At ten o’clock on the morning of 29 October 1929 the gong sounded in the New York Stock Exchange on Wall Street for the start of business. What followed was an unseemly, desperate scramble to sell stocks and shares at any price. One thing was clear above the din of shouting traders: the American boom of the 1920s had crashed in flames. At the end of the day 16 million shares had changed hands at knock-down prices. When the Dow-Jones Index stopped its downward fall in July 1933, $74 billion had been wiped off share values, and shares stood at only 15 per cent of the level on that day in 1929 when the crisis began.