Elevators began as simple rope or chain hoists. In the past elevator drive mechanisms were powered by steam and water hydraulic pistons. In 1823, an "ascending room" made its debut in London. In 1853, Elisha Otis introduced the safety elevator, which prevented the fall of the cab if the cable broke.On March 23, 1857 the first Otis elevator was installed at 488 Broadway in New York City. The first elevator shaft preceded the first elevator by four years. Construction for Peter Cooper's Cooper Union building in New York began in 1853. An elevator shaft was included in the design for Cooper Union, because Cooper was utterly confident a safe passenger elevator would soon be invented. The first electric elevator was built by Werner von Siemens in 1880. The safety and speed of electric elevators were significantly enhanced by Frank Sprague.