Submarine Networks: An Evolutionary Change – Part 2
As published in the September Issue of SubTel Forum Magazine
By Derek Cassidy
September 20, 2022
Coding across the telegraph networks, even though in its infancy was also seeing a change. In Hamburg, 1848, Friedrich Clemens Gerke studied Morse Code and manipulating it he had made it easier to understand. His innovation or interpretation of the original Morse code was called the Hamburg Telegraph. In 1851 at an International Telegraph Conference the Gerke version of the Morse code was adopted internationally, while the US and Canada still used the American Morse Code version (Samuel Morse version). However, in 1865 the International Telegraph Union, which was established in Paris that year, adopted a new version of Morse code that was a variant of Gerke’s original version. This new ITU code is the Morse code heard and transmitted today, however the American Morse Code is still used by some licenced training schools in America.
From 1851 to 1865 the second variant of Morse Code or Hamburg Code was widely used across Europe and the Far East and in 1865 it changed again to become the final version that would be used. However, this version was not used on the 1866 cable as the original Morse code was still the official code used in the Americas. Even though the Hamburg code and the new ITU-T Code (introduced in 1865) was the officially used versions, many operators used the code that they were familiar with unless they were asked to change the cypher. Technically the telegraph used a common transmission coding language to connect the different cities, markets and industries across the continents.
The technologies surrounding telegraph transmission across oceans and seas was constantly hitting the barrier or wall and this wall was called impedance or signal attenuation attributed to the length of the cable. The 1858 cable nearly succeeded in overcoming this barrier but it was not until the determination of Cyrus Field, William Thompson and many other Heroes of the Telegraph era that this wall was finally breached. It was not only signal loss that was overcome, but new technological advancements allowing for long distance telegraph transmission were made possible. The constant research and development in cable design would also have very serious, mostly positive effects on society, financial and stock markets as well as international communications on a military, government and society level. The 1866 trans-Atlantic Telegraph Cable heralded a new chapter in telegraphy which meant that the developments in new technology that made the 1866 cable possible would affect society as a whole.
Friday, July 27th, 1866, was just like any other normal day, the trans-Atlantic telegraph cable had just been laid and the first telegraph message, across the cable, from Heart’s Content to Valentia Island had just been sent. However, it did set of a chain of events that would eventually lead to the expansion of telegraph communications across the globe. It was not the fact that this trans-Atlantic cable had been successfully laid, for the 1858 trans-Atlantic cable, the third such attempt had also been successfully laid, although it only operated for less than a month before it completely failed. It was the technological advances that had taken place between 1858 and 1866 that enabled such a great leap towards success. We all know that the 1858 cable failed due to the high electrical charge that
Whitehouse insisted on being transmitted across the cable, along with the failure to properly store the trans-Atlantic cable between the 2nd failed attempt in September 1857 and the start of the 1858 expedition. These two factors would lead to major changes and studies into how telegraph, telephone (COAX) and Optical Cable would be stored in the future. William Thompson, who had researched and eventually patented the mirror galvanometer, was able to prove that the electrical current being sent across telegraph submarine cables could be detected at the receiving end by the use of a suspended mirror and influenced by electrical magnetism could reproduce the electrical signals as light on a receiving plane, no matter how faint they were.
With the 1866 trans-Atlantic cable was landed, connected and tested for continuity there was an agreement that the expedition team would set out towards the spot where the 1865 cable was lost 600 miles to the east on the ocean floor.
The recovery of the 1865 submarine telegraph cable was already agreed by Cyrus Field and the Anglo-American Telegraph Company. Hamilton was first officer onboard the SS Great Eastern and had laid the 1865 cable. He was a meticulous person who had charted, plotted and noted the last known position of the 1865 cable, on the seafloor, within a couple of kilometers. He was tasked with this recovery project, on top of his already stressful project to lay the 1866 cable between Valentia Island and Heart’s Content. As Hamilton had already noted and charted the laying of the 1865 cable, the failure location and depth he was in the best position to lead with this expedition. The rest of the expedition had already agreed that Hamilton’s approach to the recovery of the cable was the best possible solution to a very serious problem. The combined lifting capability of the SS great Eastern along with three other ships that would help to spread the weight of the cable that lay on the seabed more than twelve thousand feet below, would be the procedure to be followed. Lifting the cable alone would have been near impossible for the SS Great Eastern, but with added help, all four ships would work in unison to successfully recover the cable. The overall engineering process involved in laying and recovering deep-sea submarine telegraph cables was still in the learning and discovery phase but with the experience already gained so far and with the added successful completion of the 1866 telegraph submarine cable, the recovery did not look that impossible.
First Officer Halpin, on the SS Great Eastern had kept charts and recorded of where the 1865 cable had been lost the previous year and had also made sure that the 1866 cable would be laid on the seafloor at least 200 miles south of the 1865 cable route. This was to make sure that he would have a better chance of recovering the 1865 cable without fowling the 1866 cable. On the 1st August the SS Albany and HMS Terrible both left Trinity Bay and headed out towards the spot where the 1865 cable was lost and then on the 9th August, after getting fresh supplies and refueling, the SS Great Eastern and SS Medway set out to join up with HMS Terrible and SS Albany. They arrived on the site recorded a year earlier and after three weeks and 30 attempts to grapple the cable from the depth they succeeded in getting a successful grapple of the 1865 cable. The recovery process started with multiple grapples runs between all four vessels and when grappled they lifted and then suspended the cable off the seabed. Each in turn, Terrible, Albany, Medway and the Great Eastern lifted the cable slowly so as not to create a situation where the weight was too heavy for one or more vessels and a capsize to happen. On the 1st September the cable was successfully lifted to the surface and the cable end was then officially transferred to the Great Eastern. On the morning of the 2nd September the 1865 cable was now spliced to spare cable 1866 telegraph cable on board and after making calculations and arrangements the fleet set out to Heart’s Content for the second time laying the spare 1866 cable on a route to Heart’s Content, now connected to the 1865 cable and transmitting test telegraph messages to Valentia Island to make sure continuity was good. On the 7th September the 1865 trans-Atlantic cable was landed at Heart’s content and soon afterwards transmission to Valentia was now being done over two cables.
This act of cable recovery was the first such attempt in deep water. Notwithstanding that Charles Bright lead an expedition in 1857 to the recover the 330 miles of telegraph cable that was lost after the first attempt from Whitestrand, Caherciveen. Bright’s successful recovery of the cable along with re-engineering of the cable paying out equipment led to design changes and increased knowledge of cable recovery and repair. It was these advancements made in 1857 which were directly attributable to the short-lived success of the 1858 cable and the recovery of the 1865 cable.
The 1866 trans-Atlantic Telegraph cable, once completed, had shown that with the right engineering technologies the oceanic barrier to telegraph transmission had been overcome. The development of two more long distance telegraph submarine cables was put in motion.
The first of these was the successful completion of the French cable to Newfoundland. The success of the 1866 trans-Atlantic submarine telegraph cable immediately set in motion the project to deliver the France to America cable that was delivered in 1869, by the French Company La Société du Câble Transatlantique Française. This cable went from Brest to St. Pierre in Newfoundland and then on to Cape Cod, Massachusetts and it was laid by the SS Great Eastern. This cable was called the French Atlantic Telegraph Cable and it was a successful one. The issues and problems that the original trans-Atlantic telegraph cables in 1857-58 and 1865-66 encountered were overcome by solutions that were found by Charles Bright, C.F. Varley and William Thompson with regards to cable laying, breaking, the electrical current and power needed to feed the telegraph cable with its many messages and new improvements in words per minute were also achieved. The age of trans-Atlantic telegraphy had arrived, and many new cables were planed and laid across the ocean connecting Europe and America. New cable stations were also required for these new cables as they were not all operated by the same company. In 1873 the Anglo-American Telegraph Company took over the French telegraph company La Société du Câble Transatlantique Française and a new interconnecting cable was laid between Heart’s Content and St Pierre to create a loop on the Canadian side of the Atlantic.
This cable was slightly longer than the 1866 trans-Atlantic cable, but the technology and engineering used was a direct result of the successful 1866 cable. Technology, cable design and engineering were advancing all the time, and this could be seen in the next big step in the march to cross the oceans with telegraph submarine connectivity.
Charles Bright was created the Chief Engineer for the new submarine telegraph cable that would connect Britain with India. For a long time, the telegraph connection between Britain and India was troublesome as it took an overland route across Europe and Asia to reach its final destination. Telegraph messages of all kinds could not be relied on to be fully delivered due to the unsecure path the cables took. However, with the advancement of long-distance telegraph transmission being successfully proven by the three previous cables; 1865, 1866 and 1869 trans-Atlantic Cables the engineering and technology was now available to finally lay a new submarine telegraph cable between Britain and India.
In December 1866 the Telegraph Construction and Maintenance Company, under the guidance of John Pender who went on to become known as the “Cable King”, a proposal was made to the Secretary of State for India that a new cable be laid from England to India. Using the vessel that laid the 1866 submarine telegraph cable, the SS Great Eastern, to lay the bulk of the cable from Bombay (Mumbai) to Aden. From Aden a new cable would be laid up the Red Sea to the Suez Canal and then from here, across Egypt to the Mediterranean and then onto Malta. The next leg would be from Malta to Gibraltar and then to Carcavelos and the final leg to Porthcurno. However, the British Government said that this was not seen as a necessary need as the overland telegraph cable was operational, however not efficiently. So, in 1868 John Pender decided to set up submarine telegraph companies to complete the submarine cable system as a private system. The route was selected and the SS Great Eastern was the ship that would do the cable lay and so the project was inaugurated on the 6th November 1869 when the SS Great Eastern left Portland Docks with the new India cable, she was supported by three other ships, Hibernia, Hawke and Chiltern. Portland is still used today as the main depot for submarine cable storage in Great Britain and is operated by Global Marine Services Ltd.
Robert Halpin, who was First Officer on the SS Great Eastern during the 1865 and 1866 trans-Atlantic cable expeditions and who masterminded the recovery of the 1865 cable from the depths of the Atlantic Ocean, was now Captain of the Great Eastern. His experience was to show when he successfully completed the lay of the French Atlantic cable in August 1869. He was now again in the middle of a new expedition that was going to test the ideas of submarine telegraphy to the limits. The new India cable or Red Sea cable as it was sometimes called would have an approximate length of over six thousand miles and its Bombay (Mumbai) to Aden section was longer than the trans-Atlantic cable of 1865 or 1866. Which would only have been possible because of the engineering success of the 1866 trans-Atlantic cable.
The India cable was successfully landed in Porthcurno on the 6th June 1870 and was the first cable to land here. The India cable had a total of eight cable landing sites and each site was a telegraph cable station and repeater station. The last cable landing site was Porthcurno, which was the terminal for the India cable, and it became just as important as Valentia as a submarine telegraph cable station and was the principal telegraph landing point in Great Britain for trans-Atlantic and other long distance submarine telegraph cables, second only to Valentia Island in Ireland.
The 1866 trans-Atlantic cable in effect had led directly to the development of two more long distance submarine telegraph cables. However, it must be noted that the shore end design of the 1865 trans-Atlantic cable, even though has proven not to a be good one as it allows for anchors and other heavy fishing gear to get tangled up with it, was also used on the 1869 French trans-Atlantic cable and the 1870 Britain to India cable. As technology and engineering design had made such vast advancements it still needed more research into how to fully protect a submarine cable from damage caused by entanglements and hits by fishing gear and anchors.
The other major change that these long-distance submarine telegraphs cables were seen within the monetary and stock markets. The impact was enormous so much so that it had a direct effect on the financial, stock & commodities markets of London, Paris and New York and even as far afield as the Far East and other economic giants. Being able to connect all these markets with a telegraph web of connectivity helped to nurture the markets in international trade and development. Instead of trading with the Americas and relying on communications that would take weeks to be delivered and then more weeks for the answer to be received the ability to communicate and get an answer within a matter of hours was a development factor that pushed the markets into an era of advancement. However, 1866 was a year were there was economic turmoil and the possibility of recession, the injection or positivity that the 1866 trans-Atlantic Telegraph cable put into the economies across the globe was measurable and soon the economical woes of 1866 gave way to the economic revival of 1867.
Another great change was the development of fast international communication and Government Foreign Policy. In the case of Britain, having colonial dependencies across the world meant that communications were very important, which meant a reliable fast communication system was needed and urgently. Great Britain, being the largest colonial power in the 19th century reluctantly saw telegraphy, although expensive, as a fast means to communicate across the empire. However, there were instances where the telegraph could not be used such as connectivity to Canada, India and Australia. All three dependencies either had no direct connection with Great Britain or had a telegraph connection that was open to abuse, sabotage or even eaves dropping as it did not follow a path across British controlled lands.
But the 1866 and 1870 cables overcame these obstacles and soon the development of a new telegraph system to incorporate Australia was now seen that ever more possible. These developments in long distance telegraph communications also meant that Governors and Counsellor staff in Embassies across the Globe saw their personal power wane. Before the development of long-distance telegraph communication, Governors, Councillor & Embassy Staff along with Government Representatives and Agencies had a certain amount of power dealing with the different colonial dependencies due to the fact that Telegraph connectivity was very poor or non-existent. As a lot of decisions needed to be made quiet urgently, the local Governors or Embassy Staff would make these decisions and then formally report back to the Foreign Office or Military HQ with their decision as a delay waiting on a reply could be detrimental to the on-going issue. However, as soon as long-distance telegraph communication was made available their decision-making power was taken away from them as they could get the required answers within the day rather than wait weeks. This was seen as the Foreign Office power struggle that centralised decision making, but it also made it more efficient and introduced the common foreign policy. Other changes that were made were directly related to military planning and decision making. With fast and reliable telegraph communication between the crown dependencies & colonies the military machine could keep in constant contact with local HQ and the military decision makers in Britain.
The success and engineering developments of long-distance telegraph transmission especially with the first four cables of the late 1860s and the India and other Atlantis cables, the SS Great Eastern proved to be a worthy vessel and great asset to the development and deployment of telegraph connectivity across the globe. The ship worked in the four corners of the globe under the stewardship of now Captain Halpin who had gained so much knowledge and experience delivering so many telegraph submarine cables.
The submarine cable design would undergo some change in the 1800s. The single stranded armouring would soon be the mainstay of submarine cables and only increased in diameter depending on location and would be a common development over the multi-stranded armouring as used on the 1857/8 and 1865/69 and India submarine cables. It was soon acknowledged that the single armouring wire was better and also lighter compared to the multi-stranded type and also offered better protection against fishing gear fowling. Soon technology advances allowed for the increased word count and transmission capability that could be transmitted across long distance telegraph submarine cables.
Another great advancement in submarine cable engineering was the ability to localise a submerged fault on a cable. This was put to great use by James Graves, from Valentia Island, who would go on and become the Superintendent of Valentia for 44 years. Graves was working on the 1865 cable, transmitting to the Great Eastern and receiving massages from her though the cable until that fateful day in August when the cable broke. However, instead of just giving up, Graves carried out many experiments on the cable testing the cable impedance and also receiving strange electrical perturbances which he needed to investigate. He wrote and published many papers on his experiments along with many others including C.F. Varley. Charged with this knowledge of submarine telegraphy and electrical charge across the cable he successfully put it to good use when the 1866 trans-Atlantic telegraph cable stopped working in 1872 and it suffered three different breaks which were all recorded, and the location identified by Graves. The 1865 cable lasted until 1877 when it too failed and the locations recorded. The two cables, the original successful trans-Atlantic telegraph cables that made the world of submarine telegraphy happen, were never repaired, but the 1866 cable did get a new lease of life when the Heart’s Content end was taken up and then laid from St Pierre to Bay Roberts to add in extra capacity to link up with the French Atlantic cable. This happened in 1880 and this cable was successful until it failed in 1949.
So not only where the long-distance telegraph cables used for telegraph transmission, it is with their insitu location that they were ideal subjects to research and investigate so that new developments in submarine cable engineering could be advanced.
About the Author
Derek Cassidy is doing a PhD in the field of Optical Engineering; Self-Written and Polymer Waveguide creation and Wavelength manipulation with UCD, Dublin. He is a Chartered Engineer with the IET and Past-Chair of IET Ireland. He is Chairman of the Irish Communications Research Group. He is also currently researching the Communication History of Ireland. He is a member of SPIE, OSA, IEEE and Engineers Ireland. He has patents in the area of Mechanical Engineering and author of over 30 papers on Optical Engineering. He has been working in the telecommunications industry for over 29 years managing submarine networks and technical lead on optical projects. Derek holds the following Degrees: BSc (Physics/Optical Engineering), BSc (Engineering Design), BEng (Structural/Mechanical Engineering), MEng (Structural, Mechanical, and Forensic Engineering) and MSc (Optical Engineering).