Photograph of hydraulic monitoring on American Hill. Visible in the photo are monitors, pipe, and tailing piles.
Inscription recto: Hydraulic Method of Washing Gravel On American Hill Photo by J. Doody Dawson
Photograph of hydraulic monitoring on American Hill. Visible in the photo are monitors, pipe, and tailing piles.
Inscription recto: Hydraulic Method of Washing Gravel On American Hill Photo by J. Doody Dawson