Signal built on tree at Station WADE. Party off of HYDROGRAPHER

Signal at Isle Chandeleur. Party off of BACHE

Completed 100-foot signal. Note man at top. Party off of HYDROGRAPHER

Station Mud - built in 12 feet of water and no telling how much mud. Party off of Launch ELSIE III

Building a 100-foot tall hydrographic signal

A completed hydrographic signal. Multiple colors for identification from offshore. Signal for OCEANOGRAPHER operations

Building a large hydrographic signal. Multiple colors for identification from offshore. Party off of OCEANOGRAPHER

On top of Station PERP. Party off of EXPLORER

Large hydrographic signal. Photograph in 1931 Hydrographic Manual

Building a tri-pod type signal. Photograph in 1931 Hydrographic Manual

Hydrographic signal as seen from sea

A pole signal at Station Clarence Astro. Party off of EXPLORER

Tripod signal on south coast of American Samoa. Built by party off of SURVEYOR

Station Pic at west end of Picara Point. Building party off of WHITING

Station Pic at west end of Picara Point. Building party off of WHITING

Building signal at Station Out. Building party off of WHITING

The way to Station Can. Building party off of WHITING

Signal and navigation trisponder at Station Can. Installation by party off of WHITING

Signal and navigation trisponder at Station Can. Installation by party off of WHITING

Station Hans at south end of Hans Lollik Island. Building party off of WHITING. Note century plants and desert aspect of island

Triangular hydro signal. Building party off of PATHFINDER

Hydro signal being built for calibration of Raydist system. Building party off of NOAA Launch 1257. Glenn Hendrix kneeling, Steve Lloyd standing

Signal building party off of PEIRCE

Large tripod signal being built. Building party off of PEIRCE

Signal building party in Southeast Alaska. Party off of PATHFINDER

Signal in Prince William Sound

Signal in Prince William Sound

Signal in Penobscot Bay. Signal built by party off of PEIRCE

Dismantling the signal at Station Out, Thatch Cay. Cleaning up at the end of a project. Lt.(j.g.) Mike Kuhl cutting wire securing signal

Flags on bell and whistle buoys. Using harbor buoys for signals for survey work off the BACHE. Black flags showed up best

Planting a survey signal buoy. Off LYDONIA or NATOMA

Constructing a floating buoy signal. Buoy in place. For use by East Coast wiredrag party

Signal off the Delaware coast. Planted by RANGER

A floating signal. Photograph in 1931 Hydrographic Manual

Floating signal off the Delaware coast. Party off of RANGER

Tautwire measuring machine. By trailing wire astern and counting revolutions, one can determine distances. Used to measure distance between floating hydrographic signals

White-washed hydrographic signals in Taku Inlet area. Who says engineers can't be artistic? Signal made by crew off of WESTDAHL

ORCA signal in Taku Inlet. Told tourists in area that signals were native hieroglyphics. Signal made by crew off of WESTDAHL

White-washing hydrographic signals in Alaska.

Signal party white-washing rock. Party off of EXPLORER

White-washing rock. Party off of LESTER JONES

Preparing white-wash for marking signal. At Station ACT on Amchitka Island. Party off of EXPLORER

Taking sextant angles for positioning vessel.

Working together for a three-point sextant fix. Note horizontal attitude of sextants

Calibrating Raydist by using three-point sextant fix. Initial tests of Raydist off of SOSBEE

Launch hydrography three-point sextant fix. Surveying lagoon at Kwajalein Island. Party off of PIONEER

Launch hydrography three-point sextant fix. Surveying in vicinity of Kalgin Island. Party off of SURVEYOR

Wharton and Jeffries taking three-point sextant fix. Surveying in vicinity of Kalgin Island. On SURVEYOR

Taking three-point sextant fix with check angle. Calibrating electronic navigation system. Third man searching for signal. On NOAA Launch 1255

Taking three-point sextant fix with check angle. Calibrating electronic navigation system. On NOAA Launch 1255