The history of civilization is the history of the struggle for human rights. Basic in this struggle is free communication on equal conditions. Progress in the facilities for such communication has made the United States postal service a democratic institution.
—Daniel C. Roper, First Assistant Postmaster General, 1917

Machines Move the Mail

Six clerks sorting mail in a city post office.
Visitors to large city post offices from the 1870s to the 1970s would have seen postal clerks tossing mail into mail sacks. Clerks had dozens of pieces of mail to sort in a minute.

In some big cities, city post offices were designed as factories behind an elegant façade. Inside, buckets and conveyor belts moved the mail through the system. Canceling machines marked the postage stamps.

Automobiles joined ships, trains, streetcars, and pneumatic tubes as machines that moved the mail. As the machinery of the postal system changed, it still connected families and businesses around the world.

Throwing Mail Into Bags
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Postal workers sorted some mail by tossing it into bags. This short, 57-second, silent video was produced by the "American Mutoscope & Biograph Company" in 1903. Notice the stage backdrop painted to resemble the interior of a post office.

[silent video]

Over There
From the battlefield in France to Linwood, Maryland

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Postcard from soldier

An American soldier writes a postcard home, reassuring his family that he’s surviving in France, and takes it to the American Expeditionary Force post office.

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US Mail trucks in France

A U.S. Post Office worker drives the military mail to the port in France before being placed on board a ship bound for New York City where it arrives a week later. At the New York City post office, the postcard is dropped into a pouch for Maryland.

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Mail being transferred from train to trucks in France.

A wagon carries the pouch to Pennsylvania Station and it’s placed on the Railway Post Office car in the southbound New York and Washington train. The postcard is sorted en route into a pouch for the Baltimore and Cumberland RPO car, and transferred in Baltimore.

Railway Post Office car
Mail is sorted aboard Railway Post Office car

In the Baltimore and Cumberland RPO, the postcard is sorted again into a pouch for Linwood. As the train passes Linwood, the pouch is thrown from the car, and a mail messenger picks it up and carries it to the Linwood post office.

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Clerks sorting mail in a post office.

Sorted by hand in the post office, the soldier’s postcard is taken on a Rural Free Delivery route and dropped in an RFD box where his family picks it up.

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Rural Free Delivery wagon
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American Postal Machines Company stamp canceling machine
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Pitney Bowes Model A M meter machine

Systems at Work