Jetable mail

You're referring to "jetable mail"!

Jetable mail, also known as "jetable" or "jetable post", is a type of postal service that was popular in the 19th and early 20th centuries. The term "jetable" comes from the French word "jeter", which means "to throw" or "to cast".

In the context of postal services, jetable mail referred to a system where letters or packages were thrown or tossed from a moving train or other vehicle to a recipient at a designated stop or station. This method of delivery was often used in rural areas where traditional postal routes were not feasible or where the terrain was difficult to navigate.

The process of jetable mail typically involved a postal worker or a designated person on the train or vehicle tossing the mail bag or package to the recipient, who would then catch it or retrieve it from the ground. This method was often used for mail that was not time-sensitive, as the delivery time was not guaranteed.

Jetable mail was used in various countries, including the United States, Canada, and Europe. However, with the advent of modern transportation and postal services, jetable mail has largely been replaced by more efficient and reliable methods of mail delivery.