Site Map


National Postal Museum

Smithsonian National Postal Museum

skip navigation

About the Museum
The Collection
For Educators
Stamp Collecting
Getting Involved
Activity Zone
Museum Library


Customers and Communities : Serving the Cities : Carriers & Mail Delivery : Pneumatic Tube Mail

Pneumatic Tube Mail

Pneumatic tube canister
Pneumatic tube canister

Networks of pneumatic tubes speeded mail along under city streets beginning in the 1890s. Mail was enclosed in pneumatic tube canisters that could hold up to 600 letters. The canisters traveled at an average of 35 miles per hour.

The first pneumatic tubes were introduced in 1893 in Philadelphia. Boston, Brooklyn, New York, Chicago and St. Louis also used the system. By 1915, these six cities had more than 56 miles of pneumatic tubes pulsing under the streets.

During World War I, the Post Office Department suspended the service to conserve funding for the war effort. After the war service was restored in New York and Boston. By the 1950s, it became clear that the end of pneumatic tubes was in sight as increasing mail volumes and changing urban landscapes made it impractical. While post offices and businesses moved with relative ease, the underground pneumatic system did not.

Map of the New York City pneumatic tube lines
Map of New York City pneumatic tube lines

Pneumatic tube service

Image (at left):
Clerks working with the pneumatic tube system in a New York City post office building.

Photograph of pneumatic tubes and machinery in post office basement

Image (at left):
Pneumatic tubes were placed in the basement facilities of post offices.

Back to Top