Wiktionary
pneumatique
n. (context historical English) The pneumatic postal system in Paris (abolished 1984), or a letter sent by this system.
Usage examples of "pneumatique".
If you will simply send a pneumatique giving me your address, I will be able to explain everything.
In the Rue de Rennes he found a post office where he bought a pneumatique letter-card, wrote in it his name and that of his hotel, addressed it to Mr.
If they did not come, they would send him a pneumatique telling him where to meet them.
Sometimes they would send a pneumatique telling him to meet them at the Dome or the Rotonde.
Stopping to buy a new commutation ticket at the Pneumatique, he passed the time with an Esper 3, on duty at the Information Desk, who passed Fred the word about Barbara D'Courtney.