What are some of the causes for the 1929 US stock market crash?

The 1920’s were a booming time for Americans as the stock market was surging due to speculative investing.  Stock prices rose to records heights which drove the public to invest their liquid assets into securities.  Billions of dollars were drawn from banks for broker’s loans to carry margin accounts.  People were mortgaging their homes to pour money into stocks.  In late 1929, the market eventually overheated and prices began to fall despite efforts by the banks to buy up large blocks of stock to stem the losses.  Eventually, the panic was too much and the market crashed on Black Monday, October 24th when the market closed down 12.8 percent.  The sharp decline in the 1929 stock market eventually led to the Great Depression of the 1930’s.