Leveling through the snow. Level party of Ira Rubottom

First order level observations in Brazil. Special training mission of Joseph Lushene

Zeiss level instrument at the Instituto Geographico Militar. Special training mission of Joseph Lushene

Leveling upper mark with accuracy only to cms. Special training mission of Joseph Lushene

Level party crossing bayous near Dugdemona River. Level party of R. C. Darling

Not the best bridge, but it will work. Level party crossing bayous near Dugdemona River. Level party of R. C. Darling

C. F. Ellingwood recording during leveling of White House. Level party of Howard Rappleye

E. J. Parkin observing levels at White House, South Portico. Level party of Howard Rappleye

Leveling operations on Anacapa Island. Carrying elevation from bench mark up vertical cliff. Note steel tape. Level party of Lorne G. Taylor

Leveling operations on Anacapa Island. Carrying elevation from bench mark up vertical cliff. Note steel tape and lighthouse in background. Level party of Lorne G. Taylor

Leveling operations at the White House. Level party of Howard Rappleye

Teaching Liberians precise leveling techniques. Party of George Morris

Mechanized level crew moving up. Level party of Emerson E. Jones

Rodman in the Louisiana mud.

Ferdinand Hassler directing movement of the Great Theodolite on Fire Island. Angle measurements at the end points of the Fire Island Base Line. Probably sketched by Assistant John Farley

Packing to the top - Bill Scaife leading the way up. Triangulation party of William M. Scaife. Upper Cook Inlet to Fairbanks

Packing to the top - sheer fortitude kept him going. Triangulation party of William M. Scaife. Upper Cook Inlet to Fairbanks

On Northwestern Glacier. Off of WILDCAT. Combined operations party of Paul A. Smith

Climbing to a station. Off of WILDCAT. Combined operations party of Paul A. Smith

Climbing to a station - the level of difficulty has increased. Off of WILDCAT. Combined operations party of Paul A. Smith

Back packing party preparing to leave the ship. On their way to shore in a skiff. Photo sheet No. 1 of sequence

Underway and resting enroute. Off of EXPLORER. Photo sheet No. 2 of sequence

Stopping for lunch and a rest enroute. Off of EXPLORER. Photo sheet No. 3 of sequence

At the top. Off of EXPLORER. Photo sheet No. 4 of sequence

Survey crew going to Station Rail. Off of WESTDAHL

Mountain climbing (stumbling?) in the White Pass area. Off of WESTDAHL

William Musseter setting steel bars to facilitate climbing for observing party. Reconnaissance party of William Musseter

Station Emery near Muddy River. Triangulation party of Frank G. Johnson

Carrying lumber up rift in cliffs at east end of Amlia Island. Note boat at beach - shore party shows as barely visible specks at top of photo . Party off of PIONEER

Shoran navigation gear being brought ashore at Nushagak Bay. Party off of PATHFINDER

Shoran navigation gear being brought ashore at Nushagak Bay. Party off of PATHFINDER

Rest stop while climbing to station at Ragged Point.

Hauling Shoran gear up Cape Mountain.

Transporting survey gear on snowsled with tramway. Party of Lorne G. Taylor

Hauling gear on a whale bone sled.

Hauling gear on a whale bone sled. Party off of PATHFINDER

At the end of truck travel on the Olympic Peninsula. Reconnaissance party of John A. Webb

In climbing Gallatin Peak the horses took some bad rolls. Triangulation party of William M. Scaife

Traveling in style in the Big Bend. Triangulation party of Wilbur M. Porter

"Mut is down". Enroute to Scotch Cap Lighthouse. First horses in the Aleutians. Party off of DISCOVERER

Landing feed for the horses at Middle Point. South coast of Unimak Island. Party off of DISCOVERER

Horses packed with theodolite, tripod, and triangulation equipment. 5 miles west of Cape Lutke. Party off of DISCOVERER

A little blacksmith work on Unimak Island. Party off of DISCOVERER

H. C. Applequist and Mutt - riding the range on Unimak Island. Party off the GUIDE

Francis X. Popper riding the range on Unimak Island. Party off the GUIDE

Base camp at Mt. Como. Triangulation party of J. C. Sammons

Start of the trail at the end of the road. Heading into the Salmon River Canyon. Reconnaissance party of Oscar Risvold

Swimming the horses across the Salmon River. Reconnaissance party of Oscar Risvold

Along the trail in Salmon River Canyon. Reconnaissance party of Oscar Risvold

Not a good place for claustrophobia. Along the trail in Salmon River Canyon. Reconnaissance party of Oscar Risvold