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Washington Roebling's drawing of a caisson, 1869
The Politics of BuildingPrior to building the bridge, people traveled from Brooklyn to Manhattan via the South Ferry which opened in 1835. This ferry service was followed in 1849 by the addition of the Wall Street Ferry, the Roosevelt Ferry, and the 23rd Street Ferry. However, the ferry services did not fully service the rapidly growing needs of the Brooklyn population, which rose from 266,000 in 1860 to 396, 000 by 1870: nearly a 50% increase in a decade. Brooklyn was the fastest growing city in the country which prompted the New York Legislature, in 1867, to debate the merits of building a bridge to cross the East River and permanently connect Brooklyn and Manhattan.
Brooklyn Bridge, May 1883 In 1866 the New York State Legislature passed a bill for the bridge construction and hired John Augustus Roebling as “Chief Engineer” at an annual salary of $8,000. Roebling designed a bridge that would meld together art and function. Ulysses S. Grant, U.S. President, also signed a bill in 1869 which approved federal funding for the Brooklyn Bridge plan. This allowed construction on the bridge to commence on the 2nd of January 1870 with site clearing and preparation.
There were a great many people who worked to construct the Brooklyn Bridge, and it is important to pay tribute to those individuals because without their contribution the project could never have been completed. The building of the Brooklyn Bridge was not without a number of catastrophies. Most famously is the bad fortune that befell the Roebling men, namely with John Augustus’ death and the debilitating illness contracted by his son Washington. However, there were almost 30 other deaths associated with the bridge construction. The New York Bridge Company was an organization contracted to build the Brooklyn Bridge. In 1870 digging began for the first tower using the Brooklyn Caisson which contained two water shafts, two man shafts, two supply shafts, and pipes for gas, air and water. The first caisson was launched from the Greepoint shipyard in March, 1870.
Structural Components of the BridgeUnderwater BuildingOnce underwater the engineers utilized a number of means of underground excavation. The crews used shovels, picks, wheelbarrows, steel bar stone-breakers, and ten-ton hydraulic jacks. These instruments were often used on an experimental basis conducted by Washington Roebling. The work progressed slowly at an rate of six inches per week. By the fall of 1870 the crews had achieved a stone and mud height of 500 feet for the first tower. This tower was completed after a year of work in March 1871.
Wires and CablesThe building of the Brooklyn Bridge was also extremely significant because many new materials and manufacturing techniques were invented for the project. John Augustus Roebling created the first wire rope manufacturing company in America in the 1840s. His knowledge and use of the wire ropes turned out to be extremely helpful as Roebling began to plan the Brooklyn Bridge construction. The wire rope allows the metal to maximize its strength by sharing a heavy load among the individual cast steel wires. Roebling created these steel cast wires specifically for the Brooklyn Bridge and spun them at the bridge site to ensure they were the correct length.These cables became the key structural component of the Brooklyn Bridge. Steel was still considered a “new” product and had not faced the test of time, and many thought iron was a wiser choice. Washington Roebling faced a scandal when a wire contractor substituted weaker and cheaper Bessemer steel for the cast steel. However, Roebling designed the wires to be six times stronger than necessary, so he expected the “faulty” wires were still five times stronger than needed. Roebling ultimately decided these wires did not need to be replaced. |








