5 ms·

The British empire's resilient subsea telegraph network

228 points by giuliomagnifico 10mo ago

jphoward 10mo ago
Here is some more information: https://en.wikipedia.org/wiki/All_Red_Line 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 https://en.wikipedia.org/wiki/Pacific_Cable_Station
- alexfoo 10mo ago
  Anyone visiting the South West of the UK should go visit https://en.wikipedia.org/wiki/PK_Porthcurno https://en.wikipedia.org/wiki/PK_Porthcurno (https://pkporthcurno.com/ https://pkporthcurno.com/) (There's also the https://en.wikipedia.org/wiki/Minack_Theatre 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.)
- kitd 10mo ago
  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.
  - thomasbibby 10mo ago
    There is also a small museum at the site, worth a look if you visit again! https://valentiaisland.ie/cable-station/ https://valentiaisland.ie/cable-station/
- deleted 10mo ago
  [deleted]
neillyons 10mo ago
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!
- dboreham 10mo ago
  Similar history for Denver.
- alexfoo 10mo ago
  > 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/telegraph-history.pdf 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.
  - Aromasin 10mo ago
    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.
    - jillesvangurp 10mo ago
      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.
teleforce 10mo ago
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-undersea-cables/ https://blog.sciencemuseumgroup.org.uk/the-legacy-of-underse... [2] Gutta-percha: https://en.wikipedia.org/wiki/Gutta-percha https://en.wikipedia.org/wiki/Gutta-percha
- daedrdev 10mo ago
  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
andyjohnson0 10mo ago
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 https://en.wikipedia.org/wiki/The_Victorian_Internet
- kogasa240p 10mo ago
  Oh wow will definitely give that book a read, very interesting.
  - eszed 10mo ago
    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.
- jgalt212 10mo ago
  I came here to recommend this fine book as well.
- retrac 10mo ago
  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 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=h&lvl=19 https://www.bing.com/maps/?v=2&cp=42.38148%7E-71.12936&style...
petesergeant 10mo ago
Is the latency the same now as it was for the signal itself? Obviously the throughput is rather different.
- hylaride 10mo ago
  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).
  - joecool1029 10mo ago
    > 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 https://en.wikipedia.org/wiki/Speed_of_electricity
    - hylaride 10mo ago
      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.
      - everfrustrated 10mo ago
        That's the point of hollow-core fibre which is absolutely being used where decreasing latency even by small amounts is worth it.
Alive-in-2025 10mo ago
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/ 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.
pchristensen 10mo ago
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/ https://www.wired.com/1996/12/ffglass/ [2] https://news.ycombinator.com/item?id=46433901 https://news.ycombinator.com/item?id=46433901
- seany 10mo ago
  https://archive.is/rs7Vq https://archive.is/rs7Vq
thijson 10mo ago
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.
nephihaha 10mo ago
The original internet, more or less. Apparently whales liked to scratch themselves on some of the cables though.
jimmySixDOF 10mo ago
... 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-sings-first-transatlantic-telephone-cable https://www.sciencemuseum.org.uk/objects-and-stories/robeson...
KineticLensman 10mo ago
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).
- thenthenthen 10mo ago
  This forced Germans to build some of their own cables, super interesting history: https://blogs.mhs.ox.ac.uk/innovatingincombat/yap-island-german-cable-telegraphy-world-war-one/index.html https://blogs.mhs.ox.ac.uk/innovatingincombat/yap-island-ger...
mjlee 10mo ago
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 https://en.wikipedia.org/wiki/Zimmermann_telegram
alexjf12 10mo ago
here's an interesting series of videos on undersea cables, as described by... Tool Time from Home Improvement https://youtu.be/zmyBSrQodnI?si=OpFZhiQeNn3ax58p https://youtu.be/zmyBSrQodnI?si=OpFZhiQeNn3ax58p
utopiah 10mo ago
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.
hakkikonu 10mo ago
in this context: https://www.submarinecablemap.com/ https://www.submarinecablemap.com/
deleted 10mo ago
[deleted]
girishso 10mo ago
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.
- foxglacier 10mo ago
  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.
- dan-robertson 10mo ago
  ?? The system was completed in 1902. There had already been transatlantic telegraph cables (and I assume others) for many decades.
dan-robertson 10mo ago
Is there a more detailed map of the cables somewhere. The map here and on Wikipedia does not match the OP’s resiliency claims.
Lio 10mo ago
I realise it's this is about the all "Red" line but given Britain's long and close relationship with Portugal and the island of Madeira that the line to India didn't run through there. Aha! OK, after a quick search on Wikipedia I can see that that did in fact happen: https://en.wikipedia.org/wiki/Electrical_telegraphy_in_the_United_Kingdom https://en.wikipedia.org/wiki/Electrical_telegraphy_in_the_U...

228 points by giuliomagnifico 10mo ago

Here is some more information: https://en.wikipedia.org/wiki/All_Red_Line 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 https://en.wikipedia.org/wiki/Pacific_Cable_Station

alexfoo 10mo ago
Anyone visiting the South West of the UK should go visit https://en.wikipedia.org/wiki/PK_Porthcurno https://en.wikipedia.org/wiki/PK_Porthcurno (https://pkporthcurno.com/ https://pkporthcurno.com/) (There's also the https://en.wikipedia.org/wiki/Minack_Theatre 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.)
kitd 10mo ago
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.
- thomasbibby 10mo ago
  There is also a small museum at the site, worth a look if you visit again! https://valentiaisland.ie/cable-station/ https://valentiaisland.ie/cable-station/
deleted 10mo ago
[deleted]

neillyons 10mo ago

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!

dboreham 10mo ago
Similar history for Denver.
alexfoo 10mo ago
> 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/telegraph-history.pdf 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.
- Aromasin 10mo ago
  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.
  - jillesvangurp 10mo ago
    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.

teleforce 10mo ago

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-undersea-cables/ https://blog.sciencemuseumgroup.org.uk/the-legacy-of-underse... [2] Gutta-percha: https://en.wikipedia.org/wiki/Gutta-percha https://en.wikipedia.org/wiki/Gutta-percha

daedrdev 10mo ago
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

andyjohnson0 10mo ago

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 https://en.wikipedia.org/wiki/The_Victorian_Internet

kogasa240p 10mo ago
Oh wow will definitely give that book a read, very interesting.
- eszed 10mo ago
  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.
jgalt212 10mo ago
I came here to recommend this fine book as well.
retrac 10mo ago
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 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=h&lvl=19 https://www.bing.com/maps/?v=2&cp=42.38148%7E-71.12936&style...

petesergeant 10mo ago

Is the latency the same now as it was for the signal itself? Obviously the throughput is rather different.

hylaride 10mo ago
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).
- joecool1029 10mo ago
  > 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 https://en.wikipedia.org/wiki/Speed_of_electricity
  - hylaride 10mo ago
    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.
    - everfrustrated 10mo ago
      That's the point of hollow-core fibre which is absolutely being used where decreasing latency even by small amounts is worth it.

Alive-in-2025 10mo ago

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/ 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.

pchristensen 10mo ago

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/ https://www.wired.com/1996/12/ffglass/ [2] https://news.ycombinator.com/item?id=46433901 https://news.ycombinator.com/item?id=46433901

seany 10mo ago
https://archive.is/rs7Vq https://archive.is/rs7Vq

thijson 10mo ago

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.

nephihaha 10mo ago

The original internet, more or less. Apparently whales liked to scratch themselves on some of the cables though.

jimmySixDOF 10mo ago

... 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-sings-first-transatlantic-telephone-cable https://www.sciencemuseum.org.uk/objects-and-stories/robeson...

KineticLensman 10mo ago

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).

thenthenthen 10mo ago
This forced Germans to build some of their own cables, super interesting history: https://blogs.mhs.ox.ac.uk/innovatingincombat/yap-island-german-cable-telegraphy-world-war-one/index.html https://blogs.mhs.ox.ac.uk/innovatingincombat/yap-island-ger...

mjlee 10mo ago

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 https://en.wikipedia.org/wiki/Zimmermann_telegram

alexjf12 10mo ago

here's an interesting series of videos on undersea cables, as described by... Tool Time from Home Improvement https://youtu.be/zmyBSrQodnI?si=OpFZhiQeNn3ax58p https://youtu.be/zmyBSrQodnI?si=OpFZhiQeNn3ax58p

utopiah 10mo ago

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.

hakkikonu 10mo ago

in this context: https://www.submarinecablemap.com/ https://www.submarinecablemap.com/

deleted 10mo ago

[deleted]

girishso 10mo ago

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.

foxglacier 10mo ago
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.
dan-robertson 10mo ago
?? The system was completed in 1902. There had already been transatlantic telegraph cables (and I assume others) for many decades.

dan-robertson 10mo ago

Is there a more detailed map of the cables somewhere. The map here and on Wikipedia does not match the OP’s resiliency claims.

Lio 10mo ago

I realise it's this is about the all "Red" line but given Britain's long and close relationship with Portugal and the island of Madeira that the line to India didn't run through there. Aha! OK, after a quick search on Wikipedia I can see that that did in fact happen: https://en.wikipedia.org/wiki/Electrical_telegraphy_in_the_United_Kingdom https://en.wikipedia.org/wiki/Electrical_telegraphy_in_the_U...