Underground secrets of New York City

From Curious Expeditions, a fascinating article on the pneumatic tubes once used to send mail underground across New York City. Here's a bit:

Put into operation in New York in 1897 by the American Pneumatic Service Company the 27 mile system connected 22 post offices in Manhattan, and the the General Post office in Brooklyn. The pipes were between 4 to 12 feet underground, and in some places the tubes ran along the subway tunnels of the 4, 5 and 6 lines. At the height of its operation it carried some 95,000 letters a day, or 1/3 of all the mail being routed through out New York city.

Quoted in “Underground Mail Road” Nathan Halpern, a veteran postal worker, said in an internal newsletter. “I still remember those canisters popping out of the tube,”They were spaced one every minute or so, and when they came out, they were a little warm with a slight slick of oil.”

James A. Farley Pneumatic StationThere is something deeply romantic about the notion of handwritten sentiments, tear stained even, flying at 35 mph underneath the feet of an unsuspecting New York. Receiving a love letter through the veins of the city only minutes after it was written, ink still damp and the smell of your beau’s perfume still lingering on the paper. Somewhere in the depths of the massive James A. Farley Post Office was the major control room of the Pneumatic system. As seen in the picture postal worker loaded cartridge after cartridge of notes, family correspondence, love letters, and shot them through the dark vast network. Small torpedoes of love, finance and ideas.

The system was discontinued in the 1950s although some of the tubes do still remain. The authors reference Kate Ascher's book The Works: Anatomy of a City for more information on the system and also photographs.