Movable form for concrete pour for lock

Photograph showing a close-up view of one of the giant movable forms used to pour the concrete walls of the lock chamber. The rear of crane appears on the right.
Abstract/Description: Photograph showing a close-up view of one of the giant movable forms used to pour the concrete walls of the lock chamber. The rear of crane appears on the right.
Subject(s): Boats and boating
Soo Locks (Mich.)
Date Created: 1912 (approximate)