Mobile Post Office Society Information

rpo marking special delivery stamp


Mobile? Post Office?

A moving Post Office? What is that? You may have thought of post offices as big buildings full of busy clerks and (sometimes) long lines.

Since the advent of the railroad in the early 1800's the history of the post has been characterized by an emphasis on greater and greater speed of delivery. Someone very smart had the great idea of not only using the railroads to quickly move messages from sender to recipient, but also as an actual mail handling facility: a moving post office.

The United States Post Office operated a remarkable system where special postal clerks rode in their own (secure) car, sorting mail as the trains flew between the major (and some not-so-major) cities. In addition to sorting the mail for the destination cities on the route, the mail clerks caught outgoing mail from small towns, sorted it on the fly, and could drop bags of sorted mail from the train at the next small town, all in a few quick minutes. [Note that the RPO clerks had to know the scheme for an entire destination city, while the city clerks often only had to know a particular neighborhood.] To handle the mail from small towns where the express train did not stop, the outgoing mail bag was hoisted onto a special crane, and the RPO car had a special device to "snag" the mail bag as the train sped past. Delivered mail bags were just tossed off the moving train.

Such mobile post office facilities were also used in many non-U.S. countries.

Trolley Car Mail

Around 1900, trolley cars were a very popular means of mass transit in U.S. cities. Some enterprising local postmasters figured out that they could put clerks on such special trolley cars, and have them perform the same type of sorting and distributing taking place on the big trains. These systems grew for a while, but were mostly gone by 1920. Mail was handled on electric trolleys, cable cars, and even special horse-drawn cars.

How to Collect this Mail

RPO mail can be found from early in the 19th Century mail system, up into the 1960's in the United States. Some RPO systems still operate in Europe, and possibly other countries. Collectors usually look for the cancellations indicating a particular route, particular railroad line, or perhaps all RPO routes from a particular state. If you visit some railroad museums, you can see actual RPO cars, some with mockup configurations as they would have run. A few museums have actual retired postal clerks who show people "how it was done". Sadly, the clerks from the heyday of the RPO system are passing from the scene. Some of these clerks helped to found the Mobile Post Office Society.

About the Society

The Mobile Post Office Society was founded in 1950 as HPO Notes. Its goal is to study the transportation of the mails by all types of conveyance. The Society has published monographs on subjects ranging from U. S. waterways postmarks, to trolley car Railway Post Office (RPO) histories and markings. The Society has branched out, and now includes Rural Free Delivery (RFD) under its umbrella.

The Society is currently developing a newly updated listing of all US RPO markings (originally written by the late Charlie Towle). To say the least, this organization is very aggressive about publishing, and all collectors with any interests in this area should investigate the large selection of monographs available from the Society.

The Transit Postmark Collector is published bimonthly as the official journal of the Society. The editor is:

Douglas N. Clark
PO Box 427
Marstons Mills MA 02648
e-mail: dncjkj7969y868@math.dsh3h4h5r988ugaekj98ru23ueu6.edup89ru4u34e5ri

Membership information is available from Mr. Clark, who is also Secretary of the Society.

There is a webpage for the Mobile Post Office Society.

Latest Transit Postmark Collector

Even though the information in the following announcement is a bit out of date, it still gives you a good idea of the very interesting content in the Transit Postmark Collector .

Transit Postmark Collector is published bimonthly as the official journal of the Mobile Post Office Society.

Transit Postmark Collector
Vol. 66, No. 1 (November-December 2014)



... is in the mail!

Will Keller's HPO column is a return to the Rock Island & Effingham HPO. The reorganizations of 1963 are described, with schedule plates, a map and markigs reproduced. Will also reviews an article on HPO #1 the Washington DC & Harrisonburg, VA HPO, apearing in Bus Industry Magazine.

In News from the Cities, David Gentry illustrates street car covers with dates which turned out to be important for (nonphilatelic) reasons.

New railroad postmarks are illustrated, submitted by various collectors.

Society business includes minutes of the Board meeting in Milwaukee.

There is a mail bid sale and much more ...


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