Thanks to all,
Jesper, thanks for the reminder about AskPhil. I have no excuse about not going there; I simply forget about that site all the time
Nick, I have neither of the references that you cite. I need to get Wood's book sometime. Probably need to get both - some day.
I take it that this is an intra-city system for transporting among neighborhood post offices. It couldn't possibly be for sending mail between cities
Even so, I can't envision an air-propelled system (even with vacuum assistance) working for more than a few hundred feet.
That must have been not only an extremely air-tight tube, but also a virtually frictionless system.
Can you imagine this kind of technology in the 1860s (France and Germany)?
Now I have several more questions (as is typical) which I shall research.
1. Since the first Italian pneumatic stamps were issued in 1913, I guess at least one of the systems was partially in operation by then. Wonder which one(s)?
2. It appears that the pneumatic post rates were higher than the regular post rates. I wonder if the pneumatic system was pitched to the populace as an expedited delvery system commanding a premium? Or if the premium was added just to pay for the construction?
I may have to send Gini Horn at the APS library an email. [Now I wonder what their schedule is for moving the library into its new home.]
In any event, it must have been an exciting time to work for the Italian post system, what with the pneumatic system being built, the experimentation with delivering mail by airplane, etc. Then again, being in the middle of WWI adn having Benito Mussolini's rise to power in the 1920s being on the horizon - perhaps it was not all that exciting.