
The SciencesMarch 1, 1939
Boring through a Rainstorm
San Jacinto Tunnel, Part of Colorado River Aqueduct System, Presented Engineering Difficulties, Rock and Water, Pioneer Tunnels Driven Ahead

Boring through a Rainstorm
San Jacinto Tunnel, Part of Colorado River Aqueduct System, Presented Engineering Difficulties, Rock and Water, Pioneer Tunnels Driven Ahead