German inventor Ferdinand von Zeppelin granted a patent for the navigable balloon.
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Solymon Merrick patented the wrench tool.
A patent was awarded to Willis Carrier, which gave us the world’s first Air Conditioner.
Robert Goddard was granted a patent for the rocket-powered aircraft.
A polygraph test was conducted by its inventor, Leonarde Keeler, for the first time.
American inventor Eli Whitney was granted a patent for a ground-breaking new type of cotton gin.
