June 12 is the birthdate of John A. Roebling (1806), a civil engineer noted for his wire rope suspension bridge designs, particularly the Brooklyn Bridge. Born in Mühlhausen in Prussia, he began producing wire rope at Saxonburg, Pennsylvania, in 1841. In 1844 he won a bid to replace a canal aqueduct across the Allegheny River with the Allegheny Aqueduct, followed in 1851 by a railroad bridge over the Niagara River. In 1867 he started design work on what is now called the Brooklyn Bridge, spanning the East River in New York. With a main span of 1,595.5 feet, it was the world’s longest suspension bridge from its opening in 1883 until 1903, and the first steel-wire suspension bridge. Roebling devised "an equilibrium strength approach, in which equilibrium is always satisfied but compatibility of deformations is not enforced." In 1869, however, Roebling’s foot was crushed by a ferry while he stood at a dock’s edge to fix the location where the bridge would be built. His injured toes were amputated, he refused further medical treatment, and he died of tetanus 24 days after the accident.