The Rise of Vending Machines
In the early 1900s, automated stamp vending and affixing machines were becoming highly popular for businesses and the general public. These machines required stamps to be arranged in long, continuous rolls (coils) rather than traditional, bulky sheets.
The Government Experiment
To meet this demand, the Bureau of Engraving and Printing (BEP) produced an experimental batch of coils. Because they did not have specialized rotary presses yet, they used regular flat-plate sheets of 400 stamps. These sheets were perforated in only one direction, cut into vertical strips of 20, and then pasted end-to-end to form large rolls.
Ignored and Overlooked
Because this was an off-the-cuff, temporary experiment, collectors and post offices were largely unaware the stamps existed. The rolls were sent to only a few select cities (Washington D.C., Indianapolis, and Baltimore) for testing in vending machines. The public and postal workers actually complained about these early issues, as the perforations were too close together and the stamps easily fell apart.