[Tunnel construction.]

[North tunnel shield.]

[Constructing the McAdoo Tunnel.]

[Holland Tunnel.]

Original Exhibits of Rapid Transit Subway Construction Company, Plaintiff [Excavating a tunnel; subway construction.]

Midtown Tunnel under Hudson River, April 24, 1935

[Construction of the Pennsylvania Railroad tunnels under the Hudson.]

Queensboro Tunnel.

Queensboro Tunnel.

Queensboro Tunnel.

[McAdoo Tunnel.]

[Central Park.]

[Tentatively, east 50th Street, view of construction site.]

[Unloading ring from truck.]

Building the McAdoo Tunnel, Under the Hudson River, New York.

[Construction in Central Park.]

[Holland Tunnel.]

[McAdoo Tunnel.]

[Holland Tunnel.]

Southbound express tunnel.