@mark-silver?ÿ ?ÿ ?ÿ ?ÿI like your post above on what you call 3 corners but I do have several things about it.
You show 1,285.65 meters then (4218.0?ÿ sFt) where the s is for survey feet. At this short distance and to the accuracy you show
(0.1 feet) it does not matter which foot you use. 1,285.65 meters = 4218.0 init. feet and = 4218.0 sFt.
The next thing is in the next to last par. "evidenced by a 4,200 bust"?ÿ I guess you just left out the sFt or iFt?
Thanks again for the informative post.
?ÿ
JOHN NOLTON
And here's the snippet from the NGS Data Explorer Satellite View. The superseded coordinates on the data sheet match the ones in Publication 209, 41 00 02.616N, 109 02 57.633W.?ÿ
Yet another hijack...
While one might wish that some things remain permanent and definitive, there is always change, better understanding.
On a 2005 visit to London, I made it a point to visit Greenwich. Placing my Garmin Etrex on the meridian line, I noted a 5.4 second discrepancy from the expected longitude of 0d 0m 0s. See picture below. I forget why the time stamp is wrong. This visit was 5-12 December 2005.?ÿ
The explanation is here: https://www.rmg.co.uk/discover/explore/prime-meridian-greenwich ?ÿ
Like the points mentioned in this thread (or the mile high markers (plural) in Denver, CO, the Mason-Dixon Line markers, etc) better understanding/techniques/points of reference make them nice destinations to visit and historical but unreliable as definitive markers of what they purport to be.
?ÿ ?ÿ?ÿ
We can get close to the longitude published on the sign from this old publication:
On page 38, we're told that the adopted longitude of the Naval Observatory in 1863 is 5 hours, 8 minutes, 11.0 seconds west of Greenwich. The longitude in degrees, minutes and seconds is: (5 + 8/60 + 11/3600) / 24 * 360 = 77.04583333 degrees = 77 02 45.
The point is defined to lie on the 32nd meridian west of Washington, DC, so its longitude would be 77 02 45 + 32 00 00 = 109 02 45 versus 109 02 42.158 on the sign.
Later determinations of the Naval Observatory's position put it further west, but we need for it to be further east.?ÿ
It does look as though the location on the sign is not NAD 27. Tracking down that exact longitude might prove difficult, but it didn't take a lot of effort to get close.
Thanks for sharing it!
?ÿ
YES...32?ø West of Washington!
I went back and looked at USGS PP 909, and I was looking at the wrong line in the paragraph (page 141)!
25?ø West of Washington was the EAST Line of Colorado (Man I'm really losing it).
???
Well, the first time I looked at it, I used 34 degrees, the west side of Utah.
The boundaries of the Utah Territory have varied a great deal over time:
See USGS PP-909
https://pubs.er.usgs.gov/publication/pp909
Here's a clip of FIGURE 45 (page 160)
?ÿ
Yes, I was using the present statutory boundaries. That 34th meridian seems to have been difficult to pin down.
Of course at latitude 51d 28m 38s a difference of 5.4s is over 104 meters.?ÿ
Here's a link to a thread concerning the 41?ø North 34?ø West Monument
https://surveyorconnect.com/community/surveying-geomatics/testing-new-gnss-receiver-yesterday/
