1. Photocopy from George S. Morison's The Sioux City Bridge, 1890. Photographer unknown, circa 1889. SOUTH WEB AND WEST PORTAL OF BRIDGE
HAER SD,64-SIOCI,1-1AISSON PIER IV, 60 FEET BELOW WATER LINE, 25 POUNDS AIR PRESSURE
HAER SD,64-SIOCI,1-4sd/sd0000/sd0018/photos152545pt.gifw1152545pr.jpg|152545pv.jpg|152545pu.tif ʐ2. Photocopy of photograph, original in the possession of John R. Morison, Peterborough, New Hampshire. Photographer unknown, circa 1889. EAST PORTAL OF BRIDGE
HAER SD,64-SIOCI,1-2 BELOW WATER LINE, 25 POUNDS AIR PRESSURE
HAER SD,64-SIOCI,1-4sd/sd0000/sd0018/photos152546pt.gifx2152546pr.jpg|152546pv.jpg|152546pu.tif ʐ3. Photocopy from George S. Morison's The Sioux City Bridge, 1890. SITE PLAN OF BRIDGE
HAER SD,64-SIOCI,1-3pher unknown, circa 1889. EAST PORTAL OF BRIDGE
HAER SD,64-SIOCI,1-2 BELOW WATER LINE, 25 POUNDS AIR PRESSURE
HAER SD,64-SIOCI,1-4sd/sd0000/sd0018/photos152547pt.gifw3152547pr.jpg|152547pv.jpg|152547pu.tif ʐ4. Photocopy of photograph, original negative in the possession of John R. Morison, Peterborough, New Hampshire. Photographer unknown, 14 September 1888. INSIDE CAISSON PIER IV, 60 FEET BELOW WATER LINE, 25 POUNDS AIR PRESSURE
HAER SD,64-SIOCI,1-4sd/sd0000/sd0018/photos152548pt.gifw4152548pr.jpg|152548pv.jpg|152548pu.tif ʐ