kayakbird Posted November 1, 2010 Posted November 1, 2010 KL0592 This inscription was noticed on the Fairplay Colo Court House/Library about four feet above USGS H3. The elevation matches with the Hayden Survey Central Colorado map published in 1877. MAP A couple of questions: did the Hayden Survey place the mark? and why has no one mentioned it as a reference object? kayakbird Quote
holograph Posted November 1, 2010 Posted November 1, 2010 (edited) This inscription was noticed on the Fairplay Colo Court House/Library about four feet above USGS H3. The elevation matches with the Hayden Survey Central Colorado map published in 1877. MAP A couple of questions: did the Hayden Survey place the mark? and why has no one mentioned it as a reference object? kayakbird Is that paint underneath the "U.S."? Almost all of the King, Hayden, Powell, and Wheeler survey marks were made for mapping purposes, and were folded into the USGS in 1879 when all the Western Surveys were consolidated. Very few of them were considered accurate enough to be used by the Coast Survey and hence aren't in the NGS database. Wheeler published descriptions of some of his marks, and the USGS belatedly published the triangulation of Powell, but I haven't found sources for King or Hayden that contain descriptions of their marks. The best reference I've found so far has been Gannett's 1895 Bulletin No. 123 of the USGS, and that only contains the triangulation stations, not the bench marks. As a matter of interest, I spent some time trying to figure out the relationships between the surveys and what was surveyed by whom. Ultimately, I intend to make a wiki page from it. Here is a preliminary map that I made showing the surveys and the areas of overlap: Edited November 1, 2010 by holograph Quote
kayakbird Posted November 2, 2010 Author Posted November 2, 2010 George, Great map! I had heard of all those old surveys, but didn't know just what areas they covered. At Fairplay the U.S. is definitely chiseled with maybe some paint residue. 9964 ft may have been lightly scratched and painted latter, with Hayden just paint, and likely a different hand. To my eye the paint has retarded the erosion of the stone under Hayden and the elevation. kayakbird KL0592 Quote
holograph Posted November 2, 2010 Posted November 2, 2010 (edited) Great map! I had heard of all those old surveys, but didn't know just what areas they covered. At Fairplay the U.S. is definitely chiseled with maybe some paint residue. 9964 ft may have been lightly scratched and painted latter, with Hayden just paint, and likely a different hand. To my eye the paint has retarded the erosion of the stone under Hayden and the elevation. kayakbird The USGS Miscellaneous Publication #1, 1875, pg. 14, states that the elevation at Fairplay (9964 ft.) was determined by a railway survey. Page 63 states that the 9964 ft. elevation was at the "Doorsill of Sentinel office before fire of 1873". I suspect that the elevation on the side of the courthouse was informal, and was simply painted there for public information. Edited November 2, 2010 by holograph Quote
foxtrot_xray Posted November 2, 2010 Posted November 2, 2010 Great map! I had heard of all those old surveys, but didn't know just what areas they covered. At Fairplay the U.S. is definitely chiseled with maybe some paint residue. 9964 ft may have been lightly scratched and painted latter, with Hayden just paint, and likely a different hand. To my eye the paint has retarded the erosion of the stone under Hayden and the elevation. kayakbird The USGS Miscellaneous Publication #1, 1875, pg. 14, states that the elevation at Fairplay (9964 ft.) was determined by a railway survey. Interesting document there, Holo. I like the two separate heights given for Pike's Peak: US Signal Service: 14,147 Parry (?): 14,216. --Me. Quote
kayakbird Posted November 3, 2010 Author Posted November 3, 2010 .... 9964 ft. elevation was at the "Doorsill of Sentinel office before fire of 1873". I suspect that the elevation on the side of the courthouse was informal, and was simply painted there for public information. George, That sounds logical. Court House was build in 1874 and Hayden map published in 1877. I doubt if they worried about +/- 0.50 FT like we do now. For clarification the "Page 63' link takes you to the Fourth Edition, published in 1877; where I found a couple of interesting tidbits: Capt Ludlow's elevations along the Carroll Trail Carroll Trail are in it and the St Louis Directrix is give as 428.29 feet MSL, 13.5 feet higher than the 1912 published elevation. St Louis Directrix Since many of the Railroad elevations seem to be tied to St Louis and many surveys tied to a RR mark, that leaves lots of room for discrepancies. kayakbird Quote
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