ROEBLINGS AND BRIDGE BUILDING: A FAMILY STOREY Family John Augustus Roebling (born Johann August Röbling, June 12, 1806 in Mühlhausen - July 22, 1869) was a German-born civil engineer famous for his wire rope suspension bridge designs, in particular, the design of the Brooklyn Bridge. The eldest son of John Roebling, Washington Augustus Roebling, was born in Saxonburg, Pennsylvania, a town co-founded by his father and his uncle, Karl Roebling. His early schooling consisted of tutoring by Riedel and under Henne in Pittsburgh. He eventually attended the Trenton Academy and acquired further education at the Rensselaer Polytechnic Institute in Troy, New York, from 1854-57. Following his graduation as civil engineer (C.E.), he joined his father to work as a bridge builder. From 1858 to 1860, he assisted his father on the Allegheny Bridge project, living in a boarding house on Penn Street. Following the completion of the bridge, he returned to Trenton to work in his father's wire mill. After the completion of the Brooklyn project, Roebling and his wife Emily Roebling, lived in Troy, New York, from 1884-88, as their only child, John A. Roebling, II, also attended the Rensselaer Polytechnic Institute (RPI). When their son graduated, the Roeblings returned to Trenton, moving to 191 West State Street in 1892. From 1902-1903 Roebling served as President of the Alumni Association at Rensselaer. His wife Emily died in 1903 from stomach cancer. Roebling remarried in 1908 to Cornelia Witsell Farrow of Charleston, South Carolina. His namesake, Washington Augustus Roebling II, only son of his brother Charles G. Roebling, went down with the RMS Titanic in 1912. Following the sudden death of his nephew, Karl Gustavus Roebling, in 1921, Roebling again became president of John A. Roebling's Sons Company at age 84. He died in 1926, after being bedridden for two months, at age 89. Roebling's most passionate hobby was collecting rocks and minerals. His collection of over 16,000 specimens was donated by his son, John A. Roebling, II, to the Smithsonian Institution and became an important part of its mineral and gem collection. A plethora of his manuscripts, photographs, and publications, can be found in the Roebling collections at Rutgers University in New Brunswick, New Jersey, and at Rensselaer Polytechnic Institute in Troy, New York. Roebling's 3rd son Charles Roebling designed and invented the 80 ton wire rope machine and founded the town of Roebling, New Jersey where the John A. Roebling and Sons company steel mill was built. His grandson, Washington A. Roebling, II, died on the RMS Titanic. His great-grandson, Donald Roebling was a noted philanthropist and inventor who devised the amphtrack. Legacy: The Brooklyn Bridge, New York, USA In 1867 Roebling started design work on what is now called the Brooklyn Bridge, spanning the East River in New York. Roebling proposed a bridge of 465m, with two masonry towers in the Esat River serving as main piers. The bridge actually built is longer-486m, the longest suspension bridge up to that time. It was the first bridge to make use of galvanized steel wire; earlier suspension bridges used either wrought iron cables or suspension chains. The cables were spun on site from a previously built footbridge. Massive anchorages for the cables had to be built, as there were no natural formations to support them. The bridge carried two elevated railroad tracks, two trolley car tracks, single lane roadways flanking the trolley tracks, and a central walkway. Stiffening trusses were added to insure against sway- a characteristic of suspension structures. Disaster struck early in the history of the bridge. One day in 1869, even before construction commenced, Roebling was standing on the edge of a Brooklyn wharf to carry out survey for the main piers, when a ferry collided with the bulkhead of the wharf. His foot was crushed and his injured toes were amputated. He refused further medical treatment and wanted to cure his foot by "water therapy" (continuous pouring of water over the wound). While in the hospital, Roebling demanded constant updates on the progress of his greatest work and continued to help solve onsite problems. But his condition deteriorated until it was clear he had tetanus, and 24 days after the accident he was dead. Roebling's son Washington Roebling and his daughter-in-law Emily Warren Roebling continued his work on the Brooklyn Bridge for the following 14 years. Washington Roebling’s health was also doomed to suffer from the bridge. After working for long hours at high atmospheric pressure, he collapsed with decompression sickness in May 1872. He was partly paralyzed and was able to supervise construction only through binoculars from his balcony. But his wife, Emily, threw herself into the study of engineering, and was soon able to inspect the site each day. Emily was to relay information from Washington to his assistants and report the progress of work on the bridge to her husband. She developed an extensive knowledge of strength of materials, stress analysis, cable construction, and calculating catenary curves through Washington’s teachings. For the next fourteen years, Emily’s dedication in aiding her husband in the completion of the Brooklyn Bridge was unyielding. She dealt with politicians, competing engineers, and all those associated with the work on the bridge to the point where people believed she was behind the bridge’s design. It was suspected at the time that she was even more involved with the project, inputting her own ideas and making crucial alterations to the designs. People were worried that the bridge was partly the work of a woman, and this was thought to be highly dangerous! In 1882 the Mayor of Brooklyn resolved to replace Washington Roebling on the ground of physical incapacity. Emily Roebling requested permission to address the American Society of Civil Engineers, the first time that a woman had done so- and as a result Washington Roebling remained the Chief Engineer of this project. After the opening ceremony in 1883, many citizens and officials marched to his home to honor Washington Roebling. Emily herself took the first ride across with the President of the United States. The opening ceremony was attended by several thousand people and many ships were present in the East Bay for the occasion. President Chester Arthur and New York Mayor Franklin Edson crossed the bridge to celebratory cannon fire and were greeted by Brooklyn Mayor Seth Low when they reached the Brooklyn-side tower. Arthur shook hands with Washington Roebling at Roebling's home, after the ceremony. Washington Roebling was unable to attend the ceremony but held a celebratory banquet at his house on the day of the bridge opening. Further festivity included the performance of a band, gunfire from ships, and a fireworks display. On that first day, a total of 1,800 vehicles and 150,300 people crossed what was then the only land passage between Manhattan and Long Island. The bridge's main span over the East River is 1,595 feet 6 inches (486.3 m). The bridge cost $15.5 million to build and approximately 27 people died during its construction In recognition of her work, the Emily Roebling Scholarship is given to deserving female Engineering students at Rensselar Polytechnic University, New York. One week after the opening, on May 30, 1883, a rumor that the Bridge was going to collapse caused a stampede, which crushed and killed at least twelve people. On May 17, 1884, P. T. Barnum helped to squelch doubts about the bridge's stability—while publicizing his famous circus—when one of his most famous attractions, Jumbo, led a parade of 21 elephants over the Brooklyn Bridge. At the time it opened, it was the longest suspension bridge in the world — 50% longer than any previously built — and it has become a treasured landmark. For several years the towers were the tallest structures in the Western Hemisphere. Since the 1980s, it has been floodlit at night to highlight its architectural features. The towers are built of limestone, granite, and Rosendale cement. Their architectural style is neo-Gothic, with characteristic pointed arches above the passageways through the stone towers. Brooklyn Bridge was the first long-span suspension bridge to carry motor traffic, and it quickly became the model for the great suspension bridges of the following century and also an icon of New York City. Today the Brooklyn Bridge holds a plaque dedicating the memory of Emily, her husband, and her father-in-law. It was designated a National Historic Landmark in 1964. At the time the bridge was built, the aerodynamics of bridge building had not been worked out. Bridges were not tested in wind tunnels until the 1950s — well after the collapse of the original Tacoma Narrows Bridge (Galloping Gertie) in 1940. It is therefore fortunate that the open truss structure supporting the deck is by its nature less subject to aerodynamic problems. Roebling designed a bridge and truss system that was six times as strong as he thought it needed to be. Because of this, the Brooklyn Bridge is still standing when many of the bridges built around the same time have vanished into history and been replaced. This is also in spite of the substitution of inferior quality wire in the cabling supplied by the contractor J. Lloyd Haigh — by the time it was discovered, it was too late to replace the cabling that had already been constructed. Roebling determined that the poorer wire would leave the bridge four rather than six times as strong as necessary, so it was eventually allowed to stand, with the addition of 250 cables.
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