culties while coincidentally before
entering a rock reef which presented another serious difficulty in
construction. The experience then in the construction of this tunnel led
capitalists and engineers to believe that, owing to the very soft nature
of the ground, a tunnel could not be built that would be sufficiently
stable to withstand the vibration due to heavy traffic, and for this
reason tunnels under the North River were not looked upon as
practicable. The writer devised a scheme to carry within the tunnel the
rolling loads on bridging supported on piers or piles extending from
the tunnel invert down to hard material. These would be attached to the
tunnel itself or would pass into it independently through sliding joints
in the tunnel shell. This scheme gained the confidence of the
management, as it was believed that, by adopting such a plan, tunnels
could be built in the soft material underlying the Hudson River and
remain stable under all conditions of traffic. After thus feeling
assured that by this method the tunnels could be made safe beyond
question, orders were given to proceed with the great work of the
extension into New York of the Pennsylvania and Long Island Railroad
systems.

[Illustration: FIG. 1.--(Full page image)

ENGINEERING STAFF ORGANIZATION

CHIEF ENGINEER
|
CHIEF ASSISTANT
ENGINEER
|
|
+--(CHIEF OFFICE)
| |
| +--OFFICE ENGINEER
| | |
| | +--Chief Draftsman.
| | Draftsmen.
| | Messenger.
| |
| +--MECHANICAL ENGINEER
| | |
| | +--Mechanical Draftsmen.
| |
| +--ASSISTANT ENGINEER
| |
| +--Accountant.
| Clerks.
| Telephone Operators.
| Messenger.
|
|
+--(TERMINAL STATION WEST)
| |
| RESIDENT ENGINEER
| |
| +--Assistant Engineer.
| | Chief of Party.
| | Instrumentmen.
| | Rodmen.
| | Chainmen.
| |
| +--Inspectors.
| |
| +--Clerk.
| Janitors.
|
|
+--(SUBAQUEOUS, 32ND STREET AND WEEHAWKEN TUNNELS)