Ep 31 Transatlantic Telegraph Cable Failure

Engineering News – Improving Electrical Insulation (4:20)

This week's engineering failure is the Transatlantic Telegraph Cable Failure (6:50). We tried not to string the episode out too much. They got off to a rocky start, a little drama, but they eventually turned it around (28:40) and a decade later they had two working cables. And now we can look at cat pictures on the internet at work.

Great Eastern Grappling Hook



Engineering News

Transatlantic Telegraph Cable Failure

Episode Summary

Hi and welcome to Failurology; a podcast about engineering failures. I’m your host, Nicole

And I’m Brian. And we’re both from Calgary, AB.

Before we get into the news, we have an update from a previous news article. The container ship Ever Given has successfully traversed the Suez Canal after getting stuck in the canal in March.

I read that Ever Given was impounded for three months until the ship’s owners and the canal owners could reach a compensation deal after Ever Given blocked the shipping route for 6 days.

This week in engineering news, improved electrical insulation

  • upgrades to electrical insulation that can remove heat more effectively.

  • Hasn't changed much since world war II

  • More stress on the grid, faster processing and using electricity for transportation

  • The heat these systems generate can cause them to fail, but at the same time, we have to protect them from weather

  • University of Texas at Austin and the US Army Research Lab are looking at new materials for insulation and packaging to remove heat more effectively

  • Looking at materials that can

    • Large electrical resistance

    • Tolerance to extreme temperatures

    • Ability to handle mechanical stress

    • Resistance to moisture

    • And good thermal conductivity

  • Nanocomposite materials from polymers with nanoparticles in them that have better thermal performance than metals, but are lightweight, corrode less, and easier to manufacture

  • Applications are endless - power grids, laptops, minimize power plant cooling, electric aviation, etc

Now on to this week’s engineering failure; the Transatlantic Telegraph Cable Failure.

First off, what is a transatlantic telegraph cable and is there a Trans Atlantic Fax cable too?

  • Undersea cables running under the Atlantic for long distance communication.

Cable Info

  • Construction started in the late 1850s.

  • Date of first use was Aug 16, 1858, but it didn't last long

  • Valentia Island, Ireland to Heart’s Content, Newfoundland

  • Design capacity - 8 words per minute (worse than dial up)

  • Owner - Atlantic Telegraph Company

  • Operator - New York, Newfoundland and London Telegraph Company & French Atlantic Cable Company


  • Wildman Whitehouse - medical doctor by training, taken interest in the new electrical tech and decided to follow a new career - no formal training in physics, knowledge gained through practical experience

  • William Thomson - responsible for the law of squares

  • Charles Tilston Bright - chief engineer

  • Cyrus West Field - VP of Atlantic Telegraph Company

Issues to Overcome and Route

  • Waterproofing cable, electricity and water aren’t good together. Used Gutta Percha, a material newly available in Europe from Asia that wasn’t affected by pressure and was waterproof. (a natural thermoplastic rubber that can be molded once heated and will harden when cooled)

  • Many successful Gutta Percha cables were laid across Europe and parts of North America in the 1820’s to 1840’s.

  • Field reaches out to Lieutenant Matthew Maury, the head of the National Observatory in Washington who had coincidentally just completed an oceanographic survey and him and his team had found a plateau that ran across the North Atlantic that could support the proposed Telegraph Line.

  • Western Union, a competitor of Field’s, proposed a route across the Bering Straight from Alaska to Siberia but was severely restricted due to the lack of trees in Siberia to make poles.

Cable Thickness and Retardation

  • Thomson predicted the transmission speed would be very slow due to an effect called retardation

  • Law of squares - transmission line theory

    • Current injected into the line by a step in the voltage reaches a max at a time proportional to the square of the distance down the line.

    • tmax = ½ RCx2

    • Tmax - time at which the current reaches a maximum

    • R - resistance per metre of the line

    • C - capacitance per metre of the line

    • X - distance from the input of the line

  • Whitehouse disagreed - joined several underground lines together to a similar distance of the transatlantic route and said there would be no problem

  • Thomson thought that the underwater cables were not comparable to underground cables - tested similar cable and found resistance up to a factor of two

  • Thomson thought a larger cable was needed to mitigate retardation - Whitehouse disagreed and since the thinner cable was cheaper, that is what they went with


  • Thomson favoured a mid Atlantic start with two ships travelling out to each coast - cut time in half

  • Whitehouse wanted both ships to travel together from Ireland so progress could report back to Valentia through the cable

  • Whitehouse as the Chief Electrician overruled the 1857 voyage - Whitehouse was supposed to be on board the cable-laying vessel but made excuses to avoid - Thomson was sent in his place

  • Bright (chief engineer) convinced the directors to do a mid atlantic route for the 1858 voyage

  • In 1858 Field assigned Thomson and Whitehouse to two different ships to avoid conflict but since Whitehouse never went Thomson went alone.

  • In July 1858, four British and American vessels–the Agamemnon, the Valorous, the Niagara, and the Gorgon–met in mid-ocean for the fifth attempt. On July 29, the Niagara and the Gorgon, with their load of cable, departed for Trinity Bay, Newfoundland, while the Agamemnon and the Valorous embarked for Valentia, Ireland. By August 5, the cable had been successfully laid, stretching nearly 2,000 miles across the Atlantic at a depth often of more than two miles.

  • Europe and North America are linked for the first time, communication is almost instantaneous. Celebratory fireworks catch the bell tower of New York City on fire.

Thomson’s Mirror Galvanometer

  • Thomson wanted a better method of detecting a signal across the cable

  • Developed the mirror galvanometer

    • Ammeter - measure electrical current in a circuit

    • By deflecting a light beam with a mirror

    • Very sensitive instrument

  • Requested money from the board to test his galvanometer and build more - only given ¼ of what he requested and only permission to test out on the next voyage

  • Turns out, it was extremely good at detecting positive and negative edges of telegraph pulses that represented a morse ‘dash’ and ‘dot’ respectively (unlike overland telegraphy, both pulse were the same length)

  • Thomson believed he could test low voltages from regular telegraph equipment - successfully tested it on 4,300 miles of cable in underwater storage in Plymouth - for reference, the cable they were installing was 3,500 km.

  • Whitehouse wanted to use massive high voltage induction coils, producing several thousand volts to create enough current to drive standard electromechanical printing telegraphs used on inland telegraphs

  • Thomson’s instrument had to be read by hand and could not be read

  • Thomson invented the syphon recorder for the second transatlantic attempt in 1866

    • Electromechanical device to receive submarine telegraph cables

  • Although Thomson was merely an advisor, it was not long before all electrical decisions were deferred to him - Whitehouse kept bailing on the voyages

Damaged Cable

  • Whitehouse drove 2,000 voltages through the cable shortly after they finished laying it on Aug 5th and damaged the insulation

  • Press had been told the project was a success

  • Whitehouse said 5 or 6 weeks would be needed for “adjustments”

  • Whitehouse finally gave up on his own equipment and used the mirror galvanometer which worked - but he took those messages and printed them out so it looked like the printing telegraph was working

  • In Sept 1958 after progressive deterioration of the insulation, the cable failed

  • Whitehouse was held responsible and fired - Thomson had to reconstruct what happened

  • Cable was most vulnerable in the first hundred miles from Ireland - not only was it too small, it was also poorly manufactured - they had used a different cable at first and then spliced it into new to continue the installation

  • In some places, the conductor was badly off centre - could easily break through the insulation through mechanical strains during laying

  • Tests were conducted on samples of the submerged cable - when perfect insulated, there was no problem applying thousands of volts - a pinprick hole “lit up like a lantern” when tested and burned a large hole in the insulation

  • 732 messages passed through the cable before it failed and they took about 17hrs to travel from one side to the other

    • Collision between Cunard Line ships Europa and Arabia reported on Aug 17

    • British Government ordered two regiments in Canada to embark for England, saving 50,000 dollars at the time (assuming because they didn’t have to send a ship to deliver the message)

Preparing for a new attempt

  • Took until 1864 to raise enough money to try again - which is honestly surprising that the value wasn’t noticed right away. Was probably difficult to communicate between Europe and North America since, you know, the cable didn’t work.

  • Cables had been submerged in the Mediterranean and Red Sea since the first Transatlantic cable attempt and they learned some things. Here is what the 1864 cable was made of

    • Core consisted of seven twisted strands of very pure copper coated with waterproof insulating compound, then covered with four layers of gutta-percha (a natural thermoplastic rubber that can be molded once heated and will harden when cooled), alternating with four thin layers of compound cement

    • Core was covered with hemp saturated in a preservative solution, helically wound eighteen single strands of high tensile steel wire, covered with fine strands of manila yarn steeped in preservative

    • 980kg/km for entire cable - nearly twice the weight of the old cable

    • Haymills successfully manufactured 48,000km, 1,600 tons, by 250 works over 11 months

Second Cable

  • SS Great Eastern left Valentia fitted for 4,300km of cable on July 15, 1865

  • Aug 2 after 1,968km the cable snapped near the stern of the ship and the end was lost

  • July 13, 1866 Great Eastern started again to lay a new cable and complete the broken one and reached Newfoundland on July 27 - 2 weeks, not bad

  • 9am the next morning, England send the following message “it is a great work, a glory to our age and nation, and the men who have achieved it deserve to be honoured among the benefactors of their race”

  • August 1866 Great Eastern and other ships went in search of the lost cable to splice it to the new

  • A needle in a haystack if there ever was one

  • August 10th, the Albany caught the cable and brought it to the surface - it slipped from the buoy during the night - this happened several more times until Sept 1866 - been on the ocean floor for over a year

  • The recovered cable was spliced into a fresh cable and headed out for Newfoundland where it arrived Sept 7

  • There were now two working telegraph lines

Current Cables

  • The original telegraph cables, of which there were more than just these two, were eventually made obsolete and replaced with telephone and data cables that still exist today.

  • There are an estimated 380 underwater cables in operation today around the world.

  • 1.2 million km long

  • Some are funded by Facebook, Google, Microsoft and Amazon - which is honestly concerning

  • I honestly thought we were using satellites until I started researching this failure

  • Hurricane Sandy knocked out several key exchange links in 2012

  • There are about 200 failures per year

    • Fishing nets

    • Ship anchors

    • Sometimes earthquakes

    • Underwater landslides

  • Use multiple routes so service is rarely interrupted

  • Tapping these cables is even a form of espionage - US did this for a decade during the cold war, but they weren’t the only ones

So there you have it, we tried not to string it out too much, they got off to a rocky start, a little drama, but they eventually turned it around and a decade later they had two working cables. And now we can look at cat pictures on the internet at work.

For photos, sources and an episode summary from this week’s episode head to Failurology.ca. If you’re enjoying what you’re hearing, please rate, review and subscribe to failurology, so more people can find it. If you want to chat with me, my twitter handle is @failurology, you can email me at thefailurologypodcast@gmail.com, or you can connect with me on Linked In. Check out the show notes for links to all of these.

Thanks everyone for listening. And tune in to the next episode where we’ll talk about the Montreal Olympic Stadium, or more commonly called the Big O. This one might take the cake. Bye everyone, talk soon!