A completed Bilby tower on the North Carolina State University campus at Raleigh . The observing truck is a Graham Brothers truck which was called either a dog- catcher truck or post office truck. This truck company was bought by Dodge.

Ben Hickok on the light-keeper's perch on a Bilby tower at North Carolina State University.

Ben Hickok standing about 90-feet above the ground. Safety lines weren't required in those days. Ben was wearing his ROTC uniform.

Ben Hickok showing his best hole digging form for placing marks. Marks were set in pre-cast concrete monuments that were 4-feet in length in order to get below the frost line and not be subject to heaving in cold weather. Monuments were tapered and set with large end in the ground. Each monument weighed 200 pounds.

Preparing to set a pre-cast concrete monument. Eddie Lyons on the left and Francis Dillon on the right. Both were from Massachusetts.

Francis Dillon Preparing to set a pre-cast concrete monument near Alma.

Ben Hickok painting arrows in center of tracks pointing to bench marks set off railroad, but still on the railroad right-of-way.

Ben Hickok tamping in a monument. Note the top of the concrete monument protruding about 4 inches above the surface. Ford pickup truck to right has additional monuments laying in bed. Note round disks in top of concrete monuments. These are C&GS bronze level marks.

Tommy Garey from Washington, D.C., sitting on the bumper of a brand new Dodge Brothers truck. Taken on a Sunday. Dressed up to go to church.

Eddie Lyons digging a hole to set a mark. In this area the soil was sand and gravel so a hole could be dug in about 15 minutes. The hole had to be made larger than the monument because the sand would keep caving in.

Mark setter's truck, No. 242, nicknamed "Black Maria" as it was similar to a police paddy-wagon which were given that name in the 1930's. Bench mark crew members would ride on benches in back during moves. Headaches were common for the crew after a long move as exhaust fumes would fill the back end. Back end couldn't be closed because of level rod box.

Ben Hickok in the new Dodge Brothers truck.

Bill Chisom, rodman; George Hastings, the observer and party chief; and Bill Unger rodman. This was a posed Sunday photo as suits weren't worn to work.

Guntersville downtown near the Guntersville Dam near the Tennessee border on the Tennessee River. Note the mode of transportation. Saturday afternoon. The poor cow was rope-sprung, a term for a broken down swaybacked animal.

George Hastings observing in an Alabama cornfield.

George Hastings observing levels; "Smitty" Smith holding umbrella; and Bill Unger (?) gun-toter. The umbrella was used to keep the sun off the level bubble on the leveling instrument as that would draw the instrument out of level and make erroneous readings.

Level crew tempting fate along a railroad northeast of Decatur.

Leveling operations in heavy brush.

Pilothouse of a Tennessee River ferry boat. The boat would accommodate 4 4 to 6 vehicles depending on size. This boat had a 1-cylinder gasoline engine.

Ben Hickok and Bill Unger riding the Alabama, a Tennessee River ferry boat. The boat would accommodate 4 to 6 vehicles depending on size and had a 1-cylinder gasoline engine.

The mighty Alabama, a stern-wheel Tennessee River ferry boat.

Observing three-point sextant fix while surveying the reservoir of the Grand Coulee Dam.

Reading depths off fathometer on the left and recording depths in field record book on right.

Reading temperatures to determine sound velocity for correcting fathometer readings.

Portable fathometer transducer being lowered into water.

Reading temperatures to determine sound velocity for correcting fathometer readings.

Reading depths off fathometer on the left and recording depths in field record book on right.

All systems go! Taking three point sextant fix while on-line. Recorder by clock. Fathometer operator in bottom left out of picture. Officer in charge plotting fixes with three-arm protractor on table forward.

Living quarters for the field party while surveying the Grand Coulee Dam reservoir.

Hard hat diver cutting cable from propeller of Coast and Geodetic Survey Ship LYDONIA.

Appears to be Texas Tower #4 south of Woods Hole. This tower was lost on January 15, 1961, during a storm with a loss of 28 lives. Ship was probably using tower as a fixed point to calibrate electronic navigation system.

Appears to be Texas Tower #4 south of Woods Hole. This tower was lost on January 15, 1961, during a storm with a loss of 28 lives. Ship was probably using tower as a fixed point to calibrate electronic navigation system.

Hydrographic signal on the shores of the reservoir of Grand Coulee Dam. Used as signal for navigation by three-point sextant fix.

VAM-2 Magnetometer installed in Navy R5D aircraft. L to R, , Mr. Robert Seaton of Navy Hydrographic Office, and L. Hurwitz, LCDR David Whipp, R. Gebhardt, Joel Campbell, and J. Bottum, all of the USC&GS.