraph gave a way to synchronize clocks. And accurate time is accurate measurement of distance.
> [...] The latest determination in 1892 is due to the cooperation of the McGill College Observatory at Montreal, Canada, with the Greenwich Observatory. [...] The final value for the longitude of the Harvard Observatory at Cambridge, as adjusted in June, 1897, is 4h 44m 31s.046 ±0s.048.
-- https://adsabs.harvard.edu/full/1897AJ.....18...25S
71.12936 W; give or take about 2 metres: https://www.bing.com/maps/?v=2&cp=42.38148%7E-71.12936&style...
One of the major uses for the telegraph was the first funds transfers that could happen quicker than moving paper (or bullion) from one location to another. London banks would telegraph correspondent banks in India, Australia, etc.
This essentially doubled the capital intensity of international trade since the goods had to move in one direction but the money could be sent instantaneously in the other.
That book led me to Gutta Percha, the plastic-like coating on the wires used in these cables which was quite the innovation and made this all possible. Vulcanized rubber was the other option but performed poorly in cables and was harder to work with.
https://atlantic-cable.com/Article/GuttaPercha/
The above is a fascinating and depressing history of the Gutta Percha factory that made all these cables, after joining with the cable company that supplied the actual wires. There's an 1853 travelogue piece embedded here of an author visiting the factory, where he notes in the worst parts of the factory where boiling and heat are applied, it was staffed with boys who barely made more than a dollar a week. By boys I thought it was slang for young men then I realized 1850s England was heavily using child labor.
Those cables are the product of child labor, like much of the Victorian age's industrial and textile output. Children often made up significant portions of factory workforces, sometimes 25-50% in certain textile sectors, with many under 14. I wish the stories of child labor were better told and more prominent. This abuse and exploitation of children gets quite whitewashed during this age and its nice to see it acknowledged, albeit briefly.
At least in the UK the fact that the Victorians and others used a lot of child labour is well and widely known.
Blake wrote the poem The Chimney Sweeper about boys sold into the trade long before the 1850s and Elizabeth Barrett Browning published The Cry of the Children in Blackwood's magazine in 1843. Charles Kingsley used his The Water Babies to question child labour and England's treatment of the poor in general in 1862-3.
No one with any pretensions to knowledge of those times can claim not to know about child labour.
I imagine the percent of people who know these telegram cables were made by children is a very low percentage.
What difference does 10 years make when you are working in a shitty factory for peanuts?
Oh wow will definitely give that book a read, very interesting.
I've recommended that book on this board before. If you read it, I'd be curious about how you think it hits now, because part of its interest - I'd say insightfulness, at the time, but it now might risk anachronistic "charm" - was noting similar emergent behaviors between telegraph operators and early internet adopters. The technical content won't have dated, but the social parts may have.
I came here to recommend this fine book as well.
When visiting Ayers Rock in Australia I stayed in Alice Springs. While I was there I learnt that Alice Springs exists because it was a repeater station for a telegraph line that stretched from Southern Australia all the way to London. There would be people listening to morse code, and tapping it out again to the next repeater station. Blew my mind that there was a wire that went all the way to London from Australia!
> Blew my mind that there was a wire that went all the way to London from Australia!
Before the telegraph they used to do things wirelessly: https://www.brunningandprice.co.uk/_downloads/telegraph/tele...
(Not quite London to Australia though...)
In the late-1700s/early-1800s the Admiralty Telegraph was used to relay messages between London and Portsmouth (70 odd miles apart) using a semaphore type system with repeater stations every 10 miles or so.
Yes, the Uk (southern England in particular) is dotted with "Semaphore Hill"s or "Telegraph Hills"s. There's one very close to where I'm sitting now, a few miles NE of Portsmouth.
In Tasmania, you can still see at least one semaphore station on Mt Nelson, which is above several suburbs on the south of the city of Hobart. I believe there was a semaphore route from the capital to Port Arthur (convict prison) and possibly other routes over the state too.
https://www.utas.edu.au/library/companion_to_tasmanian_histo...
Sadly the semaphore pole itself is gone. The building is still there and was used until 1969.
To think it was done even 1000s of years prior to that with just smoke and fire! Granted, the ability to communicate through the rain would be a necessity for the British.
My home country the Netherlands became a republic after a long war with the Spanish that controlled the territory from Spain after having inherited it via various wars and conflicts that divided up the remains of the Carolian empires. The Austrians ended up with a lot of states across what is now Germany and Belgium. France emerged as well as a country.
The Netherlands was too far away from the courts in Spain for them to govern effectively. Travel time was measured in weeks. So, remote regions like that necessarily had a large degree of autonomy. That became the basis for power to centralize around Amsterdam as it was favorably located for for trading. There were a lot of grievances with religious issues (Catholicism vs. Protestantism), taxation, etc. But the Spanish failure to project power from a distance had everything to do with the centralized nature of their empire and long communication channels.
In the so called golden century (17th century), the Netherlands got filthy rich on global trade and expansion. Information and knowledge flowed to and from Amsterdam from all over the world.
The Dutch naval forces dominated the North Sea for quite some time and it's only later that the British emerged as the better/bigger empire. Navies and ships were the fastest way to move information around at the time. Until the British finally upgraded to cables and telegrams which enabled them to have colonies on all continents. They really nailed command and control across their empire for a while.
The Romans had their roads to move armies and information. Shipping and navigation technology leveled that up from the 1400s or so. These days, low latency communication is a commodity of course.
Similar history for Denver.
Fun facts, the subsea telegraph network cables coating were made from Gutta Percha [1].
Unlike normal rubber, it is a type of thermoplastic and it's a popular organic plastic before the petroleum based modern plastic become pervasive [2].
[1] The legacy of undersea cables:
https://blog.sciencemuseumgroup.org.uk/the-legacy-of-underse...
[2] Gutta-percha:
https://en.wikipedia.org/wiki/Gutta-percha
They also got a tiny fraction of the rubber from cutting a whole tree down due to not finding a method to get all the rubber, and so cut almost all of the trees down
Here is some more information: https://en.wikipedia.org/wiki/All_Red_Line
And one of the old cable huts still exists: https://en.wikipedia.org/wiki/Pacific_Cable_Station
Anyone visiting the South West of the UK should go visit https://en.wikipedia.org/wiki/PK_Porthcurno (https://pkporthcurno.com/)
(There's also the https://en.wikipedia.org/wiki/Minack_Theatre built into the cliff face nearby.)
(I've been to the theatre a number of times but never convinced my in-laws to visit the Telegraph Museum.)
My wife and I were visiting County Kerry in SW Ireland last summer. We were on Valentia Island and quite by chance walked past the telegraph building where the first transatlantic cable came ashore. Only marked by a (very interesting) plaque describing its significance.
There is also a small museum at the site, worth a look if you visit again! https://valentiaisland.ie/cable-station/
It was strategically important in WW1 because the British could communicate with the colonies with very chance little chance of messages being intercepted. The Germans, in contrast, didn't have access to their own transatlantic channels and had to use plain-text messages on cables that the UK/US controlled (US operators disallowed coded comms).
This forced Germans to build some of their own cables, super interesting history: https://blogs.mhs.ox.ac.uk/innovatingincombat/yap-island-ger...
I love stories like this! Neil Stephenson has a great wired magazine article about information technology of that time, and telegraphs. The article is kind of a precursor to the ideas in his excellent book cryptonomicon. You should stop what you are doing and read that wired article. And then cryptonomicon if you haven't already done it. Best book to read over the rest of our holidays.
Article in paywall at https://www.wired.com/1996/12/ffglass/
The book and the article are fascinating explorations of the impact of technology and cryptography on the world. The people who did the work to invent and build these worldwide systems were just like us (hackers, inventors, technologists), and we are just like them in a way. We all stand on the shoulders of giants.
Also I can't believe that article is 30 years old, boy I'm old.
The Cable that Changed the World (2024) is pretty nice on the topic. Shows us how, again, most of the things we consider "new" or at even revolutionary most showcase how historical ignorance.
Imagine people in 1890s or so, hearing about this almost instant transfer of messages, news to any part of the world - would be nothing short of magical modern technology.
If they had a positive outlook on technological development, yea. But that's cultural and perhaps didn't get into full swing until the mid 1900s and has now waned. Look at today how many pessimists hate LLMs despite them being even more magical modern technology.
If you enjoy this, you might like to read about the Zimmermann Telegram - British SIGINT that took advantage of this network, bringing the USA in to World War I.
https://en.wikipedia.org/wiki/Zimmermann_telegram
Seeing the telegraph cross Canada like that reminded me of the network of hotels across Canada that were used by the wealthy on their way to the Orient from Europe during a bygone era.
The original internet, more or less. Apparently whales liked to scratch themselves on some of the cables though.
here's an interesting series of videos on undersea cables, as described by... Tool Time from Home Improvement
https://youtu.be/zmyBSrQodnI?si=OpFZhiQeNn3ax58p
in this context: https://www.submarinecablemap.com/
... an era bookmarked at the end by the first live music broadcast transatlantic performance of Old Man River from a studio in NYC to a theater in London and that wasn't until 1957 and is a story all on its own
https://www.sciencemuseum.org.uk/objects-and-stories/robeson...
Is the latency the same now as it was for the signal itself? Obviously the throughput is rather different.
My understanding was that the latency was much higher due to manual repeating at stations along the way.
Eg. when the London-Mumbai telegraph was new it took around 45 minutes in one direction.
Over long distances, fibre optic would have lower latency so it'd be shorter if taking the same path today. But these signals would likely have been morse code and sent one-way at a time, so latency wouldn't have been noticed unless the repeaters were people rebroadcasting the signal (no idea how that was done).
> Over long distances, fibre optic would have lower latency so it'd be shorter if taking the same path today.
Source that claim, it's well understood the speed of light is around 66% due to refractive index in glass.
It gets weird with telegraph cables and capacitance, wikipedia at least touches on it here: https://en.wikipedia.org/wiki/Speed_of_electricity
I should have definitely qualified that statement. Technically, electrical signals over copper are "slowed down" less than light through fibre optic cables. However there's attenuation, electromagnetic interference, and other signal loss for electrical signals that (for long haul cables) will mean you will need repeaters that add significant amounts of latency. On top of that, the higher you try and up the frequencies, the worse these problems get.
For some medium-haul stuff, it wouldn't surprise me if you saw copper still being used for lower latency (eg between datacenter sites for flash-trading), but otherwise it's just not economical.
That's the point of hollow-core fibre which is absolutely being used where decreasing latency even by small amounts is worth it.
> That's the point of hollow-core fibre
Ok, how does that work though? I understand the concept of lower attenuation since air/vacuum has less molecules to get in the way. Less repeaters, should have less system latency.
What I don't understand is how light is moving through what is a hollow bendable medium. Is the tube that it's in reflective and there's just less time it's passing through it? I guess that's the main one in commercial use to shave some time off, reading about it here: https://en.wikipedia.org/wiki/Photonic-crystal_fiber
It works in that light will travel faster in a less dense medium. Remove the relatively denser glass for gas/vacuum.
Also the way fibre works is commonly misunderstood. The light isn't bouncing.