Tomorrow will be the last day in the 213-year history of the New York Stock Exchange that the exchange will exist as a member-owned not for profit. With the scheduled closing of a merger between the NYSE and Archipelago Holdings Inc., the exchange will become a company traded on the NYSE whose shares can be bought by members of the public. It’s the latest chapter in a remarkable New York story that began when stockbrokers gathered on May 17, 1792, under the shade of a buttonwood tree on Wall Street.

In testimony before Congress in 1934, the man who was then president of the New York Stock Exchange, Richard Whitney, tried to warn off the would-be federal regulators. “You gentlemen are making a great mistake,” he said. “The Exchange is a perfect institution.” It was not then and will never be. But it has, through adaptation, confounded its critics from that day to this.

Lately, the advent of digital technology has threatened the so-called specialist system; could not these mere mortals charged with making markets in listed common stocks be replaced by a not very large computer server? Well, the Big Board has brought in the technology and, in effect, challenged the human beings to keep up with it. The planned acquisition of Archipelago Holdings and subsequent sale of stock to the public confounds the many who predicted that the big building at the corner of Broad and Wall was going to wind up a bowling alley.

In our lifetime, the exchange has undergone sweeping changes on matters as varied as commission rates (they have plummeted) to the kind of firm permitted to deal in listed stocks. Some have worried that the movement of stock trading to the Internet would make the physical location of Wall Street irrelevant. But somehow the seat-holders of the exchange have adapted in a way that, as of the scheduled closure of the deal tomorrow, will make them richer than ever.

No doubt some small amount of the change of the exchange is attributable to pressure from New York’s attorney general, Eliot Spitzer, though he will still have to prove in court his judgment that the compensation of the NYSE chief executive, Richard Grasso, was unreasonable. But stock exchanges are merging and moving to electronic trading and going public and making money all over the world, even without Mr. Spitzer’s prodding. Feature the examples of Euronext or the Nasdaq-Instinet merger. What this merger and public offering is about mainly is not government intervention but capitalist creativity and competitive pressure.

Two decades ago a publicly-traded, computer-trading oriented, for-profit New York Stock Exchange might have been as unimaginable as, say, the idea that JP Morgan, Chase, Chemical, and Manufacturers Hanover banks might all end up merged together. Right now, it seems unlikely to many that the city’s tradition-bound hospital or primary and secondary education sectors will follow the stock exchange down the path toward a free-market, for-profit structure. But the pressures toward rationalization, adaptation, and survival in New York extend beyond Wall Street. So the prospect that new setup at the stock exchange will inspire change in other far-flung quarters of the city’s economy is not something that we would – not to put too fine a point on it – sell short.