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An American, Charles D. Seeberger, invented moving stairs to transport people (0).....C... the 1890s. He (11) .......... this invention an 'escalator', (12) .......... the name from the Latin word 'scala', (13) .......... means 'ladder'. Escalators move people up and down short (14) .......... Lifts do the same, but only move (15) .......... small number of people. If an escalator breaks down, it can still be (16) .......... as ordinary stairs. An escalator can move (17) .......... 8,000 and 9,600 people an hour, and it (18) .......... not need a person to operate it.

Towards the end of the nineteenth century, cities were (19) .......... more crowded and the first escalators were built at railway stations and in big department (20) .......... so that people could move about more quickly. Today we see escalators everywhere.