Why Was the American Depression of 1929 so Sudden and so Severe?

In what regards the depression, the main reason was 'The Wall Street Crash'. In the 1920s the stock market shares went skyrocketing at an incredible and alarming rate therefore people could speculate their rise and make fortunes out of this. Ironically it was speculation itself what brought 'The Wall Street Crash' upon the American people. In Thursday, October 24, also known as 'Black Thursday' 12,894,650 shares changed hands, many of them at such low prices that destroyed any dream or future that the people who had owned them had optimistically thought of. By 11:30 AM the market had turned into a wild rush to sell, people were running around in panic trying to recuperate at least some of their money, the Police had to keep their eyes wide open in case any tragedy would happen. Eleven well-known speculators had already killed themselves. …