At the tone, the time will be ...

... eight, forty-seven, and thirty seconds ...

BEEP

For anyone who doesn't know what I'm referring to, you used to be able to get the exact time of day by calling a telephone number. Why, you ask, would anyone want to do that? Because, once upon a time, there was no other way to get the exact time of day. There were no cell phones or computers. If you didn't wind your watch (battery and quartz watches weren't invented) or clock, they would stop. Electric clocks would stop during power outages. If you didn't know what time it was, how would you find out? 

The Cambridge Tribune, Volume XLI, Number 15, 8 June 1918, page 12

Until 1918, people would call the operator. An operator, dear children, was a human that answered the phone when you dialed 0 - just 0 - on a rotary phone. People called the operator for all sorts of reasons: to report a fire or look up someone's phone number; to get sports scores, news headlines, or the weather; or to get the time of day so you could set your watch. The operator was like a search engine in human form. Interesting factoid for those of us who remember the rotary phone: the 0 was placed at the end of the dial (after the 9, instead of before the 1) because it was thought to be easier to find in the dark or in an emergency. 

After 1918, when the service was no longer provided by phone operators, people could call their jeweler, utility company, or Western Union. However, by 1920 New York City established a dedicated phone line where operators did nothing but tell you the time of day. The time was told to you by another human being who did nothing but tell people what time it was.

It wasn't until 1933, that the process became automated. AT&T provided the service and callers would heard a recorded human voice. You can hear what it sounded like here: Telephone World.

And if you want to know the official time today, you can still call the U.S. Naval Observatory at 202-762-1401.

Or you can just look at your phone.