The escalator is a continuous moving staircase that carries people from one level or floor to another. A series of steps are pulled by chains along two sets of tracks, powered by an electric motor.

The first United States patent for an escalator was issued in 1859, but the invention wasn't used. The practical escalator was the result of independent inventions in the early 1890s by two Americans, Jesse Reno and Charles Seeberger. Reno invented an inclined belt with a grooved tread for steady footing. Seeberger produced a flat-step design with side entrance. A problem with both designs, however, was the stationary handrail.

During the 189Os, the Otis Elevator Company acquired rights to these two designs. Otis put several escalators into operation at its factory in Yonkers, New York, in 1899. The first public installations of an escalator were at the 1900 Paris Exposition and in the New York City elevated...