CBS News Correspondent Lee Cowan reports on time and its watchers.
Perhaps it's no coincidence that the thousands who cram into New York's Times Square every December eventually look up -- lifting their bloodshot eyes to the night sky to ring in the New Year.
Long before that sparkling ball dropped through the darkness, looking up into the heavens was our best way of telling time.
"If you think back to times when people weren't distracted by neon lights, television, street lights, the sky was the greatest show on earth," says science writer Dava Sobel, whose books include "The Planets," "Galileo's Daughter," and "Longitude."
Measuring the dance of light across the heavens, she says, was a daily challenge both magical and necessary.
"When the world was lit only by the sun, the moon, the planets and fire," says Sobel, "there was no better way to reckon time."
We could easily experience the solar day, measured from one sunrise to the next.
Then there was the lunar month: the length of time it took the moon to become full again.
And when the seasons came full circle again, we witnessed the passing of a solar year.
"The natural time divisions don't naturally mesh neatly with each other," says Sobel. "In trying to combine them, we wind up with things like 'Thirty days hath September, April, June and November.' "
And that's where we were for thousands of years. We had no concept of minutes or hours - let alone seconds.
For more on that, we turned to William J. H. Andrewes, an expert in the history of scientific instruments and time measurement who collaborated with Sobel on "The Illustrated Longitude," which includes the history of the chronometer, a clock that keeps precise time at sea.
Almost as long as he can remember, Andrewes has been studying time and every conceivable way of measuring it.
"I became interested in clocks when I was about 16 years old," says Andrewes, admiring the craftsmanship on a nearby timepiece.
Officially he's a horologist - the traditional name for a clockmaker.
He's also a scholar who has taught at Harvard University.
Man's pursuit of time, in Andrewes' view, is the pursuit of heavenly perfection.
"If you graduate from college and get a 99 percent, you get the highest honors. If you're a clockmaker and your clock is 99 percent accurate, you've failed," he observes.