 The pneumatic subway line that Ray finds when they lower him below  the street actually exists under part of Manhattan. The line was  built prior to any other subways in the area and was actually built  without any City approval. It operated using compressed air and  pushed Victorian New Yorkers a number of blocks in "elegant  comfort". When the City of New York found out about the subway line,  they shut it down and the line was buried, including two beautifully  appointed stations with extensive tile work and even full