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Everyday things, one question at a time

Why bread rises, how a clock keeps time, who decided a week has seven days. Each entry takes one question about something ordinary and answers it properly, with the history and the mechanism a reader can actually explain to someone else.

Food and drink · tools and machines · customs and calendars · the ordinary things with a long story

How did time zones get invented?

Time zones were invented in stages between 1870 and 1884: American schoolteacher Charles F. Dowd proposed hourly zones for U.S. railroads in 1870, Canadian railway engineer Sandford Fleming proposed a worldwide 24-zone…

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