Good day and welcome to the second edition of Stamp Nook. Today we will be looking at pneumatic postal systems.
While a number of countries had pneumatic message delivery systems of some sort -- most notably the French Carte Pneumatique (or "pneu"), which was popular for sending love letters -- Italy is the only one to have issued stamps specifically for their pneumatic post. (Other countries instead used normal postal stamps or special stationary. Pity.) Italy started issuing pneumatic post stamps in 1913 for their five-city system and continued issuing until 1966, for a total of twenty-three stamps, including minor variations.
The stamp shown here is a 1945 Italian posta pneumatica issue (Scott D18) with a suspicious looking portrait of Galileo Galilei, based on Justus Sustermans' 1636 painting of Galileo at age 72. Galileo presumably was featured on a pneumatic post stamp for his work determining the vertical limit on suction pumps, which he set at 18 braccia. A similar design was previously used on an issue from 1933 (D16), and both were accompanied by issues of lesser face value that featured Dante Alighieri (D15 & D17), no doubt in honour of his literary contributions on the subject of subterranean travel.
Although Italy stopped issuing new pneumatic stamp designs in 1966, their system was apparently still in operation in 1974, but I am unable to find any more information on it.
Not including the heavily modernized system operated by the Republic of Cascadia Postal Authority (which hasn't issued any pneumatic stamps yet, but there's always hoping...), the only remaining pneumatic post system from the Golden Age of Pneumatic Tubes is in Prague. The Prague Pneumatic Mail System entered operation in 1899 for use in sending telegrams and was still in operation until the floods of 2002 (it is undergoing repairs). In it's later years the system has been used primarily by banks for sending original documents and by Czech Telecom to detect leaks in the adjacent gas lines. Quite a sad state of affairs. For more details, see: "I got root on the Prague Pneumatic Post".