+JeremyA Posted August 17, 2003 Share Posted August 17, 2003 Hi, I am a total newbie so please forgive the silly question. As I live in downtown Memphis I have started by trying to see the many benchmarks that are within a couple of miles of me. The nearest benchmark to my apartment is FF1997, however the designation of this benchmark is confusing - Memphis Columbus Twr Flagpole. The reason I am confused is that there is no Columbus Tower that I know of in downtown Memphis. However, the co-ordinates given point to the Lincoln American Tower, a building that I can see from my apartment window and which has a very prominent flagpole. This building was built in 1924 and the benchmark was first observed in 1929. Also, when first built this building was called the Columbian Mutual Life Tower and was the tallest building in Memphis (and therefore ideal as a benchmark?). I am fairly confident that this is the correct building so my questions are 1) should I log it as a find? and 2) should the incorrect designation be reported to the NGS? thanks, Jeremy A Quote Link to comment
BeachBum22 Posted August 17, 2003 Share Posted August 17, 2003 quote:I am a total newbie so please forgive the silly question. As I live in downtown Memphis I have started by trying to see the many benchmarks that are within a couple of miles of me. The nearest benchmark to my apartment is FF1997, however the designation of this benchmark is confusing - Memphis Columbus Twr Flagpole. I'm a one week old newbie, but when it comes to buildings, water towers, radio towers, church towers, etc. there is no little metal disc that has a number on it to absolutely verify that it's what was written up, in this case, in 1929. A lot of the building markers (actual discs) that I have found (in the wall of a building) are not the same building as originally described, i.e., Willies Metal Works is not Debbies Tuxedo Rentals, but the marker and building are still there. Since you don't have the luxury of a stamping on a disc, and the building now may have a different name, about the only way you could really verify it, I would think, is by doing some research at the library or in the county building records if there is such a thing. We still have 699,998 to go, so save that one for later - go dig up somebodys lawn and find a disc with numbers on it Quote Link to comment
+raouljan Posted August 17, 2003 Share Posted August 17, 2003 Boy ... that was the emptiest data sheet I have ever seen. I am going to make a guess that the Columbus and Columbian difference was a typo. You will notice that the marker is "62 = Flagpole" .. so the benchmark is the flagpole Sould you log the find? How close did you get to the flagpole? Should you notify NGS of the designation change? Well there are no recovery notes since the "First Observed" in 1929. I am suprised that the Power Squadron has not recovered that yet! My guess is that everyone in the area that uses that control knows it. If you are dead sure that it is the same pole, I think a recovery note giving the correct name of the building would not be outrageous. Besure to search the board for what "recovery" really means and how to file a recovery note. >Personally Responsible for the Recovery of .00244% of the Benchmark Database!<--watch this number! Quote Link to comment
+JeremyA Posted August 17, 2003 Author Share Posted August 17, 2003 Thanks for the replies. I saw that the flagpole is the benchmark. The building in question is actually a pretty cool building (IMHO), it is like a minature version of the Woolworth building in New York. The flagpole is at the highest point of the building and I can see it as I type this post (I'd guess that is is about 500 feet from me). I agree that the Columbus/Columbian thing might be a typo - I'm not a native Memphian but I have done quite a bit of research into the history of downtown Memphis and have never seen any mention of a Columbus Tower. I guess that I'll photograph it and put a note in the log rather than logging a find. I'll probably leave the recovery note to someone more knowledgable in this field than I am. thanks, Jeremy A Quote Link to comment
+GeckoGeek Posted August 18, 2003 Share Posted August 18, 2003 quote:Originally posted by Raouljan: Besure to search the board for what "recovery" really means and how to file a recovery note Ok, so what does "recovery" mean when applied to structures such as a flagpole or light? Even if we were to gain access to the roof our equipment couldn't tell us if the object had been moved 6 feet. I've looked over a number of old threads but I don't remember that discussed in detail. Given that some of these stations where setup in the 1930, there is valid concern that the object located may not be in exactly the same position as originally monumented. Quote Link to comment
Z15 Posted August 18, 2003 Share Posted August 18, 2003 The designation is what it is. Its not going to be changed by NGS. This is one mark you cannot really recover unless you can confirm the position. Unless you are a surveyor and want to perform a lot of work to do this, forget about these intersection stations with vague decriptions. There is no way to know for certain you have the correct flagpole. Quote Link to comment
ArtMan Posted August 18, 2003 Share Posted August 18, 2003 From what I've read here, I would have a high degree of confidence that you've got the correct flagpole, and there is no reason not to log it here (at geocaching.com) as a find. If you have any doubts, though, there's no penalty for not reporting to NGS. I'm sure the status of such a prominent landmark is well known to local surveyors, who will not be fooled by the apparent typo in the building's name. Quote Link to comment
+Black Dog Trackers Posted August 18, 2003 Share Posted August 18, 2003 JeremyA - You need 2 pieces of data. 1. If you stand on the side of the building where the flagpole is nearest the street, how many feet away does your GPS say the mark is and is it within 50 feet or so? (This is an adjusted station, so the position should be much more accurate than your GPS.) If the current flagpole is the station, then your closest approach would be within 50 feet or so, demonstrating that you've got the right building. 2. How old is that building; older than (or equal to) 1929 or not? If it is that old, and it looks like it is, then you've got the same structure. I'm sure that if you entered the building, they'd be proud to tell you when it was built. If both 1 and 2 are true, then I recommend you change your report to Found on the geocaching site, but as elcamino and ArtMan point out, it might be best not to report to the NGS on this one. Quote Link to comment
+GeckoGeek Posted August 18, 2003 Share Posted August 18, 2003 quote:Originally posted by Black Dog Trackers:JeremyA - 1. If you stand on the side of the building where the flagpole is nearest the street, how many feet away does your GPS say the mark is and is it within 50 feet or so? (This is an adjusted station, so the position should be much more accurate than your GPS.) If the current flagpole is the station, then your closest approach would be within 50 feet or so, demonstrating that you've got the right building. Since I have the waypoint in my GPS I walk around two sides of the building. If the GPS keeps pointing to the building, then I know that I have the right building (I'm not very good at estimating distances.) quote:2. How old is that building; older than (or equal to) 1929 or not? If it is that old, and it looks like it is, then you've got the same structure. I'm sure that if you entered the building, they'd be proud to tell you when it was built. It can frequently be found on a name plate near the main entrance. You can claim this is "found" on GeoCaching.com. I'll have to check on NGS requirements. Quote Link to comment
+JeremyA Posted August 18, 2003 Author Share Posted August 18, 2003 Thanks again for the replies: quote:Originally posted by Black Dog 1. If you stand on the side of the building where the flagpole is nearest the street, how many feet away does your GPS say the mark is and is it within 50 feet or so? Will try that tomorrow when my GPSr arrives. quote:2. How old is that building; older than (or equal to) 1929 or not? If it is that old, and it looks like it is, then you've got the same structure. I'm sure that if you entered the building, they'd be proud to tell you when it was built. I know that the building was built in 1924. However, there is no one to proudly tell me the age of this building - like most of the more historic buildings in Memphis it is currently unoccupied. thanks again, Jeremy Quote Link to comment
2oldfarts (the rockhounders) Posted August 18, 2003 Share Posted August 18, 2003 quote:Originally posted by ArtMan:From what I've read here, I would have a high degree of confidence that you've got the correct flagpole, and there is no reason not to log it here (at geocaching.com) as a find. If you have any doubts, though, there's no penalty for not reporting to NGS. I'm sure the status of such a prominent landmark is well known to local surveyors, who will not be fooled by the apparent typo in the building's name. Artman has it right--- call on a local surveyor and ask him about that flagpole. 2oldfarts ******************************************************* Human beings can always be counted on to assert with vigor their God-given right to be stupid.--Dean Koontz Quote Link to comment
Z15 Posted August 18, 2003 Share Posted August 18, 2003 With all due respect to those that say contact a local surveyor. You don't want to be contacting a local surveyor over this. You are making a huge assumption that they are even aware this is in the NGS database or really care. Many are under the assumption that local surveyors use these, nothing could be farther from the truth I dare to say. Quote Link to comment
CallawayMT Posted August 18, 2003 Share Posted August 18, 2003 I have seen so many recent posts by people in regards to NGS markers being out, lost or destroyed along with the belief that local surveyors will reset these markers. Elcamino is right on the mark as far as his comment about not notifying a local surveyor. We do use the NGS control for varying projects and do rely upon them for large and small control projects, but very few if any private surveyors and even the depleted NGS ranks do not have the resources to replace these monuments. Most when lost, destroyed or disturbed are just that "lost for our use". If we can't find one benchmark we will move on to find a different one. As far as horizontal control goes; we will generally only use "A and B" order horizontal control for our GPS projects. Most 1st and 2nd order stations have been created using conventional methods and were built on NAD 27, which have been converted to NAD 83. This value is going to be too far from the 1-2cm accuracy we are looking for in most projects. And so old flagpoles, buildings, radio masts and even old triangulation stations are generally not used with todays equipment and standards. That being said for the benefit of some who do not understand how these monuments are being used; I want to say that there is nothing better than finding the old triangulation stations that were set in years past with a great deal of sweat and pain. We do appreciate all of the work that was accomplished during vast hardships by the old time surveyors. Regards Quote Link to comment
Z15 Posted August 19, 2003 Share Posted August 19, 2003 It should be also noted that once the mark is disturbed in the case of a bench mark (elevation) it is too late to reset. Reset needs to take place before the mark is disturbed or destroyed. Horizontal marks are hard to rest too, just bring up the underground mark will automatically downgrade the control class to 3rd order. Also reset BM's done to NGS spec's are also downgraded to 3rd order unverified. At the DOT, if we thought a mark might be disturbed or destroyed by some activity, we would go and set several temp BM's In the event it was, we could set a new mark from the temp BM's. This is only good for elevation control, horizontal control cannot be reset as easily, if it even can anymore. I once helped the NGS advisor move (see below) a triangulation station that was going to be lose by construction of US-2. It involved 2 days of work to build the marks, do all the observations and check all the field work. The NGS gu had to travel 500 miles and spend 2 days in the motel, as did I, not going to happen anymore. Just too costly and not needed when you can set another point, occupy it with GPS, process it with OPUS and it will be better than the old mark in most instances. The NGS Data SheetSee file dsdata.txt for more information about the datasheet.DATABASE = Sybase ,PROGRAM = datasheet, VERSION = 6.81 1 National Geodetic Survey, Retrieval Date = AUGUST 19, 2003 QL0651 *********************************************************************** QL0651 DESIGNATION - WILSON 2 QL0651 PID - QL0651 QL0651 STATE/COUNTY- MI/MENOMINEE QL0651 USGS QUAD - WILSON (1989) QL0651 QL0651 *CURRENT SURVEY CONTROL QL0651 ___________________________________________________________________ QL0651* NAD 83(1994)- 45 42 19.47888(N) 087 25 10.36202(W) ADJUSTED QL0651* NAVD 88 - 248. (meters) 814. (feet) SCALED QL0651 ___________________________________________________________________ QL0651 LAPLACE CORR- -4.03 (seconds) DEFLEC99 QL0651 GEOID HEIGHT- -35.54 (meters) GEOID99 QL0651 QL0651 HORZ ORDER - THIRD QL0651 QL0651.The horizontal coordinates were established by classical geodetic methods QL0651.and adjusted by the National Geodetic Survey in February 1997. QL0651.No horizontal observational check was made to the station. QL0651 QL0651.The orthometric height was scaled from a topographic map. QL0651 QL0651.The Laplace correction was computed from DEFLEC99 derived deflections. QL0651 QL0651.The geoid height was determined by GEOID99. QL0651 QL0651; North East Units Scale Converg. QL0651;SPC MI N - 102,570.842 7,967,330.285 MT 0.99995370 -0 18 11.7 QL0651;UTM 16 - 5,061,403.042 467,341.695 MT 0.99961311 -0 18 01.1 QL0651 QL0651: Primary Azimuth Mark Grid Az QL0651:SPC MI N - WILSON AZ MK 092 07 08.6 QL0651:UTM 16 - WILSON AZ MK 092 06 58.0 QL0651 QL0651|---------------------------------------------------------------------| QL0651| PID Reference Object Distance Geod. Az | QL0651| dddmmss.s | QL0651| QL0656 WILSON AZ MK 0914856.9 | QL0651| QL0653 WILSON AZ MK 2 APPROX. 3.0 KM 0920345.7 | QL0651| QL0487 WILSON 8.162 METERS 22702 | QL0651| QL0652 WILSON 2 AZ MK 3 487.902 METERS 2603223.9 | QL0651|---------------------------------------------------------------------| QL0651 QL0651 SUPERSEDED SURVEY CONTROL QL0651 QL0651 NAD 83(1986)- 45 42 19.47752(N) 087 25 10.36056(W) AD( ) 3 QL0651 QL0651.Superseded values are not recommended for survey control. QL0651.NGS no longer adjusts projects to the NAD 27 or NGVD 29 datums. QL0651.See file dsdata.txt to determine how the superseded data were derived. QL0651 QL0651_U.S. NATIONAL GRID SPATIAL ADDRESS: 16TDR6734261403(NAD 83) QL0651_MARKER: DS = TRIANGULATION STATION DISK QL0651_SETTING: 7 = SET IN TOP OF CONCRETE MONUMENT QL0651_STAMPING: WILSON 2 1988 QL0651_MARK LOGO: NGS QL0651_MAGNETIC: N = NO MAGNETIC MATERIAL QL0651_STABILITY: C = MAY HOLD, BUT OF TYPE COMMONLY SUBJECT TO QL0651+STABILITY: SURFACE MOTION QL0651_SATELLITE: THE SITE LOCATION WAS REPORTED AS NOT SUITABLE FOR QL0651+SATELLITE: SATELLITE OBSERVATIONS - 1988 QL0651 QL0651 HISTORY - Date Condition Report By QL0651 HISTORY - 1988 MONUMENTED NGS QL0651 HISTORY - 20010331 GOOD NGS QL0651 HISTORY - 20021030 GOOD USPSQD QL0651 QL0651 STATION DESCRIPTION QL0651 QL0651'DESCRIBED BY NATIONAL GEODETIC SURVEY 1988 QL0651'THE STATION IS LOCATED IN QUAD. 450871, ABOUT 9.7 KM (6.0 MI) WEST OF QL0651'BARK RIVER, 7.2 KM (4.5 MI) EAST OF POWERS, AND 0.8 KM (0.5 MI) EAST QL0651'OF THE VILLAGE OF WILSON. OWNERSHIP--HIGHWAY RIGHT-OF-WAY. QL0651'TO REACH FROM THE CAUTION LIGHT IN BARK RIVER, GO WEST ON U.S. HIGHWAY QL0651'2 FOR 3.62 KM (2.25 MI) TO THE HARRIS POST OFFICE, ZIP 49845, ON THE QL0651'LEFT. CONTINUE WEST ON HIGHWAY 2 FOR 5.53 KM (3.44 MI) TO THE QL0651'STATION ON THE RIGHT ATOP THE HIGH CUTBANK AS DESCRIBED. QL0651'THE STATION IS SET FLUSH WITH THE GROUND. IT IS LOCATED 1.829 M QL0651'(6.001 FT) NORTH FROM THE EDGE OF CUTBANK, 0.914 M (2.999 FT) QL0651'WEST-NORTHWEST FROM A 5 INCH PINE TREE, 0.762 M (2.500 FT) EAST FROM A QL0651'6 INCH PINE TREE, 0.610 M (2.001 FT) SOUTH FROM A CARSONITE WITNESS QL0651'POST AND 0.305 M (1.001 FT) NORTH FROM A CARSONITE WITNESS POST. THE QL0651'UNDERGROUND DISK IS SET 1.0 M (3.3 FT) BELOW THE SURFACE. QL0651'A TRAVERSE CONNCECTION WAS MADE TO STATION WILSON 1954 USING QL0651'STANDARDIZED STEEL TAPES AND TO WILSON 2 1988 AZIMUTH USING QL0651'ELECTRONIC DISTANCE MEASURING EQUIPMENT. QL0651'HEIGHT OF LIGHT SHOWN WAS 1.5 METERS ABOVE THE MARK. QL0651'DESCRIBED BY RONALD L. RAMSEY, GEODETIC ADVISOR - MICHIGAN. QL0651 QL0651 STATION RECOVERY (2001) QL0651 QL0651'RECOVERY NOTE BY NATIONAL GEODETIC SURVEY 2001 (DB) QL0651'THIS REPORT WAS SUBMITTED BY THE US POWER SQUADRONS. QL0651 QL0651 STATION RECOVERY (2002) QL0651 QL0651'RECOVERY NOTE BY US POWER SQUADRON 2002 (BAA) QL0651'RECOVERED IN GOOD CONDITION. *** retrieval complete. Elapsed Time = 00:00:03 Quote Link to comment
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