July 28, 1868 – U.S. Secretary of State William H. Seward announces the ratification of the 14th amendment by the states, granting citizenship to ex-slaves.
July 30, 1975 – Former Teamsters Union leader James “Jimmy” Hoffa is last seen outside a restaurant in Detroit, Michigan. He is declared officially dead in 1982.
July 31, 1790 – The U. S. Patent Office opens and issues the first patent to Samuel Hopkins for a new method of making potash (fertilizer). The patent is signed by George Washington and Thomas Jefferson.
August 2, 1923 – President Warren G. Harding dies suddenly in San Francisco while on a Western speaking tour. The following day Calvin Coolidge is sworn into office. Harding’s legacy is tainted by the Teapot Dome oil lease scandal that comes to light following his death.