An earthquake on Dec. 16, 1811 caused parts of the Mississippi River to flow backwards.
During the 1811/1812 New Madrid (Missouri) earthquakes, church bells were heard as far as Boston and Toronto, and sidewalks cracked in Washington DC.
'... (2am), we were visited by a violent shock of an earthquake, accompanied by a very awful noise resembling loud but distant thunder, but more hoarse and vibrating, which was followed in a few minutes by the complete saturation of the atmosphere, with sulphurious vapor, causing total darkness. The screams of the affrighted inhabitants running to and fro, not knowing where to go, or what to do - the cries of the fowls and beasts of every species - the cracking of trees falling, and the roaring of the Mississippi - the current of which was retrogade for a few minutes, ... formed a scene truly horrible.' (Full report.)