Door Knocker

Until 1916, Americans were not required to have household letter boxes. Letter carriers handed over the mail personally, ringing the bell twice to signal that the mail was there, or knocking. Door knockers like this one saved wear and tear on the knuckles.

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Narrator: The postman always rings twice.

Have you ever wondered where that phrase came from?

For decades after home mail delivery began, this was true because letter carriers handed mail over in person.

The typical doorbell signal was two rings.

Of course some homes didn't have doorbells.

Carriers got tired of knocking so they carried wooden knockers like this one.

But efficiency experts determined that two hours were being lost each day while postman waited for patrons.

So in 1916, the post office mandated mailboxes or mail slots for all homes.