Skip to Content

Details for Benchmark: OC2186

N 43° 02.587 W 070° 42.754 (NAD 83)

Altitude: 10

Coordinates may not be exact. Altitude is SCALED and location is ADJUSTED. (more info)

Location:
In ROCKINGHAM county, NH View Original Datasheet
Designation:
PORTSMOUTH HARBOR SE BASE 1842
Marker Type:
drill hole
Setting:
in a boulder
Stability:
May hold, but of type commonly subject to surface motion.

Reference Points

Must Read!

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.

Thanks!

[Photos:]
photoIMG_4180

Found while in the area caching.

[Photos:]
photoOC2186

Had to climb the rock to get a picture.

[Photos:]
photoOC2186

The only one of the three we actually found on a beautiful Mother's Day!

[Photos:]
photoDrill mark

Rare to see such an historic disk with no stamping

late log 7/14/12: found while enjoying the views! easy find, mark in fair condition

[Photos:]
photoN43 02.588 W070 42.753
photolooking WNW at boulder with disk
N 43° 02.588 W 070° 42.751

Found in good condition with FiddlingFox & ForesterCat. Mark is scratched/dented from vandalism, but otherwise useable. My coordinates and photos posted.

[Photos:]
photo1842 close-up
photo1842 eye-level view
View to northwest of bencmark location, FiddlingFox pointing to mark.
photo1842 area-view
View to southwest of 1842 benchmark location. FiddlingFox pointing to location of mark.

Saw this disk from afar while Jay-7 trampled thru Rosa Rugosa and got bm battlewounds.

Found this triangulation station disk in a good condition while strolling around Odiorne Point State Park. I have seen a lot of bench mark disks but never a disk with such a tiny stamping which is C&G. I have searched a good time for the reference mark but couldn't find it.
King Hubi

[Photos:]
photoOC2186 - PORTSMOUTH HARBOR SE BASE 1842 [closeup]
Closeup, stamping is C&G
photoOC2186 - PORTSMOUTH HARBOR SE BASE 1842 [with GPS]
Closeup with GPS, HH2 coordinates are N43°02.588' W070°42.754'
photoOC2186 - PORTSMOUTH HARBOR SE BASE 1842 [in rock]
Sitting at the highest point of a large rock
photoOC2186 - PORTSMOUTH HARBOR SE BASE 1842 [west]
Facing west with playground in the background
photoOC2186 - PORTSMOUTH HARBOR SE BASE 1842 [east]
Facing east to the ocean
photoOC2186 - PORTSMOUTH HARBOR SE BASE 1842 [area]
Area view facing west, in the top of a large rock

CSI Team found Benchmark at 16:37 hrs.

Recovered in good condition.

[Photos:]
photoOC2186_PORTSMOUTH HARBOR SE BASE 1842

Walked up to it. Easy find.

Found it.®

Found by description.

[Photos:]
photoOC2186 Rockingham NH Close Up
photoOC2186 Rockingham NH View NW

Found this on a trip to Portsmouth.

[Photos:]
photothe mark
photothe area

Found with modification to the description. Fort Dearborn is now the Ordiornes Point State Park. To reach the station from the south end of the park's main parking area, walk easterly on a paved path for about 400 feet. Follow the path as it bends from east to south and continue for 200 feet to a paved path leading to a small picnic area on the right. Walk west for 70 feet to the large boulder and the station.

[Photos:]
photoOC2186 - the Mark
photoOC2186 in Rockingham Co., NH
Looking northwest.

Documented History (by the NGS)

01/01/1842 by CGS (MONUMENTED)
01/01/1912 by CGS (SEE DESCRIPTION)
DESCRIBED BY COAST AND GEODETIC SURVEY 1912 STATION IS ON A LARGE ROCK, 6 FEET HIGH, NE OF C.F. EASTMANS HOUSE, THE STATION IN 1898 WAS MARKED BY A DRILL HOLE IN THE HIGHEST POINT OF THE ROCK. IN 1912 A STANDARD U.S.C. AND G.S. DISK STATION MARK WAS PLACED IN THE HOLE AND SURROUNDED BY LEAD. THE HOLE WAS 2 INCHES IN DIAMETER AND 5 INCHES DEEP. A STANDARD DISK WITNESS MARK IS SET IN STONE 28.74 METERS FROM THE STATION, IN AZIMUTH 208 DEG 37 MIN. A CROSS CUT IN THE BARN FOUNDATION IS 10.50 METERS FROM THE STATION, IN AZIMUTH 18 DEG 39 MIN. THE NW CORNER OF THE BARN IS 10.48 METERS AND THE NE CORNER 14.14 METERS FROM THE STATION.
01/01/1928 by CGS (GOOD)
RECOVERY NOTE BY COAST AND GEODETIC SURVEY 1928 (GCM) STATION RECOVERED AS DESCRIBED. TABLET EXTENDS FREE 1/2 INCH ABOVE ROCK AND MAY BECOME LOOSE BEFORE LONG. EASTMANS HOUSE IS GONE. A NEW HOUSE WHOSE WINGS PARTIALLY SURROUND THE ROCK AT A DISTANCE OF 2 METERS HAS BEEN BUILT BY DR. GRAVES OF CONCORD.
01/01/1943 by CGS (GOOD)
RECOVERY NOTE BY COAST AND GEODETIC SURVEY 1943 (FLG) RECOVERED AS DESCRIBED IN GOOD CONDITION EXCEPT FOR THE FOLLOWING DISCREPANCIES-- 1. STATION IS ON LARGE ROCK 5 FEET HIGH, NOT 6 FEET HIGH. THE FOLLOWING SHOULD BE ADDED TO THE DESCRIPTION-- 1. REFERENCE MARK 1 IS NO LONGER VISIBLE FROM STATION BECAUSE OF NEW HOUSE WINGS THAT HAVE BEEN BUILT. 2. HOUSE IS NOW OCCUPIED BY U.S. ARMY.
01/01/1943 by CGS (GOOD)
RECOVERY NOTE BY COAST AND GEODETIC SURVEY 1943 (PLB) THE STATION MARK WAS RECOVERED IN GOOD CONDITION. THE ROCK IN WHICH IT IS SET IS TOO SMALL TO OCCUPY WITHOUT A 12-FOOT STAND, SO ANOTHER STATION WAS LOCATED NEARBY AND CALLED DEARBORN. THE WALL OF THE HOUSE NEAREST THE STATION IS STILL STANDING BUT THE REST OF THE HOUSE HAS BEEN TORN DOWN.
01/01/1953 by CGS (GOOD)
RECOVERY NOTE BY COAST AND GEODETIC SURVEY 1953 (PT) THE STATION AND THE REFERENCE MARK WERE RECOVERED IN GOOD CONDITION. THE DISTANCE TO THE REFERENCE MARK WAS MEASURED WITH A STEEL TAPE AND FOUND TO BE CORRECT. THE BARN FOUNDATION AND DR. GRAVES HOUSE HAVE BOTH BEEN DESTROYED. THE DESCRIPTION IS ADEQUATE WITH THE FOLLOWING EXCEPTIONS-- THE STATION IS LOCATED ON ODIORNES POINT, ON THE GROUNDS OF FORT DEARBORN, ABOUT 0.2 MI. E OF THE MOST S GATE TO THE FORT, 106 FT. NW OF THE CENTER OF THE MOST N OF THREE GUN EMPLACEMENTS, 87 FT. SE OF THE S ONE OF TWO STONE FENCE POSTS, AND 61 FT. E OF A ROCK FENCE. THE STATION MARK IS STAMPED C AND G AND IS SET IN A ROCK AS PREVIOUSLY DESCRIBED. THE REFERENCE MARK IS NE OF THE STATION, SET IN A ROCK OUTCROP AND IS NOT STAMPED.

Control Text

  • The horizontal coordinates were established by classical geodetic methods and adjusted by the National Geodetic Survey in May 1998.
  • The orthometric height was scaled from a topographic map.
  • The Laplace correction was computed from DEFLEC99 derived deflections.
  • The geoid height was determined by GEOID99.

Advertising with Us

Return to the Top of the Page