On a summer afternoon in 1869, John Augustus Roebling stood on a Brooklyn pier taking sightings for the greatest bridge ever attempted, when an incoming ferry crushed his foot against the pilings. His toes were amputated; he refused conventional treatment in favour of water therapy; and within a month the German-born engineer was dead of tetanus, before a single stone of his masterpiece had been laid. The Brooklyn Bridge, which he had designed to join Brooklyn and Manhattan across the East River, would be built by his family instead — and it would very nearly destroy them too.
Roebling was already America's foremost builder of suspension bridges, and a manufacturer of the wire rope that made them possible. His plan for the East River crossing was audacious: a main span of nearly 1,600 feet, half as long again as anything then standing, hung from cables of steel wire — the first great use of steel, rather than iron, in a suspension bridge. When he died, his son Washington Roebling, a 32-year-old Civil War veteran who had studied caisson foundations in Europe, took over as chief engineer.
Down in the caissons
The towers had to rest on something solid beneath a tidal river, and the solution was the caisson: a giant upside-down wooden box, sunk to the riverbed, with compressed air pumped in to hold back the water while men dug away the muck beneath by lamplight. As the digging went on, the towers were built on top, pressing the caisson slowly downward. It was hellish work — hot, dim, deafening — and it carried a mysterious price. Men who left the pressurised chamber too quickly were struck by agonising joint pain, paralysis and sometimes death. The workers called it the bends, after the contorted posture of its victims; the bridge's own physician, Andrew Smith, coined the term caisson disease. We now know the cause: nitrogen dissolved in the blood under pressure forms bubbles when the pressure drops too fast, like a fizzing bottle uncorked. The remedy — slow, staged decompression — was not yet understood.
The Brooklyn caisson was stopped in solid hardpan well above bedrock, but on the Manhattan side the diggers had to go far deeper, and cases multiplied. Washington Roebling, who insisted on going down with his men, was carried out collapsed in 1872 and never recovered. Partially paralysed, in chronic pain, his sight and voice failing, he directed the remaining eleven years of construction from a window in Brooklyn Heights, watching the towers rise through field glasses. Fearing the deep Manhattan caisson would kill more men, he made a nerve-racking call: he halted the descent short of bedrock, leaving the tower resting on hard-packed sand. It has not shifted since.
The chief engineer's wife
Between the invalid engineer and the work site stood Emily Warren Roebling. What began as carrying messages became something far greater: she taught herself the mathematics of catenary curves, cable construction and materials strength, negotiated with contractors and politicians, and for years was the de facto voice of the chief engineer on site — so much so that many assumed she was secretly running the project. When trustees moved to dismiss her husband, she lobbied and won. There were other crises: in 1878 the contractor J. Lloyd Haigh was found to have supplied brittle, rejected wire that could not be removed from the cables. Roebling's answer was characteristically cold-blooded — he had built in a safety margin of roughly six times the required strength, and simply ordered extra strands added.
The bridge opened on 24 May 1883, fourteen years after John Roebling's death. Emily rode across first in a carriage, carrying a rooster as a symbol of victory; President Chester A. Arthur walked the span. It was then the longest suspension bridge on Earth, its twin Gothic-arched granite towers looming over every building in New York. The triumph had cost at least twenty lives by conservative counts — some tallies run higher — including the designer himself. Six days after the opening, a rumour that the bridge was collapsing set off a stampede in which twelve people were crushed to death. The following year the showman P. T. Barnum answered lingering doubts in his own style, parading 21 elephants, led by the famous Jumbo, across the span to prove its strength.
Washington Roebling never attended the opening; he watched the fireworks from his window. He lived another four decades, and Emily, who later earned a law certificate, is now honoured on a plaque on the bridge alongside her husband and father-in-law — one structure, three Roeblings. The bridge they paid for so dearly still carries more than a hundred thousand crossings a day, its sand-borne Manhattan tower standing exactly where a broken man decided to stop digging.
Quiz nuggets
- John A. Roebling died of tetanus in 1869, after a ferry crushed his foot before construction began.
- Caisson disease — the bends — is caused by nitrogen bubbles forming in the blood during rapid decompression; the term was coined by bridge physician Andrew Smith.
- Washington Roebling, paralysed in 1872, directed construction for eleven years through field glasses from Brooklyn Heights.
- Emily Warren Roebling crossed first at the opening on 24 May 1883, carrying a rooster for good luck.
- In 1884 P. T. Barnum led 21 elephants, including Jumbo, across the bridge to demonstrate its strength.