Who first demonstrated his safety mechanism for elevator operation at the 1853 New York World's Fair?
Elevator to take effect if the cords broke. It consisted of a beam pushed outwards by a steel spring. In 1852, Elisha Otis introduced the safety elevator, which prevented the fall of the cab if the cable broke. He demonstrated it at the New York exposition in the Crystal Palace in a dramatic, death-defying presentation in 1854, and the first such passenger elevator was installed at 488 Broadway in New York City on 23 March 1857. The first elevator shaft preceded the first elevator by four years. Construction for Peter Cooper's Cooper Union Foundation building in New York began in 1853.
Space elevator safety Space elevator safety There are risks associated with never-done-before technologies like the construction and operation of a space elevator. A space elevator would present a navigational hazard, both to aircraft and spacecraft. Aircraft could be dealt with by means of simple air-traffic control restrictions. Impacts by space objects such as meteoroids and micrometeorites pose a more difficult problem for construction and operation of a space elevator. If nothing were done, essentially all satellites with perigees below the top of the elevator would eventually collide with the elevator cable. Twice per day, each orbital plane intersects the elevator, as the rotation