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Newbie to BM -Question on marker type: lighthouse


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We're goin' up North this year (Michigan UP), and I've been looking for benchmarks at/near some lighthouses we'll be visiting. this benchmark just says 'lighthouse' for type. All the other benchmarks I looked up had more or less detailed locations, and what type of marker. When we find the lighthouse, can I then claim a find on the BM since nothing else was listed? Is there a definate physical marker at this site besides the entire lighthouse itself that I'm overlooking??

 

Thanks!

 

Thanks!

 

I walk the Maze of Moments, but everywhere I turn to, begins a new beginning, but never finds a finish... -Enya, Anywhere Is

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The lighthouse is the mark. If you see the lighthouse, you've found this benchmark.

 

I think especially back in the 1930s and 1940s, a lot of tall buildings were used as the mark. It was certainly easier than putting a brass disk somewhere.

 

Around here I have church spires, smokestacks, water tanks and cupolas as benchmarks...

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Its true that objects were more commonly used in the past, but it was not really because they were easier. It was because, unlike ground points, they can be seen from great distances without setting up a target, since the object is itself a target, having the appearance of a needle, when observed from afar. So they are really a very different type of point.

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Its still there. I was working on a project for MDOT and we found it. Its a popular tourist attraction.

 

quote:

 

 

The NGS Data SheetSee file dsdata.txt for more information about the datasheet.DATABASE = Sybase ,PROGRAM = datasheet, VERSION = 6.73

1 National Geodetic Survey, Retrieval Date = MARCH 27, 2003

SG0161 ***********************************************************************

SG0161 DESIGNATION - EAGLE HARBOR LH MIGS

SG0161 PID - SG0161

SG0161 STATE/COUNTY- MI/KEWEENAW

SG0161 USGS QUAD - EAGLE HARBOR (1975)

SG0161

SG0161 *CURRENT SURVEY CONTROL

SG0161 ___________________________________________________________________

SG0161* NAD 83(1994)- 47 27 34.82951(N) 088 09 33.12729(W) ADJUSTED

SG0161* NAVD 88 - 408. (meters) 1339. (feet) SCALED

SG0161 ___________________________________________________________________

SG0161 LAPLACE CORR- -5.19 (seconds) DEFLEC99

SG0161 GEOID HEIGHT- -34.84 (meters) GEOID99

SG0161

SG0161 HORZ ORDER - THIRD

SG0161

SG0161.The horizontal coordinates were established by classical geodetic methods

SG0161.and adjusted by the National Geodetic Survey in February 1997.

SG0161

SG0161.The orthometric height was scaled from a topographic map.

SG0161

SG0161.The Laplace correction was computed from DEFLEC99 derived deflections.

SG0161

SG0161.The geoid height was determined by GEOID99.

SG0161

SG0161; North East Units Scale Converg.

SG0161;SPC MI N - 298,123.553 7,912,587.901 MT 1.00011377 -0 50 16.3

SG0161;UTM 16 - 5,256,899.419 412,630.195 MT 0.99969381 -0 51 15.0

SG0161

SG0161: Primary Azimuth Mark Grid Az

SG0161:SPC MI N - WEST BLUFF 2 088 39 30.7

SG0161:UTM 16 - WEST BLUFF 2 088 40 29.4

SG0161

SG0161|---------------------------------------------------------------------|

SG0161| PID Reference Object Distance Geod. Az |

SG0161| dddmmss.s |

SG0161| TY7767 WEST BLUFF 2 APPROX.14.4 KM 0874914.4 |

SG0161|---------------------------------------------------------------------|

SG0161

SG0161 SUPERSEDED SURVEY CONTROL

SG0161

SG0161 NAD 83(1986)- 47 27 34.81835(N) 088 09 33.09922(W) AD( ) 3

SG0161 NAD 27 - 47 27 35.13000(N) 088 09 32.70200(W) AD( ) 3

SG0161

SG0161.Superseded values are not recommended for survey control.

SG0161.NGS no longer adjusts projects to the NAD 27 or NGVD 29 datums.

SG0161.See file dsdata.txt to determine how the superseded data were derived.

SG0161

SG0161_U.S. NATIONAL GRID SPATIAL ADDRESS: 16TDT1263056899(NAD 83)

SG0161_MARKER: 13 = LIGHTHOUSE

SG0161_SATELLITE: THE SITE LOCATION WAS REPORTED AS NOT SUITABLE FOR

SG0161+SATELLITE: SATELLITE OBSERVATIONS - September 04, 2000

SG0161

SG0161 HISTORY - Date Condition Report By

SG0161 HISTORY - 1934 FIRST OBSERVED MIGS

SG0161 HISTORY - 20000904 GOOD MIDT

SG0161

SG0161 STATION DESCRIPTION

SG0161

SG0161'DESCRIBED BY MICHIGAN DEPARTMENT OF TRANSPORTATION 2000 (MPR)

SG0161'THE LIGHTHOUSE IS A HISTORICAL LANDMARK AND POPULAR TOURIST

SG0161'ATTRACTION. IT IS LOCATED IN EAGLE HARBOR JUST OFF STATE HIGHWAY

SG0161'M-26, THE LIGHT IS OPERATIONAL.

 

*** retrieval complete.

Elapsed Time = 00:00:01

 


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