Although the Monument was completed in 1884, it appears that it did not make it into the Goast & Geodetic Survey's 'database' for surveying purposes until 1913.This is an example of an intersection station - the point intersected being the pinnacle of the Monument.
In 1999, during repairs on the monument, the National Geodetic Survey took the opportunity to conduct GPS observations from the top of the monument while it was accesible - (
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Also see the following for a map of other marks used in the project - (
visit link)
The Actual recovery information from the NGS datasheet is as follows:
1/1/1913 by CGS (FIRST OBSERVED)
DESCRIBED BY COAST AND GEODETIC SURVEY 1913 (OBF) STATION IS CENTER OF TIP OF WASHINGTON MONUMENT.
1/1/1927 by CGS (GOOD)
RECOVERY NOTE BY COAST AND GEODETIC SURVEY 1927 (BW) STATION WAS RECOVERED.
1/1/1928 by CGS (GOOD)
RECOVERY NOTE BY COAST AND GEODETIC SURVEY 1928 (EOH) THIS STATION IS CENTER OF THE TIP OF THE WASHINGTON MONUMENT.
1/1/1934 by CGS (GOOD)
RECOVERY NOTE BY COAST AND GEODETIC SURVEY 1934 (JB) THE STATION IS THE APEX OF THE WASHINGTON MONUMENT, AND IS MARKED BY THE CENTER OF THE ALUMINUM TIP THAT SURMOUNTS THE MONUMENT. THIS TIP HAS APPARENTLY BEEN BURNED BY LIGHTNING, AS THE TOP IS ABOUT 1/2 INCH SQUARE. THE STATION WAS OCCUPIED DURING THE COURSE OF WASHING AND REPAIRING THE MONUMENT, AND THE SCAFFOLDING ERECTED FOR THAT PURPOSE WAS USED TO REACH THE TOP. NO REFERENCES ARE NECESSARY.
1/1/1946 by CGS (GOOD)
RECOVERY NOTE BY COAST AND GEODETIC SURVEY 1946 (RCB) THE STATION WAS RECOVERED AS DESCRIBED, BUT WAS NOT OCCUPIED. A COMPLETE NEW DESCRIPTION FOLLOWS--THE POINT OBSERVED UPON WAS THE APEX OF THE ALUMINUM CAP AT THE TOP OF THE MONUMENT.
1/1/1959 by CGS (GOOD)
RECOVERY NOTE BY COAST AND GEODETIC SURVEY 1959 (JKR) THIS INTERSECTION STATION WAS RECOVERED AS DESCRIBED.
1/1/1961 by CGS (GOOD)
RECOVERY NOTE BY COAST AND GEODETIC SURVEY 1961 (JPP) THIS STATION RECOVERED AS DESCRIBED AND WAS FOUND TO BE IN GOOD CONDITION.
1/1/1965 by CGS (GOOD)
RECOVERY NOTE BY COAST AND GEODETIC SURVEY 1965 (DCW) STATION RECOVERED AS DESCRIBED.
1/1/1976 by NGS (GOOD)
RECOVERY NOTE BY NATIONAL GEODETIC SURVEY 1976 (AMS) STATION RECOVERED AS DESCRIBED AND IN GREAT CONDITION. AIRLINE DISTANCE AND DIRECTION FROM NEAREST TOWN IN D.C.
1/1/1979 by NGS (GOOD)
RECOVERY NOTE BY NATIONAL GEODETIC SURVEY 1979 (BMP) THE STATION WAS OBSERVED APPARENTLY AS PREVIOUSLY DESCRIBED.
1/1/1979 by NGS (GOOD)
RECOVERY NOTE BY NATIONAL GEODETIC SURVEY 1979 (MWJ) STATION RECOVERED AS DESCRIBED.
1/1/1983 by NGS (GOOD)
RECOVERY NOTE BY NATIONAL GEODETIC SURVEY 1983 (DAH) RECOVERED AS DESCRIBED, STILL IN GREAT CONDITION. AIRLINE DISTANCE AND DIRECTION FROM NEAREST TOWN--IN WASHINGTON.
6/19/1995 by USPSQD (GOOD)
RECOVERY NOTE BY US POWER SQUADRON 1995 RECOVERED IN GOOD CONDITION.