economy is on a firmer footing. And since that horrendous crash, much has been done to forestall a repeat debacle. For example, brokerage firms and mutual-fund companies have invested billions of dollars in technology so that they can answer all the calls and execute all the trades on the busiest days. The New York Stock Exchange, which has never traded even 1 billion shares in a day, currently has the capacity to trade 3 billion shares. On the computerized Nasdaq stock market, capacity was a mere 250 million shares a day in 1987 and is now 1 billion shares, headed for 1.5 billion shares by the end of the year. The N.Y.S.E. has adopted trading rules that prevent certain computerized stock trading when the Dow is up or down 50 points in a day; the "sidecar" rule gives small orders priority when the market is moving briskly; and "circuit breakers" halt trading for 30 minutes when the Dow is down 350 points and for one hour when it is down 550 points. The rules ensure that investors have time to think.So are we safe from another Black Tuesday? We can never be sure when the next fall will occur, we can be sure however that it will happen, thus our concern should be to minimize the damage caused by the market fluctuations. There is a feeling among investors that the wisdom learned from past market troubles is protecting us now, weather in the form of changes to the Federal Monetary policy or the installation of circuit breakers. This all leads to the optimism of the boom we have experienced since the mid 90's, the booming stock market is a natural result of profound economic changes both here and abroad. For starters, the end of the cold war not only has allowed governments to stop spending capital on the arms race and freed up money for more productive uses but it has opened up huge new markets like Russia and Eastern Europe. Companies are focusing on making money by producing goods more efficiently rather than by raising prices, thus infla...