I think this was first started in the Scottish isles and , if I remember correctly , did work and was the part of some amateur research in rockets.
Amateur research in rockets between the wars all over Europe eventually led to Werner von Braun . There is a great book called The Rocket Men about this development.
Now I read the details, the Scottish Rocket Mail was a disaster on the launch pad, and the German responsible went back to be arrested for collaborating with the British. The book was The Rocket Team, and although interesting, is remarkably brutal.
( could have changed the course of history though if the rocket mail had worked)
Last edited by Sunfish; 09-06-2019 at 12:59 PM.
Reason: Added brackets.