French, Archie W., photographer. still image Lantern slides 1900-1920. gmgpc [between 1903 and 1914] eng Bird's-eye view of construction of canal lock. No. 7. Locks (Hydraulic engineering)--Panama--Canal Zone--1900-1920. Canal construction--Panama--Canal Zone--1900-1920. Panama Canal (Panama)--1900-1920. http://hdl.loc.gov/loc.pnp/cph.3b42900