The Clermont steamboat by Robert Fulton made its maiden trip up the Hudson River.
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Solymon Merrick patented the wrench tool.
The Bank of Italy opened in San Francisco, California, and would later become Bank of America.
Asaph Hall discovered Mars' second moon, called Phobos.
Younes Abouyaaqoub drove a van into pedestrians on La Rambla in Barcelona, Spain, killing 14 people and injuring at least 130 others.
American swimmer Michael Phelps became the first person to win eight gold medals at one Olympic Games.
