Borings (2 of 7)

Concrete boring 22-G16A, 41.2 Ft to 57.8 Ft  and 22-16A 57.8 Ft to 80.8 Ft, Electronic reproduction of photograph.  The Mackinac Bridge 1954 - 1958. Mackinac Bridge Authority
Abstract/Description: Concrete boring 22-G16A, 41.2 Ft to 57.8 Ft and 22-16A 57.8 Ft to 80.8 Ft
Subject(s): Bridges--Design and construction
St. Ignace (Mich.)
Mackinaw City (Mich.)
Mackinac Bridge (Mich.)
Date Created: 1955 (approximate)