Details for Benchmark: LY0630
N 41° 21.783 W 074° 41.083 (NAD 83)
Coordinates may not be exact. Altitude is ADJUSTED and location is SCALED. (more info)
- In ORANGE county, NY View Original Datasheet
- Marker Type:
- bench mark disk
- massive structures
- Probably hold position/elevation well.
Benchmarks may be on private property or in dangerous locations. Obey local laws. By using the services on Geocaching.com you agree to this disclaimer.
Documented History (by the NGS)
|01/01/1900 by USGS (MONUMENTED)
|01/01/1941 by NGS (GOOD)
|DESCRIBED BY NATIONAL GEODETIC SURVEY 1941
AT PORT JARVIS. AT PORT JERVIS, ORANGE COUNTY, ABOUT 0.8 MILE SOUTHEAST ALONG THE ERIE RAILROAD FROM THE STATION, ABOUT 0.5 MILE SOUTHEAST OF MILEPOST 87, AT BRIDGE 86.52 OVER EAST MAIN STREET, AT THE SOUTHWEST CORNER OF THE SOUTHEAST ABUTMENT, IN THE WEST CORNER OF THE FIRST STEP BELOW THE BRIDGE SEAT, 24.2 FEET EAST OF THE CENTER LINE OF THE STREET, AND 9.8 FEET SOUTHWEST OF THE SOUTHWEST RAIL OF THE SOUTHWEST MAIN TRACK. A UNITED STATES GEOLOGICAL SURVEY STANDARD DISK, STAMPED 456 ALBANY 1900.
- The horizontal coordinates were scaled from a topographic map and have an estimated accuracy of +/- 6 seconds.
- The orthometric height was determined by differential leveling and adjusted by the National Geodetic Survey in June 1991.
- The geoid height was determined by GEOID99.
- The dynamic height is computed by dividing the NAVD 88 geopotential number by the normal gravity value computed on the Geodetic Reference System of 1980 (GRS 80) ellipsoid at 45 degrees latitude (g = 980.6199 gals.).
- The modeled gravity was interpolated from observed gravity values.