Focused as he was on surveying, the engineer should have paid more attention to his surroundings. The year was 1869. Civil engineer John Roebling had begun the site work two years ago, almost to the day. Now just a few more compass readings, across the East River. Soon, work would begin on the longest steel suspension span in the world. A bridge connecting the New York boroughs of Brooklyn and Manhattan.
Roebling was working on the pier with his 32-year old son Washington, also a civil engineer. As the ferry came alongside, the elder Roebling’s toes were caught and crushed so badly, as to require amputation.
“Lockjaw” is such a sterile term, it doesn’t begin to describe the condition known as Tetanus. In the early stages, the anaerobic bacterium Clostridium Tetani produces tetanospasmin, a neurotoxin producing mild spasms in the jaw muscles. As the disease progresses, sudden and involuntary contractions affect skeletal muscle groups, becoming so powerful that bones are literally fractured as the muscles tear themselves apart. These were the last days of John Roebling, the bridge engineer who would not live to see his most famous work.
The German-born civil engineer was the first casualty of the project. He would not be the last.
Washington took over the project, beginning construction on January 3, 1870.
Enormous yellow pine boxes called “caissons” were built on the Brooklyn and New York sides of the river, descending at the rate of 6-inches per week in search of bedrock. Like giant diving bells, the New York side ended up at 78- feet below mean high tide, the Brooklyn side 44-feet. Pressurized air was pumped into these caissons, keeping water and mud at bay as workers excavated the bottom.
In 1872, these “sandhogs” began to experience a strange illness that came to be called “caisson disease”.
Civil War era submarine designer Julius Hermann Kroehl may have recognized what was happening, but Kroehl was five years in his grave by this time, victim of the same “fever”.
Today we call it “the bends”. Pop the top off a soda bottle and you’ll see the principle at work. Without sufficient decompression time, dissolved gasses come out of solution and the blood turns to foam. Bubbles form in or migrate to any part of the body, resulting in symptoms ranging from joint pain and skin rashes, to paralysis and death. The younger Roebling was badly injured as a result of the bends in 1872, leaving him partially paralyzed and bedridden, incapable of supervising construction on-site.
Roebling moved to an apartment in Brooklyn Heights and conducted the entire project looking out the window, designing and redesigning details while his wife, Emily Warren Roebling, became the critical connection between her husband and the job site.
To aid in the work, Emily Roebling took a crash course in bridge engineering. For 11 years she studied higher mathematics, catenary curves, materials strength and the intricacies of cable construction, all while acting as the pivot point on the largest bridge construction project on the planet and nursemaid, to a desperately sick husband.
Historian David McCullough wrote in his book, The Great Bridge: The Epic Story of the Building of the Brooklyn Bridge: “By and by it was common gossip that hers was the great mind behind the great work and that this, the most monumental engineering triumph of the age, was actually the doing of a woman, which as a general proposition was taken in some quarters to be both preposterous and calamitous. In truth, she had by then a thorough grasp of the engineering involved”.
Unlikely as it sounds, fires broke out at the bottom of the river on several occasions, started by workmen’s candles, fed by the oakum used for caulking and turbocharged by all that pressurized air. On at least one occasion, the caisson was filled with millions of gallons of water, before the fire went out for good.
A footbridge connected the two sides in 1877, and soon the wires began to be strung. Wooden “buggies” carried men back and forth along wires suspended hundreds of feet above the water, as individual wires were woven into the four great cables that support the bridge. The work was exacting, with each wire bound together to precise specifications. Rumors about corruption and sleaze surrounded the project when J. Lloyd Haigh, the wire contractor, was discovered to be supplying inferior material. It was way too late to do anything about it, and 150 extra wires were bundled into each cable to compensate. The tactic worked. Haigh’s shoddy wire remains there, to this day.
At the time it was built, the span across the East river linking Brooklyn with Manhattan was the longest suspension bridge in the world.
Construction was completed in 1883, the bridge opening for use on May 24. Emily Roebling was the first to cross, in a carriage, carrying a rooster as the sign, of victory. New York politician Abram Stevens Hewitt honored her, at that day’s dedication. Today a bronze plaque bears name of the first female field engineer.
“…an everlasting monument to the sacrificing devotion of a woman and of her capacity for that higher education from which she has been too long disbarred.’New York politician Abram Stevens Hewitt
Six days later, a rumor started that the bridge was about to collapse. At least 12 people were killed in the resulting stampede. A year later, a publicity stunt by P. T. Barnum helped to put people’s minds at ease when Jumbo, the circus’ prize elephant, led a parade of 20 other elephants across the bridge.
For a long time the span was called the “New York and Brooklyn Bridge” or the “East River Bridge”, officially becoming the “Brooklyn Bridge” only in 1915. At least 27 were killed in its construction. Three from the bends, several from cable stringing accidents and others crushed under granite blocks or killed in high falls.
Even today, popular culture abounds with stories of suckers “buying” the Brooklyn Bridge. It was the longest bridge in the world for its time, and would remain so until 1903. Roebling had designed his project to be six times the strength required for the job. Even with those defective cables, the bridge is four times as strong as it needs to be. Many of the Brooklyn Bridge’s contemporary structures have long since gone. Johann Augustus Roebling’s bridge carries 145,000 cars, every day.