15

In a flash!

A comparatively simple network of underground tubes was used to send postal items through Berlin. The sender delivered it to one of the connected post ofices and the letter wasplaced into a special cartridge. A machine generated underpressure that drew the cartridge into the tube. Alternating between pressurised air and suction air the letter shoot war transported through the system with a speed of ten to fifteen meters per second. In the early days they were directed manually at intermediate stations, later electromagnetic gates automatically send the cartridge to the post office closest to the recipient’s address, where a cycle messenger already waited to deliver the letter.
In 1865 this pneumatic delivery system, the most advanced of its time, started operations between the main post office in Oranienberger Strasse and the stock exchange (at the site of todays S-Bahn Station Hackescher Markt).