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Raising a Ladder to the Moon, Under the Sea

Bilbao, Spain | Virginia Beach, Virginia

Today, September 22, 2017, business and government leaders from around the world gather in Virginia Beach to unveil a modern-day marvel on the ocean floor: a 4,000-mile-long cable stretched between North America and Spain that can transmit eight times the volume of the U.S. Library of Congress, in one second. Marea – named for the Spanish word “tide” – is the first subsea cable connecting the United States and Spain. Completed by Microsoft, Facebook, and Telxius, Marea establishes a faster and stronger telecommunications link not only to Europe, but to the next billion internet users that will come from Asia, Africa, and the Middle East.

It took more than five months for engineers and the crew aboard the CS Dependable to load and lay Marea along the seabed, which in spots plunges to depths of more than 17,000 feet. A daunting feat today, but downright unthinkable 150 years ago when American financier Cyrus Field first set out to connect the New World with the old via an undersea wire. News stories at the time deemed his ambitious attempts “only one degree, in the scale of absurdity, below that of raising a ladder to the moon.”[1]

It’s a fitting day to recall not just the enormous engineering innovation that went into this first subsea cable, but the continuing innovations that help make cables like Marea part of the critical infrastructure of our own time.

Few people before Field’s day understood the profound impact that creating a communications link between the world’s continents would have. The War of 1812 between Great Britain and the United States, for instance, would have ended two weeks earlier – preventing 2,792 casualties at the bloody Battle of New Orleans – if news of a truce had reached troops before that battle began.

Map of Marea cable path across Atlantic Ocean
Map of Marea cable path across Atlantic Ocean
Cyrus Field, American financier
Cyrus Field, American financier

The dream of connecting Europe and the United States with a cable was born with electricity, which made possible the invention of telegraphy, the process of transmitting text or symbols through an electric current. While inventors across Europe and the U.S. experimented with battery-powered telegraphs, American inventor Samuel Morse was inspired to develop a binary code of pulses to transmit natural language. He demonstrated his invention in 1837, catching the eye of investor and machinist Alfred Vail, who worked with Morse to patent an electromagnetic telegraph machine that printed messages on a strip of paper.

In 1844, with the help of a $30,000 grant from the U.S. Congress, long-distance telegraphy became a commercial reality when Morse and Vail dispatched the first Morse Code message from the Supreme Court chamber in Washington, D.C. to the B & O Railroad Depot in Baltimore, Maryland: “What hath God wrought?” The Information Age had arrived.

Less than a decade later, countries around the world were laced with extensive telegraph networks. Communications that had taken weeks by horse and carriage now occurred instantaneously. Telegraphy transformed how people communicated and spread news, changing forever how journalists, politicians, bankers and even military leaders conducted their business. By the 1850s, the United States alone had 23,000 thousand miles of land-based cable, Prussia had 1,400 miles, Great Britain 2,200 miles, and France 700 miles. By 1861, the United States was connected coast to coast by cable, bringing the fabled run of the Pony Express to an end.

After conquering overland communications, telecommunications pioneers set their sights on bridging the seas. But underwater telegraphy was plagued by technical barriers, particularly by the inability to protect the wire from water. While inventors in London and New Jersey experimented with methods to keep the cable dry, a solution was found half way across the globe, in the Malaysian archipelago, where the sap from the gutta tree proved an effective thermoplastic insulator.

Samuel Morse, inventor of the Morse code
Samuel Morse, inventor of the Morse code

When warmed, the substance, known as gutta-percha, became pliable and molded around a copper wire. In the deep ocean, the cold water hardened it into a firm shell. By 1851 gutta-percha was imported to the British Isles and used on a 25-mile telegraphic line connecting London to France across the English Channel.

But the experiment failed. The insulation proved too thin, and water seeped into the cable, garbling signals before they reached the end of the line. And within a few hours, the malfunctioning cable was snagged and severed by a curious fisherman off the coast of France.

The following year, in 1852, European engineers tried again, this time protecting the copper cable with a sheath of gutta-percha covered in hemp and incased in an iron fiber skirt. This second cross-channel cable worked, and within five years cables connected England with France, and the Netherlands. Soon Ireland, Corsica, Sardinia, and Italy were connected, and a line ran across the Black Sea speeding up British contact with Crimea during the Crimean War.[2]

Illustration of boat laying cable from Newfoundland, Canada to New York
Illustration of boat laying cable from Newfoundland, Canada to New York

Back in North America, an attempt to wire Newfoundland, Canada to New York was on the verge of bankruptcy. Desperate for an investor to save the project, the designer approached Field, who declined to invest. But the offer got him thinking. What if Newfoundland could be a key junction point in a new transatlantic telegraph? In 1856, he purchased the failing Newfoundland cable company, founded the Atlantic Telegraph Company and staked his fortune and reputation to bring his “outlandish” plan to life.[3]

In 1857, two of Field’s ships set sail in the Atlantic with enough cable to wrap the globe 13 times. Just five miles out to sea, the cable snapped. The ship and crew returned, collected the cable and set out again. This time, they got farther, about 335 miles out to sea, but again the cable snapped, dropping 12,000 feet to the ocean floor. Despite the loss, Field was pleased. The cable had maintained a continuous signal to the point where it had snapped.

Depiction of telegraph message between U.S. President James Buchanan and Queen Victoria
Depiction of telegraph message between U.S. President James Buchanan and Queen Victoria

Finally, on August 16, 1858, a telegraphic line of seven copper wires weighing one ton per nautical mile was successfully laid between the west coast of Ireland and Newfoundland. It was a huge event for people on both sides of the Atlantic. The cable officially opened when Queen Victoria sent U.S. President James Buchanan a message in Morse Code “fervently hoping that the electric cable, which now connects Great Britain with the United States, will prove an additional link between the two places whose friendship is founded upon their common interests and reciprocal esteem.”[4]

Fireworks lit up the New York skyline, accidentally setting city hall on fire. The English response was more officious but nonetheless celebratory, as the chief British engineer on the project, Charles Bright, was given an immediate knighthood, at the age of 26.[5] And Field became an instant hero across the United States, regarded by many as one of the most famous and accomplished individuals of his age.

But the jubilation between the two countries was short-lived when the cable stopped functioning just a few weeks later. Engineers soon learned that they had not yet mastered the science needed to keep a subsea cable of such length functioning properly. Their biggest problem was the degradation or loss of the signal as it traveled such a long distance over a copper wire in deep, cold water. This was a challenge that could be mastered only through the hard experience gained once the first trans-Atlantic cable was successfully laid.

The public, however, was less understanding. Celebration turned to condemnation of the venture and Field’s leadership of it, and Congressional investigations and legal threats soon followed. Some thought that the entire venture had been a fraud or a hoax. Field found that where well-wishers previously had stopped him on the sidewalk to congratulate him, now even his friends crossed the street to avoid saying hello. The U.S. Civil War intervened, efforts to repair the line were put on hold for several years, and the public understandably turned its attention elsewhere.

Fireworks lit up the New York skyline, accidentally setting
city hall on fire.

Illustration of boat laying transatlantic telegraph cable

Once the Civil War ended, however, engineering efforts resumed. Field had never given up on his dream, and the necessary technology had advanced considerably in the intervening years. While initial efforts in 1865 failed when a ship lost the end of a cable, the following summer, in 1866, Field’s crew returned to the sea and met with success. When the ship returned, it came “gliding calmly in as if she had done nothing remarkable, dropped her anchor in front of the telegraph house, having trailed behind her a chain of two thousand miles, to bind the old world to the new.”[6]

From the telegraph house of Heart’s Content, Newfoundland, Field sent a telegram to New York, “We arrived here at 9 o’clock this morning. All well. Thank God, the cable is laid and in perfect working order.”

Hailed as the “eighth wonder of the world,” the cables created a network of almost instantaneous communications and proved to be an early catalyst of globalization. News that previously took weeks or months to reach its destination could be relayed within hours. As technology and cable-laying techniques continued to advance, the submarine cable network expanded, and by the early 20th century much of the world was connected by a network of cables.

In 2017, people might look back at Field and conclude that subsea cables are “old” technologies whose advances ended long ago. They might even think that, in an age of ubiquitous wireless communication, the role of such cables is a vestige of the past. But both views would be mistaken.

The technology of subsea cables has continued to advance in new and important ways.

Artist interpretation of the transatlantic telegraph cable

One of the big leaps came in 1988, as the internet was in its infancy. A new generation of engineers laid the first transoceanic fiber-optic cable, linking the United States, the United Kingdom, and France. These new cables transmit information by light over glass or plastic strands that have the same diameter as human hair. They enable data transmissions at higher bandwidths than copper cables, and signals suffer less loss over distance.

A cable with fiber optic strands bundled together represented a huge advance in the ability to move information around the planet. This became a critical ingredient of what made the internet as we now know it possible. Today more than 99 percent of international communications is routed through fiber optic cables, with much of it at the bottom of the world’s oceans.[8]

All of this points in part to the human elements of technology, both in terms of its use and its continuing advances. Cloud computing and artificial intelligence are reshaping not only the usage of the internet, but its role in society.

The Marea cable on beach

Take something like video content on the internet. What some thought was mostly about YouTube videos a few years ago is now about a whole lot more. The future of healthcare involves telemedicine and high-quality video connections.

The future of education often now involves high-quality distance learning, either with real-time video connections or on-demand streaming. The future of business and job growth often involves companies based in one state or country opening an office or factory in another – and communicating in real time. The MAREA cable itself will play a role, for example, in enabling Sanjo, a tools company headquartered in Barcelona, to open a factory and employ people in Virginia Beach.

Given all of this, it’s perhaps no surprise that Cisco estimates that by next year one million minutes of video content will move across the internet every sixty seconds.[9] Broadband connectivity has become a necessity of life. It helps explain why Microsoft has invested to build one of the largest data center campuses in the world in Boydton, Virginia, where we meet the increasing cloud needs of businesses and consumers alike with services that range from enterprises using Azure and Office 365 to consumers connecting on Skype, Xbox Live, and so much more. It also explains why we feel so strongly about causes like closing the broadband gap for the 23.4 million Americans who live in rural counties that lack this connectivity.

This also helps explain why Marea’s added subsea cable capacity across the Atlantic comes at a critical time. Submarine cables already carry 55 percent more data across the Atlantic than trans-Pacific routes and 40 percent more data than between the U.S. and Latin America. Without question the demand for even more data flows across the Atlantic will keep growing.

Marea cable construction on beach, Bilbao, Spain
Marea cable construction on beach, Bilbao, Spain

The human dimension is not only important in the need for more subsea cables, but in the work needed to put them in place. A venture like Marea takes more than a village, with work required in multiple countries.

This work started with great engineering. Marea builds on many prior advances and takes them farther than ever before. For example, it takes a new step in addressing the technology challenge that has plagued every subsea cable since the time of Cyrus Field, namely the degradation of a signal over a long distance under deep and cold water. With Marea, engineers at Microsoft, Facebook, and Telxius, working with experts at cable suppliers, redesigned the workings of underwater repeater stations to reduce this decibel loss even more for the light traveling through fiber optic cables. And the three companies invested in innovative on-shore electrical supplies that will power the repeater stations across the Atlantic, enabling the use of eight fiber optic pairs rather than the usual six. In short, it added two more lanes to the information super highway.

Like so many infrastructure investments, Marea required important collaboration between the private and public sectors. Authorities in the Spanish Government played an important role in facilitating the application for the installation permit for the cable landing in the Bilbao region, which was issued after approval by multiple ministries of the national government with strong support from the region. Similarly, the U.S. landing required approval by four distinct parts of the federal government in Washington, D.C., with the active involvement of local and state authorities in Virginia itself. These steps easily could have required many years. Thanks to strong communication and collaboration, government processes that began in 2015 have led to a finished cable just two years later.

Boat laying Marea cable in Atlantic Ocean
Boat laying Marea cable in Atlantic Ocean

This strong partnership made it possible for the CS Dependable to start laying the cable this year. At an average depth of 5,000 meters, the ship had to lower Marea’s cable to a greater depth than Mount Rainier, near Seattle, is tall. After taking 90 days to load the massive cable on deck, the ship completed its work after 62 days at sea.

While all this involved a feat of modern engineering, some things never change, even over 150 years. Dependable had a crew of 60, representing five countries. And, a good crew needs to eat well.

It’s therefore perhaps not a surprise that the laying of the Marea cable involved not only the latest in fiber optic cable and repeater stations, but also 11,000 meals.

This too required a variety of supplies – including 632 jars of peanut butter.

As today illustrates, subsea innovation and technology have marched forward with continuing advances over a century-and-a-half. Usually on a full stomach.

This too required a variety of supplies – including 632
jars of peanut butter.

Today in Technology is a series that highlights important technology developments from the past and discusses the insights they offer for the tech trends and issues of our own day.

[1] Simone M. Müller, Wiring the World: The Social and Cultural Creation of Global Telegraph Networks (New York: Columbia University Press, 2016), 38.

[2] Arthur C. Clarke, Voice Across the Sea (New York: HarperCollins, 1975), 25.

[3] John Steele Gordon, A Thread Across the Ocean: The Heroic Story of the Transatlantic Cable, (New York: Walker & Company, 2002), 20.

[4] Duncan Geere, “How the First Cable Was Laid across the Atlantic,” WIRED UK, accessed September 22, 2017,

[5] Clarke, Voice Across the Sea, 25.

[6] Ibid.

[7] Ibid.



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