Machine cancel

Machine cancellation was the solution to ever-increasing amounts of mail that needed processing. Beginning about 1875, various companies were building and selling machines for cancelling mail.

The style of cancellation often follows hand cancellation styles with a postmark with the town and date and time frame, called a dial, placed to be struck away from stamps. There is a killer/obliterator portion consisting of bars or lines, sometimes including a number or letter code for identifying a particular machine. Some versions use a continous cancellation that runs across the entire envelope for maximum coverage. Sometimes, the killer portion can be replaced by an image and/or message. These are called slogan cancels.

The machines can be used for applying other postal markings like receiving cancels.

There are sufficient identifying characteristics and styles to identify manufacturers.

Where older machines essentially print cancels, the United States has gone to spray-on cancels that appear in the style of old dot-matrix printers.  File:Cortland NY machine.jpg|1907 US Cortland, NY cancel (Doremus type). File:Canada Toronto flag.jpg|1898 Canada Toronto flag cancel. File:US Albuquerue.jpg|1924 Albuquerque, New Mexico cancel. Note how this card slipped in the machine, requiring a postal clerk to manually cancel the stamp. File:Argentina slogan.jpg|1944 Argentina slogan cancel "Help victims of the San Juan (earthquake)". Note continuous impression. File:Germany Leipzig Herbst messe.jpg|1938 Herbst Messe ("Autumn Fair") slogan cancel. File:US Bishop flag.jpg|1925 US Bishop, California flag cancel. 