The Brooklyn BridgeThe Brooklyn Bridge’s construction is one of the great achievements in United States history and helped pave the way for New York City’s rapid expansion in the 19th and 20th centuries. It was an undertaking that required extraordinary effort, sacrifice, and ingenuity by its designers as well as its builders to complete. Its completion was a feat of engineering that was unmatched in its time: it was the longest suspension bridge—the first to use steel-wire—and dominated the New York City skyline as the tallest structure in the western hemisphere (Hiden 476).The idea of a bridge linking Manhattan to Brooklyn was first formalized in a petition to the state legislature in 1802 (Feuerstein 24). From the time Dutch settlers arrived in Brooklyn in 1636, there had been a need to travel between Manhattan and Brooklyn (Feuerstein 98). There were many factors that made constructing a bridge there difficult, though. The East River was a wide and busy waterway with large ships and was surrounded by a low-lying area. This required that the bridge have a high clearance to enable ships to enter, be longer than any bridge built before it and have a significant curve. For these reasons, the idea for the bridge was continuously put off in favor of ferry services. Brooklyn’s population continued to swell though, and between 1860 and 1870, it experienced a colossal increase from 266,000 to 396,000 (Feuerstein 19). The City of New York at the time consisted only of Manhattan, which had about double the population of Brooklyn. A bridge was seen as a way to relieve overcrowding in Manhattan, while at the same time aid in the expansion of Brooklyn. A man named John Roebling came up with the idea for the bridge in 1855 when he became frustrated while waiting for a ferry in 1855 (Logson 341). Roebling was born in 1806 in Germany where he trained to be an engineer. He immigrated to the United States in 1831 and after a failed attempt at making a living as a farmer in Pennsylvania, he found work as a civil engineer (Logson 342). He originally worked on canals and in the process of designing them, he found that he needed better rope. He came up with a new design and method of creating flexible wire ropes and received a patent for this in 1842 (Logson 342). He quickly found additional uses for the invention, one of which was bridges. He completed his first major bridge in 1855, which was the Niagara River Gorge Bridge (Logson 344). After several more successful projects, Roebling began to lobby influential people in New York for a bridge he had designed to cross the East River. In 1867, an act was passed to raise funding for the bridge and two years later, the design for the Brooklyn Bridge was approved. The same month the plans were approved, Roebling’s foot was crushed by a ferry and he soon after died of tetanus (Logson 345). His son, Washington, took over and ground was broken on the bridge on January 3, 1870 (Logson 346). The main design feature of the bridge were four fifteen-inch diameter steel cables that would support the enormous expanse of the bridge, which was to be over 6000 feet (Switch 22). In order to support those cables, the towers had to be enormous and they had to be sunk to the bedrock below the East River. The method for digging the river bottom was to sink a wooden box using pressurized air and create an elevator so that workers could be lowered to the box which was called a caisson. In order to pressurize the air, other gases had to be used which were potentially toxic. At least two dozen people died during the construction, most of which occurred from this phenomena. Workers were raised to the surface too quickly and experienced what were referred to as the bends. Roebling’s son, Washington, was himself paralyzed due to this, after which point his wife took charge of the project (Switch 23). Granite finally reached 78 feet down on one side and 44 feet on the other and the towers were eventually finished in 1877. The construction of the roadway began in 1878 and finally finished in 1882. By 1883, the longest suspension bridge in the world was finished after thirteen years of development and construction. The opening ceremony was attended by U.S. President Chester A. Arthur and was hailed as the 8th wonder of the world. Not long after Brooklyn became part of New York, the three other boroughs followed shortly thereafter. It far surpassed what was thought of as possible for bridges at the time and laid the foundation for the rapid expansion of bridge building throughout the country. It also allowed New York to expand rapidly by allowing the easy flow of traffic to and from Brooklyn and defined what we today think of as New York City.Topic Outline:Ⅰ.The Introduction of The Brooklyn BridgeⅡ.The idea of a bridge linking Manhattan to Brooklyn in a petition to the state legislature in 1802Ⅲ.A man named John Roebling with the idea for the bridge in 1855Ⅳ.The main design feature of the bridgeⅤ.（）The above outline is not complete, but which of the following could fit the missing part?（）
A.The construction and completion of the roadway B.The opening ceremony C.8th wonder of the world D.The rapid expansion of bridge正确答案A
