To achieve a solid foundation for the bridge, workers excavated the riverbed in massive wooden boxes called caissons. These airtight chambers were pinned to the river’s floor by enormous granite blocks; pressurized air was pumped in to keep water and debris out.
Workers known as “sandhogs”—many of them immigrants earning about $2 a day—used shovels and dynamite to clear away the mud and boulders at the bottom of the river. Each week, the caissons inched closer to the bedrock. When they reached a sufficient depth—44 feet on the Brooklyn side and 78 feet on the Manhattan side—they began laying granite, working their way back up to the surface.
Underwater, the workers in the caisson were uncomfortable—the hot, dense air gave them blinding headaches, itchy skin, bloody noses and slowed heartbeats—but relatively safe. The journey to and from the depths of the East River, however, could be deadly. To get down into the caissons, the sandhogs rode in small iron containers called airlocks. As the airlock descended into the river, it filled with compressed air. This air made it possible to breathe in the caisson and kept the water from seeping in, but it also dissolved a dangerous amount of gas into the workers’ bloodstreams. When the workers resurfaced, the dissolved gases in their blood were quickly released.
This often caused a constellation of painful symptoms known as “caisson disease” or “the bends”: excruciating joint pain, paralysis, convulsions, numbness, speech impediments and, in some cases, death. More than 100 workers suffered from the disease, including Washington Roebling himself, who remained partially paralyzed for the rest of his life. He was forced to watch with a telescope while his wife Emily took charge of the bridge’s construction. Over the years, the bends claimed the lives of several sandhogs, while others died as a result of more conventional construction accidents, such as collapses, fires and explosions.
By the early 20th century, scientists had figured out that if the airlocks traveled to the river’s surface more gradually, slowing the workers’ decompression, the bends could be prevented altogether. In 1909, New York’s legislature passed the nation’s first caisson-safety laws to protect sandhogs digging railway tunnels under the Hudson and East rivers.
Essay about The Brooklyn Bridge
971 Words4 Pages
The Brooklyn Bridge
In the winter of 1852, John Roebling and his 15 year-old son, Washington were riding a ferry boat across the East River from New York to Brooklyn. John Roebling was an engineer. His specialty was building bridges. As he looked across the East River, he could picture the bridge he wanted there. For years after that, John tried to convince people that his plan for a bridge across the East River was a good one. But most people thought it was nearly impossible to bridge the wide and powerful river. John knew it would be difficult. There were many problems to be solved. The bridge would have to be strong enough to withstand the swift currents and powerful winds of the East River. It could not get in the way of…show more content…
Washington shouted a warning but his father couldn't move fast enough. The boat slammed into the pier, John's injury became badly infected and he died of lock jaw, a month later.
John's sudden death was a shock to everyone. Now Washington and his father's dream was in danger, and he was the only one who could keep it alive. Although he was young and inexperienced, he decided he had to carry on the work his father had started. He accepted the job of Chief Engineer of the Brooklyn Bridge. Washington began immediately. He had to build foundations under the water to support the bridge towers. If he built them on the muddy river bottom, they could slip, and the bridge would be unstable. He had to build them on a solid surface. He had to dig down through the mud to reach bedrock. To do this he used enormous caissons. The caissons sat on the river bottom and protected the workers inside as they dug. In 1871, the Brooklyn caisson reached solid bedrock at 44 ½ feet below the river, and the caisson was filled with concrete. The first foundation was finished. On the New York side of the river, the caisson sank deeper and deeper below the river without reaching solid rock. Washington worked day and night doing tests on the soil beneath the caisson. He discovered that it was hard-packed sand and gravel, a very solid surface. He concluded that it could support the bridge tower. The caisson was 78 ½ feet below the river.
Washington spent many hours in the