It was a quiet day on the Delaware River in 1817 -- until the tsunami
Tuesday, September 10, 2013 - 17:30
in Earth & Climate
A "tidal wave" violently tossed ships docked along the Delaware River south of Philadelphia at about 11 a.m. ET on Jan. 8, 1817, according to newspapers of the time. Turns out, that tidal wave was actually a tsunami, launched by a powerful magnitude-7.4 earthquake that struck at about 4:30 a.m.