Standard Time

Daylight Saving Time ends tonight. We’ll set our clocks back an hour as we revert to Standard Time.
Standard Time wasn’t always standard, though. In fact, the time zones we use today weren’t formalized until 100 years ago.
For the first century of American history, timekeeping wasn’t much of an issue. People didn’t travel much, and they certainly didn’t travel very far. So it was most convenient for cities and towns to keep their own time. It was noon when the Sun reached its highest point in the sky. In some cities, the time was kept by observatories, which had telescopes for measuring the Sun’s position.
But as railroads expanded in the 19th century, standard time zones became important. Trains ran through thousands of cities and towns, with the clocks set a little differently in each one. That made scheduling tough and confusing.
Scientists were concerned about timekeeping, too. An astronomer, for example, had set up the country’s first network of weather observers. But coordinating