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Details for Benchmark: MY0556

N 42° 21.517 W 071° 03.200 (NAD 83)

Altitude: 11.11

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

Location:
In SUFFOLK county, MA View Original Datasheet
Designation:
844 3970 TIDAL 15
Marker Type:
tidal station disk
Setting:
in rock outcrop
Stability:
Most reliable and expected to hold position/elevation well.

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First benchmark we found in Boston today. All good.

[Photos:]
photoDisk

Found while out for an afternoon walk

[Photos:]
photoMY0556
Closeup
photo
Location

Found while on Break this morning

[Photos:]
photoMY0556

Found it!

[Photos:]
photoMY0556 close
photoMY0556 distance

Seen it during my stay in Boston.

TFTB

[Photos:]
photoMY0556.

We found it easily thanks to notes from others.

[Photos:]
phototidal 15

Found this while wandering the streets after dark

[Photos:]
photoIMG_4188

The fifth benchmark find for Bigrock95 and me in Boston this afternoon. Nice to revisit some of these downtown locales that I haven't been to in a long time and then spend time looking down at all the marks on the concrete. As Rocky wrote, we sure looked odd taking our closeup pictures (or at least he did ).

[Photos:]
photoMY0556 (stamped NO. 15 1950) disk
photoNO. 15 with my 60 CSx
photoSide of the Custom House showing MY0556

Recovered in good condition. Passing pedestrians were certainly curious as to what OleSeeker and I were doing but never asked. They just thought it odd that we were taking photos of the concrete... little did they know the wonders of benchmarking.

[Photos:]
photoMY0556-844_3970_TIDAL_15-1-20120205
photoMY0556-844_3970_TIDAL_15-20120205-Oregon_550t
blank screen-batteries died and spares were in the car
photoMY0556-844_3970_TIDAL_15-3W-20120205

Biked into Boston after work to find a few benchmarks downtown. A demonstration was just getting going one block away. Previous finders' pictures were helpful in locating the mark.

[Photos:]
photoNO 15
photoArrow indicates location of benchmark

done!

[Photos:]
photoNO 15

We wanted a tidal from Boston, and found this one without any problem at all.

The mark is in good condition.

[Photos:]
photoMY0556(844 3970 TIDAL 15) - Boston MA
photoMY0556 - Looking N toward mark
photoMY0556 - Looking E on Central St.
photoMY0556 - Looking W on Central St.

Found with ease in location stated.

[Photos:]
photoMY0556

found in good condition

[Photos:]
photoCustom House Tidal Mark 15

Woohoo! Found while wandering around Boston.

[Photos:]
photoThe benchmark

Recovered in good condition.

[Photos:]
photoPhoto

Found as described. It hasn't moved since the last observation.

[Photos:]
photoDisk 844 3970 Tidal 15 - Close Up
photoDisk 844 3970 Tidal 15 - Face of building and st.

An easy find from the given description, but my GPS has a better time in my living room than in this area.

[Photos:]
photoThe Benchmark
This is it. It reads NO 15 1950.
photoThe tower
Any Bostonian or visitor to the city should instantly recognize this building.

This building is now a Marriott. The mark is easy to find, although my GPS didn't work well in the city and I only had handwritten notes from the description.

[Photos:]
photo844 3970 TIDAL 15 MY0556 Boston, MA
photo844 3970 TIDAL 15 MY0556 Boston, MA

Way to nice of a day not to go for a walk during lunch with a mission to find some benchmarks. This is one of three I found today.

Documented History (by the NGS)

01/01/1950 by CGS (MONUMENTED)
01/01/1965 by NGS (GOOD)
DESCRIBED BY NATIONAL GEODETIC SURVEY 1965 AT BOSTON. AT BOSTON, AT THE INTERSECTION OF INDIA AND CENTRAL STREET AT THE U.S. CUSTOM HOUSE, SET IN THE TOP OF A GRANITE LEDGE ALONG THE SOUTH SIDE OF THE BUILDING, 21.0 FEET EAST OF THE CENTER OF THE SOUTH ENTRANCE OF THE BUILDING, 6.9 FEET NORTH OF THE NORTH CURB OF CENTRAL STREET AND ABOUT 2 FEET ABOVE THE LEVEL OF THE STREET.
01/01/1978 by NGS (GOOD)
RECOVERY NOTE BY NATIONAL GEODETIC SURVEY 1978 THIS BENCH MARK HAS BEEN DESIGNATED A BASIC NET A LEVEL LINE JUNCTION MARK.

Control Text

  • 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.
  • This Tidal Bench Mark is designated as VM 186 by the Center for Operational Oceanographic Products and Services.
  • 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. The observed gravity was obtained from relative gravimeter ties to the IGSN71 gravity network.

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