ATLANTA — This weekend we spring forward and lose an hour of sleep, meaning many people across metro Atlanta will hit the snooze.

For most of us, the snooze will bring an extra nine minutes of slumber.

Why nine minutes? It seems kind of random.

History holds the answer.

The snooze feature was added to alarm clocks back in the 1950s. Early clock makers wanted the snooze time to last ten minutes, but those early mechanical clocks involved a lot of moving gears. It was impossible for clock makers to get the gears of the hour and minute hand to mesh perfectly with the snooze feature.

“Mechanically, you could not adjust it to where it would do it exactly at ten minutes,” says Jeff Champion of Champ’s Clock Shop in Douglasville. “That was the mechanical limits of a mechanical clock.”

Clockmakers had to decide if the snooze would be a little longer than ten minutes or a little less. Fearing more than ten minutes would allow the clock owner to slip back into a deep sleep (and risk being late), they picked nine minutes.

Of course, clocks are more sophisticated now. Manufacturers could set the snooze to any time they want. But often they default to nine minutes out of a sense of nostalgia. Even iPhones have set the snooze to nine minutes.

“That’s paying tribute to the original snooze alarm clock,” says Champion.

So get your extra nine minutes of rest and enjoy being a part of alarm clock history.

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