On January 17, 1899, U.S. Patent No. 617,778. issued to Charles D. Seeberger on an  escalator.

Seeberger did not actually invent “the” escalator, as there were several earlier patents, including to Souder U.S. Patent No. 406,314 in 1889 (which was never built), to Reno U.S. Patent No. 470918 in 1892, and Wheeler U.S. Patent No. 479864 in 1892 (which was never built).  Seeberger bought Wheeler’s patent, teamed with Otis, and in 1899 produced the first commercial escalator, which won the first prize at the Paris 1900 Exposition Universelle in France.