An escalator is an moving stairway that transports people from one floor to the other. Escalators are there at airport, stores and subway stations. The invention of the escalator was made by two American inventors named G. H. Wheeler and W. Reno in 1892.
The first contact lenses were invented by A.E Fick in 1887 but were not very successful. In about 1950, successful lenses were introduced which covered only the cornea and floated on a layer of tears. These lenses, only 7 to 10 millimeters in diameter of 0.1 to 1 mm thick can usually be worn all day without being removed .
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