Spruce Creek tunnel.

Columbia Tunnel.

Railroad tunnel and tracks through mountain.

Tunnel.

Traverse Road East, Central Park.

The entrance of the Shawangunk Tunnel, on the east side.

The entrance of the Shawangunk Tunnel, on the west side.

The Breckneck Tunnel.

The Tunnel in the Jackson Iron Mine.

Hoosac Tunnel, east portal and mountain.

Hoosac Tunnel, east portal and mountain.

Hoosac Tunnel, east portal and mountain.

Interior view of Hoosac tunnel.

Hoosac Tunnel.

The new air compressors which furnish power to drive the drills, about 500 feet below the surface of the earth.

The new air compressors which furnish power to drive the drills, about 500 feet below the surface of the earth.

Miners descending the west shaft with the Burleigh Drill.

Dam on the Deerfield.

East end of tunnel, showing bed of road.

East end of tunnel, showing bed of road.

West end from the original surface standpoint, looking north-east.

West end, showing the brick arch.

West end, showing the brick arch.

Miners descending the west shaft.

View of the central shaft after a naptha explosion (1867) where thirteen were killed, showing people at the top of the shaft awaiting the recovery of bodies.

Lover's retreat near nat. bridge.

Natural bridge, looking down stream.

Natural bridge, looking up stream.

Stone dam at glan mill.

Hoosac house and mountain.