Will a stock market crash, should it happen, be followed by another "Great Depression"? It depends which kind of crash. The short term puncturing of a temporary bubble - e.g., in 1962 and 1987 - is usually divorced from other economic fundamentals. But a major correction to a lasting bull market invariably leads to recession or worse. As the economist Hernan Cortes Douglas reminds us in "The Collapse of Wall Street and the Lessons of History" published by the Friedberg Mercantile Group, this was the sequence in London in 1720 (the infamous "South Sea Bubble"), and in the USA in 1835-40 and 1929-32. IV. Britain's Real Estate The five ghastly "Jack the Ripper" murders took place in an area less than a quarter square mile in size. Houses in this haunting and decrepit no man's land straddling the City and metropolitan London could be had for 25-50,000 British pounds as late as a decade ago. How things change! The general buoyancy in real estate prices in the capital coupled with the adjacent Spitalfields urban renewal project have lifted prices. A house not 50 yards from the scene of the Ripper's last - and most ghoulish - slaying now sells for over 1 million pounds. In central London, one bedroom apartments retail for an outlandish half a million. According to research published in September 2002 by Halifax, the UK's largest mortgage lender, the number of 1 million pound homes sold has doubled in 1999-2002 to 2600. By 2002, it has increased elevenfold since 1995. According to The Economist's house price index, prices rose by a further 15.6% in 2003, 10.2% in 2004 and a whopping 147% in total since 1997. In Greater London, one in every 90 homes fetches even a higher price. The average UK house now costs 100,000 pounds. In the USA, the ratios of house prices to rents and to median income are at historic highs. One is reminded of the Japanese boast, at the height of their realty bubble, that the grounds of the royal palace in Tokyo are worth more than the entire real estate of Manhattan. Is Britain headed the same way? A house - much like a Big Mac - is a basket of raw materials, goods, and services. But, unlike the Big Mac - and the purchasing power index it spawned - houses are also investment vehicles and stores of value. They yield often tax exempt capital gains, rental income, or benefits from occupying them (rent payments saved). Real estate is used to hedge against inflation, save for old age, and speculate. Prices of residential and commercial property reflect scarcity, investment fads, and changing moods. Homeowners in both the UK and the USA - spurred on by aggressive marketing and the lowest interest rates in 30 years - have been refinancing old, more expensive, mortgages and heavily borrowing against their "equity" - i.e., against the meteoric rise in the market prices of their abodes. According to the Milken Institute in Los Angeles, asset bubbles tend to both enhance and cannibalize each other.