from cryptogon/wikipedia: The Wall Street Crash of 1929... was the most devastating stock market crash in the history of the United States, taking into consideration the full extent and longevity of its fallout. Three phrases - Black Thursday, Black Monday, and Black Tuesday - are used to describe this collapse of stock values. All three are appropriate, for the crash was not a one-day affair. The initial crash occurred on Black Thursday (October 24, 1929), but it was the catastrophic downturn of Black Monday and Tuesday that precipitated widespread panic and the onset of unprecedented and long-lasting consequences for the United States. The collapse continued for a month.