Ernest Hallen, 1911, July, 58-I.- U.S. Marines on bridge built by them over Camacho Diversion at Bas Obispo - July 1911, Gelatin silver print, George A. Smathers Libraries, University of Florida, LL/58008

Ernest Hallen, n.d., 99-A Surveyers out in the Jungle. Locating Party, Gelatin silver print, George A. Smathers Libraries, University of Florida, LL/58005

Unidentified photographer, n.d., Boarding house proprietress and children, Photograph, George A. Smathers Libraries, University of Florida, LL/58006

I.L. Maduro Jr., n.d., Steam shovel at Pedro Miguel, Photograph, George A. Smathers Libraries, University of Florida, LL/58010

1915 (ca), Ledger book used as an album for photographs and postcards of Panama and the Panama canal zone, Accounting ledger book, with postcards, George A. Smathers Libraries, University of Florida, LL/58014

Ernest Hallen, n.d., 1 - Trackshifting Machine, Gelatin silver print, George A. Smathers Libraries, University of Florida, LL/58007

Ernest Hallen, 1907, 19 September, 19-C Immediately After Explosion - Bas Obispo Cut - September 19th, 1907., Gelatin silver print, George A. Smathers Libraries, University of Florida, LL/58000

Ernest Hallen, 1910, 1 April, 517 1/2 - K. Upper Locks, Gatun, Showing 208 1/2 ft. of East Side Wall Completed. April 1, 1910., Gelatin silver print, George A. Smathers Libraries, University of Florida, LL/58003

Unidentified photographer, 1911, 28 July, 518-Y6 - Gatun Upper Locks. View looking North, showing Progress of Construction on Upper Guard Gates, East Chamber, with Emergency Dam Sill in the foreground. July 28,1911, Gelatin silver print, George A. Smathers Libraries, University of Florida, LL/58004

Unidentified photographer, 1915, 10 April, 511-K50 - Floating Crane "Hercules" transferring equipment across Gatun Locks from east side. Looking south. April 10, 1915., Photograph, George A. Smathers Libraries, University of Florida, LL/58011

Unidentified photographer, n.d., Dirigible (blimp) flying above Sosa Hill, Balboa, Gelatin silver print, George A. Smathers Libraries, University of Florida, LL/58009

1915 (ca), Ledger book used as an album for photographs and postcards of Panama and the Panama canal zone, Accounting ledger book, with postcards, George A. Smathers Libraries, University of Florida, LL/58013

Fishbaugh (Empire, C.Z.), n.d., A Narrow street in Panama, Gelatin silver print, George A. Smathers Libraries, University of Florida, LL/58001

Ernest Hallen, 1907, 19 September, 19-B Explosion in Progress - Bas Obispo Cut - September 19th, 1907. 4 Holes - 78 ft. Deep - 9600 lbs. Black Powder - 29,640 cu. yds. Displaced., Gelatin silver print, George A. Smathers Libraries, University of Florida, LL/57999

Ernest Hallen, 1912, June, Panama Canal: Lock gates under construction, Gelatin silver print, George A. Smathers Libraries, University of Florida, LL/57998

1915 (ca.), Book cover for Ralph Emmett Avery & William C. Haskins, ca. 1915, Greatest Engineering Feat in the World at Panama, (New York: Leslie-Judge Co.), Book cover, George A. Smathers Libraries, University of Florida, LL/58012