I’m not sure if William Clayton simply was tired of being asked, "Are we there yet?" or if he was just an observant fellow, but in any case he and his fellow wagon train buddies gave birth to the modern odometer, where a separate gear controls each digit, all the way back in 1847.
Mr. Clayton noticed that 360 revolutions of a wagon wheel equaled approximately a mile, so he attached a red flag and counted its revolutions. Anyone who has been stuck in a "time out" and forced to count to some insanely high number (my son would argue that 10 would qualify) can tell you that such a task gets old very quickly. Mr. Clayton discussed things with a few of his wagon train buddies and the roadometer was born!
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