Smart Machines

Some of the modern pioneers of the Internet are well known: Gordon Moore, Vint Cerf, Bob Metcalfe, Tim Berners-Lee, Marc Andreesen. (And then there's, uh, Al Gore.) In truth, hundreds, if not thousands, of people have been responsible for the creation, funding, development, and expansion of the Internet. The handful of people who are now famous for its invention have become household names because their roles have been extraordinarily influential and highly visible. However, with the passage of time the credit will likely settle on a single person. Curiously, today it is almost impossible to predict who that person will be; we are still too close to the Web's early development.

As an example of the mystery surrounding a similar technological advancement, we can look at the invention that sparked the industrial revolution a little more than 200 years ago: the steam engine.

Who invented the steam engine? Most schoolchildren think they know the answer: James Watt. However, Watt didn't invent the steam engine itself; he invented ways to boost the engine's efficiency. At the time of Watt's improvements, steam engines had been used for a long time to pump water out of mines. Those engines were designed and built by Thomas Newcomen (1663-1729).

But Newcomen was just fine-tuning another man's invention. In the first century A.D., Heron of Alexandria published a remarkable book titled Pneumatica. This work contains descriptions of several steam-driven devices, including a turbine steam engine called an "aeolipile." According to the descriptions, Heron's devices were used mostly to amuse or to impress -- for example, to open heavy temple doors seemingly automatically. Heron probably would have been quite startled to witness the changes that a systematic use of steam engines set in motion many centuries later.

So clearly, James Watt was one of many who helped to bring about the industrial revolution. Why, then, are all those other inventors forgotten and only Watt's name is remembered? Some have suggested that this may have happened because of a single visible and highly imaginative contribution of Watt's: the steam governor. The steam governor (now often called Watt's governor) consisted of two heavy metal balls suspended from two movable arms, spinning on a vertical axis. The axis was driven by the running steam engine. As the engine's speed increased, the metal balls slowly separated, propelled by centrifugal force. As they moved, they pulled a lever, which in turn moderated the speed of the engine.

As the engine's speed changed under varying loads, the steam governor could immediately compensate for the changes and force the machine to maintain a constant speed -- a remarkable insight of automation based on the feedback-control principle. That principle of operation could be compared to the automatic cruise-control system of a car. When your car goes uphill and the engine consequently slows down, the cruise-control system detects and compensates for that effect by increasing the supply of fuel by just the right amount to maintain speed.

The operation of Watt's governor was simple, but unlike other equally important improvements that Watt and those before and after him had made, it was easy to observe and understand. The genius of the steam governor's function could be appreciated by anyone who watched the engine in operation. It had "PR value."

So who invented the Internet? We can only guess which of several names will wind up in the history books. But one thing's for sure: we know who won't be there. Sorry, Al.

Gerard J. Holzmann is a researcher at Bell Laboratories in Murray Hill, N.J.

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