Beach Pneumatic Transit (NYC) - portal of the Broadway tunnel

The 1870 Beach Pneumatic System -- the NYC underground rapid transit system that could have been. Alfred Ely Beach, inventor and co-publisher of Scientific American, had a vision: an elaborate underground system run by massive fans that pushed and pulled cars through a tight tube. He even managed to build a prototype, which he put on display at the 1867 American Institute Fair. The fair-goers' enthusiastic reception to Beach's prototype encouraged him to take the next step and implement his idea underground. But Beach had one big obstacle: Boss Tweed. Tweed, a notoriously corrupt New York politician, had his own ideas about New York City transportation, and granting Beach permission to build something that might detract from Tweed's profits was simply not going to happen.  Knowing that a direct approach would be futile, Beach hatched a plan to secretly build what he wanted to build, right under Tweed's nose. Beach proposed an underground pneumatic mail distribution system, the likes of