According to http://world.nycsubway.org/us/path/hmhistory.html
"The Downtown Tunnels The downtown river tunnels, on the other hand, came no closer than 90 feet and at the state line are 240 feet apart. They were built through mud and rock at a depth of 60 to 90 feet below mean low water level, and were 15 feet, 3 inches in diameter, lying 15 to 40 feet below the bottom of the river. Part way under the river sections of tube were placed under the westbound tunnel to permit the proposed third and fourth "Erie" tracks to diverge from the route to Exchange Place; the headings for these additional tunnels may still be seen between the existing tunnels just outside Hudson Terminal." "Two additional tubes were started at Hudson Terminal to provide express service direct to the Erie Station. However, because of a lack of funds they were never completed. In another proposal, the Erie Railroad wanted a spur built from the existing tunnel near the H&M Station under Pavonia Avenue to a new station directly under the Erie Terminal.
http://inlinethumb42.webshots.com/17897 ... 600Q85.jpg
"The Downtown Tunnels The downtown river tunnels, on the other hand, came no closer than 90 feet and at the state line are 240 feet apart. They were built through mud and rock at a depth of 60 to 90 feet below mean low water level, and were 15 feet, 3 inches in diameter, lying 15 to 40 feet below the bottom of the river. Part way under the river sections of tube were placed under the westbound tunnel to permit the proposed third and fourth "Erie" tracks to diverge from the route to Exchange Place; the headings for these additional tunnels may still be seen between the existing tunnels just outside Hudson Terminal." "Two additional tubes were started at Hudson Terminal to provide express service direct to the Erie Station. However, because of a lack of funds they were never completed. In another proposal, the Erie Railroad wanted a spur built from the existing tunnel near the H&M Station under Pavonia Avenue to a new station directly under the Erie Terminal.
http://inlinethumb42.webshots.com/17897 ... 600Q85.jpg
Bring back the Slumbercoaches!!