In 1888 Theophilus Van Kannel Invented the Revolving Door

Theophilus Van Kannel invented the revolving door in 1988. It became the entrance for the modern skyscraper. The revolving door served as an airlock, preventing the rapid influx of cold air into warm buildings on chilly, windy days. The revolving door was also useful in keeping out street noises, fumes and other outdoor elements.