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According to my Watch

As I write this column, it is nine seconds past 10:30 a.m. and the temperature near my computer keyboard is a balmy 72 degrees Fahrenheit. Yep, I can tell that just from looking at the watch my wife bought me.

She obviously understands men. How else would she realize how important it is for me to know that, right at this moment, I am at 5,536 feet altitude, with a barometric pressure of 827 hPa? After extensive research (which consisted of looking up hPa on the Internet because reading the manual on my watch wouldn't have been a technological enough thing to do), I discovered that an hPa is a hectopascal, which is the same as a millibar, and there are 0.02953 of them in an inch of mercury.

Yep, I'm pretty sure that means there's some weather outside. In fact, I just may go out there and look at lunchtime. But that's beside the point.

We've come a long way since the first LCD watches were introduced. Remember those? They cost hundreds of dollars, and all they could do was tell the time. Nowadays, even the watches you get free with your Happy Meal have lap timers, stopwatches, calendars, and the ability to solve simple differential equations.

The most important advance in timekeeping technology is the ability to know exactly what time it is. I'm not talking about within a minute or two. I'm talking about precision here.

Let's take my house, for example. We have approximately 673 clocks in our house. There are clocks on the oven, the microwave, the stereo, the VCR, and the bread maker. We have a grandfather clock, four wall clocks, at least 300 alarm clocks, clocks in our computers, and clocks in our cars. And none of them agree on the time.

"You're fifteen minutes late," I tell my daughter, pointing at the grandfather clock. "No, I'm ten minutes early," she says, pointing at the microwave.

Well, modern technology has solved this problem.

Back in the dark ages of the mid 1990s, this great country depended upon a time standard called the NIST-7, an atomic clock at the National Institute of Standards and Technology. Problem was, this clock had some reliability trouble. You see, every million years or so, it could gain or lose almost a tenth of a second. Disturbed by this horrible inaccuracy, Steve Jefferts and Dawn Meekhof of NIST designed and built the Cesium Fountain Atomic Clock, which can run for 20,000,000 years without gaining or losing a second. Now we're talking.

Any good watch and clock store will be pleased to sell you a watch that sets itself using radio broadcasts from the NIST. No longer do you have to worry about being a tenth of a second late for an appointment. Your watch will be right.

Of course, that's not good enough for NIST. They're now working on an optical clock that uses "an energy transition in a single trapped mercury ion." They believe it will be 1,000 times more accurate than the clock Steve and Dawn slaved over for four years.

But think about this a moment. How will they know? Can't you just picture a group of guys standing around at the NIST in a billion years saying, "Hey-this atomic clock is a second slower than the other one. Which one is right?"

I may be a few seconds slow now and then, but I am content and secure in the knowledge that the barometric pressure has dropped by a full hectopascal while I was writing this, which probably means that a hurricane is coming. Maybe I'll go read the users manual for my watch after all!

Gary D. Robson is a writer and technology consultant, and he missed his last deadline by four seconds because he doesn't have an atomic clock of his own yet.