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Nikola Tesla’s earthquake machine

He takes credit for over 300 inventions, but there are few of them which were never built. His imagination takes them to the very top.
Tesla patented a steam-powered mechanical oscillator that would vibrate up and down at high speeds to generate electricity in 1893. Thanks to its magnificent power during the test, walls started to crack, people taught that an earthquake stroke and the machine was never completed giving it the name earthquake machine. Tesla said he had to break the machine with a hammer when he realized that the building might collapse.
Police and ambulances arrived on the scene, but Tesla told his assistants to remain quiet and tell the police that it must have been an earthquake.