I watched Bahubali yesterday and my hypothesis has achieved 100% significance. I think the inventor of the Revolving Door is Kattappa, just like many other inventions from Ancient India. Though H. Bockhacker of Berlin was granted German patent DE18349 on December 22, 1881 for “Tür ohne Luftzug” or “Door without draft of air”, which used a rotating cylinder with a door which after entering, the … Continue reading The inventor of the revolving door is Kattappa