The 19th century, in fact, was very advanced in the transmission of correspondence. ... Pneumatic tubes carried messages (pneus) around major cities in Europe and even North and South America. "...The system was large enough to carry small parcels,... and on one occasion a cat was even sent from one post office to another along the tubes" (Standage: 97).
Susan S. Lukesh, E-Mail and Potential Loss to Future Archives and Scholarship or The Dog that Didn't Bark in First Monday Vol. 4 No. 9 - September 6th. 1999