Commander Emerson Jones working with aerial photographs.

Leveling across Isthmus of Panama.

Level crew. Burger, Boone, Libby, Babcock, Peterson. Level crew of W. H. Burger

Level crew with velocipede. Holtzmann on car. Level party of B. E. Tilton

Taking a backsight. Level party of W. H. Burger

Rodman holding rod vertical during observations.

Rear rodman passing front rodman, recorder pulling. Passing the mallet so rear rodman can drive spike to steady rod. Level crew of W. H. Burger

Observer riding ahead. Level crew of W. H. Burger

W. H. Burger observing. Note standing straight up to observe - minimizing fatigue. Level crew of W. H. Burger

First order leveling. Mechanized leveling with velocipede. Party of M. E. Lutz

First order leveling. Mechanized leveling with velocipede. Party of M. E. Lutz

First order leveling. Mechanized leveling with velocipede. Party of M. E. Lutz

Showing how line of sight clears recorder with inclined tripod. Mechanized leveling with velocipede. Party of J. D. Crichton

Level setup on motor velocipede. Level center-mounted on velocipede

Level setup with inclined tripod on motor velocipede. J. D. Crichton observing. Party of J. D. Crichton

Crew with motor velocipedes and inclined level. Party of J. D. Crichton

Recording instrument mounted on left side of velocipede. Party of J. D. Crichton

Working along the Southern Pacific Railroad. Rodman at benchmark. Observing crew even with engine on right. Velocipede removed from tracks. Level party of C. A. Egner

Observing from level mounted on velocipede. Level center-mounted on velocipede. Crossing trestle on Southern Pacific Railroad. Level party of C. A. Egner

Level crew with the tools of the trade. Level party of Caspar Durgin

Level crew with the tools of the trade. Sub-party of H. W. Hough. Level party of H. W. Hough

Level crew in the Arizona desert. Level party of Fred E. Joeckel

Leveling down the trail into Glen Canyon. Level party of Fred E. Joeckel

Leveling down the trail into Glen Canyon. Level party of Fred E. Joeckel

Connecting the line - two level crews meet in Glen Canyon, Colorado River. Level parties of Fred E. Joeckel and Floyd W. Hough

The boat - means of transportation in Glen Canyon, Colorado River. Level party of Fred E. Joeckel

Level crew in boat in Glen Canyon, Colorado River. Level party of Fred E. Joeckel

Connecting the line - party chiefs shaking hands. Fred E. Joekel on left - Floyd W. Hough on right

Leveling observations between Valdez and Fairbanks. Level party of Herman Odessey

Entering a tunnel on motor velocipede. Sure hope nobody's coming the other way. Level party of Herman Odessey

Setting the velocipede back on the tracks after train passes. Level party of Herman Odessey

Mosquito protection in Colorado. Level party of Glendon Boothe

Rodman Fisk holding the level rod steady. Level party of Glendon Boothe

First order leveling in Atlanta. Level party of E. O. Heaton

Leveling on Alameda Boulevard in Los Angeles. Level party of Glendon Boothe

Beginning a spur line into Mokuaweoweo Crater. Leveling in support of gravity operations on Mauna Loa. Party of Lansing Simmons

The last setup on the summit of Mauna Loa. Party of Lansing Simmons

Leveling up Mount Whitney. Level party of John Brittain

Leveling up Mount Whitney. Level party of John Brittain

Level party at the top of Mount Whitney. Level party of John Brittain

Level party trying to stay warm in Washington. Level party of Charles Pierce

Using dynamite to excavate a bench mark hole. Note dirt flying out of hole. Level party of H. J. Oliver

First C&GS logo T-shirt. Level party of H. J. Oliver

Driving pin for steady rod support. Level party of Al Thorson

Checking the computations at the end of the day.

Speeder and trailer. Motor velocipede leveling. Level party of Ernst Stohsner

Levels lunch. Trying to stay warm on a cold day. Level party of Charles Pierce

Setting bench marks in Utah. Level party of H. J. Oliver

Bench mark truck showing mounting of water barrel. Setting bench marks in Utah. Level party of H. J. Oliver

Observing party truck showing mounting of rod box. Level party of H. J. Oliver