INTERESTING FACTS CONCERNING HUDSON RIVER TUNNELS
 

Ballast......................Crushed Stone and Concrete

Ties................................White Oak

Steel Rail......................85 lbs. to Yard, A. S. C. E.

Inside Diameter of Iron Tunnel Rings..............15 Feet 3 Inches

Total Weight of Iron Rings.....................111,000 Tons

Total Amount of Cement Used for Concrete Construction......925,000 Barrels

Deepest Point in Tunnel Below Surface of River.............101 Feet

Average Thickness of Cover Between Top of Tunnel and Bed of River ....   25 Feet