1902, Americus F Callahan, Granted the Patent for Window Envelope On this day on June 10, 1902, Americus F. Callahan of Chicago, Illinois, in the United States, granted the first patent for Window Envelope. The United States patent number for Callahan’s design is
1869, Thomas Edison Granted His First Patent On this day June 01, 1869, American inventor and businessman Thomas Alva Edison granted his first patent for the Electric Vote Recorder (U.S. Patent 90,646). Electric vote recorder for use by legislative bodies such as Congress.
1906, US Patent for the World’s First Air Conditioner On this day during on January 2, 1906, Willis Carrier received the world’s first air conditioner US patent. He was an American engineer who first developed modern air conditioning systems that helped