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An X-Ray View of a Busy Half-Mile Under the Ground on the Jersey Side of the Hudson River

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Cross-Section on Sixth Avenue at Thirty-third Street, New York

1.Foot Passage4.New Rapid Transit Subway
2.Manhattan Elevated Railroad5.Hudson and Manhattan Railroad Station
3.Street Surface and Metropolitan Street
Railway		6.Pennsylvania Railroad Tunnel

Finally the difficult situation was met by obtaining two large and heavy mainsails, which made a double canvas cover measuring about sixty by forty feet. This canvas cover was then spread on a flat barge, small sections of pig iron being attached around the edges of it. Ropes were carried to fixed points to hold it in exact position. The barge was then withdrawn, and the canvas cover dropped to the bed of the river, and, most fortunately, it settled over the point where the leak had occurred, and a large number of bags of dirt were then deposited on it. An opening was then made in the bulkhead of the tunnel below, and for eight days material, under hydrostatic pressure, forced its way into the tunnel, where it was loaded on cars, and finally the canvas was drawn into the hole, stopping it up. Additional material was then deposited into the river to fill the cavity, and finally the tunnel was recovered, pumped out and work resumed. This event is of somewhat historical interest, in that the two mainsails which were used were procured from the owner of the famous American cup defender, the well-remembered “Reliance.”

Probably the most unique and interesting pieces of construction are the three junctions on the Jersey side of the river, where the uptown tunnels from New York diverge, north to Hoboken and south to Jersey City and New York downtown. For safe and expeditious operation of trains, where the schedule is only one and one-half minutes, it was imperative that grade crossings should be avoided. By grade crossings is meant the tracks of one service crossing the tracks of another service at the same grade. At the point in question, this was a knotty problem to solve, owing to the unusual operating conditions which had to be met, there being six separate and distinct operating classes of trains to be handled around this triangle.