evenfall

Paul, Mike and Jerry, Pulling the Datasheet for FA2610 tells a lot more of the tale... It looks like in '48, CGS set station Mocksville, FA2610 and not only tied in FA2608 as a reference mark, it was also tied in on a traverse. It looks like FA 2608 was a station set in 1899 by NCGS. It was in a cluster of other stations set by NCGS at the same time. In 1948 CGS set FA2610 and used 2608 as both an RM and tied it in as a Traverse at the time. There was other stations found in place including a Transit Traverse station set by the USGS also. FA2608 seems to be Second order horizontal control now, but it is not likely it achieved Second order until it was made into a NCGS HARN station. A traverse would not usually qualify for second order control. More of what was done becomes clearer, sort-of, by reading the other datasheet. Hope it makes more sense now, or this way... The HARN stations in the Carolinas seem a bit interesting as it is... In an odd way. It seems the control is proprietary and unable to fit other control... Weird. Thanks for the weirdness Paul! :-D Rob

Of note: On the second drawing Kenewah has kindly submitted, I would like to call attention to the section view. Though this is a typical installation of this monument, there are variations so don't be surprised if this is not exactly what you encounter. First I would like to touch on the safety aspects that go with this particular monument type. This is the type specified for placement in the street, so should you be interested in one of these, you too will also be in the street. I just want to remind those who may want to look inside that you will likely not be able to get the cover off with your bare hands, It will require a tool, and while you are trying you are in traffic and exposed to all the hazards which go with the territory. Quite Frankly you can Die trying to fool with it from contact with traffic and I know, make that used to know several people who have and are no longer here. Should you choose to have a look, Don't do it alone, two friends looking out for traffic are better than one, eyes and ears are important here, and the requisite safety gear you would see any road construction crew member wearing would not be a bad idea. Often we surveyors do not wear a hard hat unless we are working where one is required, but always a vest. Always. Second, down through the years there have been variations on the theme used for this type of monument. Some Are just as you see, others have just a rod and no concrete around it, some have other things. Vaguely put I know but just trust me. Hubs, rusted nails and rotted wood, etc... On many, if they are old, the monument cover itself has likely been jackhammered out of the pavement after road resurfacing operations to reset it to the current level of the street as that may be the specified method in that jurisdiction, or a ring may have just been placed to lift the cover higher in others. Sometimes the crew raising utilities do not perfectly center the cover so you may find odd settings that way as well. I won't go into the method of Madness and other reasonings but this is common stuff to see when taken as a whole, so you may find that the survey marker under the monument is a good bit deeper or in other offset manners than the section view will show. These also often fill with dirt and the dirt would have to be moved or removed to find the rod marker in there. Leaving the dirt in the road is bad form so if you must remove the dirt, try to leave no trace when you finish. In my spare time I usually avoid bothering with these due to the lack of safety involved in trying to recover them properly. I can't see traffic while standing on my head. I have all the right stuff at work and can set up the proper traffic control. Interestingly though I have recovered a few in my life that were not there due to utility construction removal, where they put the monument cover back in the street after digging the monument up in construction to facilitate themselves. The hope on their part would be that the cover will put the inspector off the trail that there was a marker removed and they will sign off on it. All looks well but the next crew who needs to use the point will find nothing and the construction company is long gone. All the richer for not having paid to have the point re-surveyed. It happens. Other times finding the station covered with asphalt or concrete... And so the big thing to remember is that the monument cover is not the monument, the place under the lid is not always what you might think it is supposed to be and the location is often a dangerous place to be. Good luck and safe hunting, Rob

Jim, For help with the NGS Datasheet in itself, try this page: http://www.ngs.noaa.gov/cgi-bin/dsformat.prl Once there, you will see a list of 21 optional datasheets that describe various different types of stations. Once you highlight a selection on the list and load the sample datasheet, you will see a datasheet that is similar to what you have been seeing, which many of the terms on the sample will be hyperlinks to definitions for those terms. You will see the hyperlinks from the different color used than the text, and though that is stating the obvious it is a clue to other things. There is in addition to words, a bracket ( [ ) along the left edge of the text on a part mid way down on some but not all pages which will lead to a definition about what this section on some Datasheets represent. Once you understand how to use the datasheet, by deciphering the code it has, you will find them pretty simple to read and extremely straightforward. Click all the definitions and feel free to familiarize yourself. This is probably the most succinct way to present all the various information there is for a station, no matter how much of it you intend to use. It is a great page to revisit from time to time, as it will unlock the secrets of the datasheet. Enjoy, Rob

Buck, Perhaps you were walking down more than one road in your mind than I am following... Why is the geocaching database incomplete? Ok, I'll Bite, What would complete it for you? It is a __copy__(unmaintained) of the NGS Database but is not the actual one which is complete. The NGS feels it is quite complete as based on their needs... I could go on but I want to see if you clarify more, and look at a few of the other recent posts from the past few days, there you will find references to the FAQ and some other posts which familiarization with to get up to speed. The reason an old stack may have never been revisited can be many, and a good bit of finding out the details is part of the Mystique of benchmarks... This mystique is meant for you. It is but one of your burning questions to answer. Trust me, there will be others. Rob

CaliCoe, You may find that in many cities and municipalities, there is a monument of some kind, in the center of most intersections. They were placed there by the municipality and there is likely a lot of information ascribed to them based on different projects down through the years. Planning, Engineering, Water, Sewer, Streets etc... They may be either or both a known point of location and elevation. Most often, they were placed to represent centerline of road, as based on the original design. Sometimes things change but the control remains where it is as there is a good bit of info described by it, from the past, and it still serves as a place which new things can be described, whether as offset or otherwise. Now that you know, you will likely see some derivative of these everywhere. Some may have been used by Geodetic Surveyors, as a borrowed monument (using a monument already found to be installed and permanent enough). Some you may find here at geocaching, but that would be more an exception that the rule. Depending on the city, some engineering departments do list their survey control online, but again, that won't make it a game piece for here on geocaching, remember to check here first for those that are loggable here. Enjoy, Rob

edscott, There is also an old post I wrote about this topic while back that may also be something that you may find informational about survey markers not in the Geocaching database, I hope between all this information that you come out with a fair understanding. You can go directly to this post by clicking HERE. Rob

One further point of interest to lurkers. If you didn't get a GPS for Christmas, this does not need to stop you from being able to participate here. Though it is true that the GPS is instrumental in geocaching, it is but just one more tool in our benchmark hunting arsenal, and not one we absolutely need for all finds. Most of the benchmarks I hunt are found strictly with the datasheet information. Yes I have had to use the GPS on occasions, but as a tool, not the sole reason to hunt. I like hunting without the GPS, as I like the challenges and being in the moment, and I like seeing how well the previous descriptions were written and if I can improve them with my filing, but if I have exhausted the available resources, the GPS comes out. I can use the GPS on scaled locations to add accuracy to the location but again, it is not preventing anyone from attempting the hunt. There is a lot of great reading and info here in the forum by many contributors and it is rewarding to hear that lurkers read and get something from it. So feel free to contribute, ask questions, hunt if you want to. Any question unasked is just a question unanswered. GPS or not, it is nothing that will stop you. Find the ones you can for now and return for the harder ones later. There is no sense in waiting to have the fun. There is a list of useful things to use to hunt benchmark, but the only one you cannot do without is the data telling you where to hunt. If you are here, you already have the means to get that. I hope I have removed the block to further lurking. You need not sit on the sidelines while others do this. you can too. Now get out and have a great time, we look forward to your shared adventures. You are all welcome to join us anytime, whether you have found none or a bunch. Waves, Many Congrats! Rob

Greg, I think it will work fine, it is just text file data, and though you can choose 200 one way, if you go the county route you also have the option to select only the marks you want from that county. These programs aren't something I use, but on this end I use the Datasheet site in all ways and my computers treat all of it as text. 2oldfarts had some great info on mark hunting using the geocaching site in a previous post as well. It seems that the best of all worlds is to use both. Play with it, what would be the harm? We all learn the cool new stuff this way. Rob

I believe you can ask for up to 200 PID's at a time from the datasheet page also. Rob

Good on you Dave! That is awesome. The oldest stations out west here are 1854 at earliest. Both those are quite a piece of work. That makes this a sort of red letter day! I am just curious, Did the geodetic azimuths work out as compass headings based on the direction of south, as they did on the last one you and I discussed? I see the First order station on Mt. Esther is basing the RM locations on Geodetic Azimuths. Again, Nice find! Rob

Neweyess, Here is the latest from the NGS Datasheet: FA4616 STATION RECOVERY (2000) FA4616 FA4616'RECOVERY NOTE BY NORTH CAROLINA GEODETIC SURVEY 2000 (JGG) FA4616'RECOVERED AS DESCRIBED WITH THE FOLLOWING ADDITIONS. MARK IS ABOUT FA4616'1-FOOT LOWER THAN MATTHEWS-WEDDINGTON ROAD AND IS RECESSED 6-INCHES FA4616'BELOW GROUND. LOCATED 21.5 FT (6.6 M) WEST OF THE CENTERLINE OF FA4616'MATTHEWS-WEDDINGTON ROAD, 214.4 FT (65.3 M) SOUTH OF THE COUNTY LINE FA4616'SIGN ON THE WEST SIDE OF THE ROAD, AND 136.1 FT (41.5 M) NORTH OF A FA4616'TELEPHONE PEDESTAL. So if you take a small garden shovel, that station may well be at the bottom of that hole you found. This is a station which is put in place by driving a steel rod to refusal. What this means is that there is a stainless steel rod which has lengths that can be attached together. They just keep adding to it and pounding it into the ground until it stops. Refusal means it won't go in the ground any more. Then they attach the disc to the top. There is more to it than that but you get the general idea... I am thinking if you dig a bit, all will be revealed... The garden trowel is the key. This is a HARN station monumented in 1988. 35 03 57.11190(N) 080 43 42.28543(W) D/M/S First order control. Your GPS with that NAD 83 waypoint should point right at it. Good Luck, Rob

Doc, I am in understanding with what you say, in fact you have said many things I have said here many times but not in complete agreement. We see the world a little differently but mostly the same, I take no offense at all. NAD 83 compensates for a lot of Tectonic plate movement we see here out west, and is specialized as a Datum for the North American Continent and so it is much more accurate than WGS 84 in this country. I am aware we tossed NGVD 29 out in 1991 and now go with NAVD 88. Not just the former reference of 26 tidal stations as opposed to a single one in Quebec, but they were right to confirm that mean sea level as a stable actuality does not exist. It was basically the Surveyors Loch Nest Monster, an elusive creature. Since we have an unstable apple and an unstable orange, yet they need to be compared by virtue of both being fruit that grew on trees as a commonality, what can you do? This is what Vertcon tries to attempt. I mean if an orthometric height comparison is needed between datum you are bringing Geoid height and ellipsoidal height to the table, Orthometric height differences can then be obtained from ellipsoid height differences by subtracting the geoid height differences. As an orthometric height is a derivative of a geoid height, (which model?) and an ellipsoidal height, (again Which model?)(NAVD 88) We have to define our terms and remember that Clarke 1866 was not used Vertically,(NGVD 29) and sea level is ah.... Tidally dependent on 26 averages that were ahhh not then known to be geoidally (gravitationally) dependant.(NGVD 29) When even differential leveling is path dependent, taken as a whole, it is a tough apple and orange to compare, yet all considered orthometric heights all the same. I am also aware that when NAD 83 was adjusted from NAD 27 all stations were not changed with a Nadcon or Vertcon adjustment. You are correct in stating 67% confidence but the ballpark is taken as .15 meter in the continental US and that is 6 inches roughly. With it we should be able to use the NADCON program to Find the survey marker and that is good. If we are a Surveyor, we then know what we need to do. If we actually have to use NADCON or VERTCON, then the survey is considered low accuracy, the onus is on us to state this and the buyer is beware the accuracy. Accuracy is plainly stated by NGS. I am not saying I don't find errors either because I do. But it is not with A, B. and first order work as much as with third order. There was a least squares adjustment based on new leveling and triangulation of the networks during the 80's. I take the NGS term ADJUSTED to mean a least squares adjustment rounded to the fifth decimal. Not bad really, and close enough for most infrastructure. Yes there are inaccuracies, but I am glad I am not doing this with a Wild T-3 and paper with pencil, aren't you? Besides, the entire NGS database is not the NSRS. I have found GPS comparisons to be very good with the NSRS data, and Optically triangulated third order stuff is not taken as NSRS quality. I don't take the Geoid in either 99 or 03 to be a static force so I realize despite the spheroid models being used, the earth constantly moves, the atmosphere and it's distortions never end, the constellation of satellites is up and down, on and off and there is no less than several government agencies in control of each little part of the puzzle. Either way, when you get to the highest accuracy, there still is no one sure place. If you could attain it you would never arrive at the same number twice. Either way, that one sure place is a difference of approximately 1 meter due to the datum shift between NAD 83 and WGS 84. Besides, It is all in constant motion. This big earthquake a week ago has not done us any favors when it comes to trusting numbers. I would say that many bets are off on Geoid 03 now. It seems hard to trust a Gravity Model after a 98 foot tectonic shift. Beyond that, Both NGA and NGS have done so much accurizing of both their Datum as it is that they really only continue to call them by those names as a political courtesy. Neither one of these are close to the datum they were when so named. We are aware that political needs come before the scientific needs. Always has. Prepare for another update soon. As for HARN problems from State to State, and the fit problems, well I see that as a bit of a political situation as well. I have heard that not all states are playing the HARN game the same way and until they do, I don't see how we can really ever prove a thing. Again a Political problem is likely the culprit more so than the science. More so, no one will ever officially comment as such and we both know that. If it is the science, we would have to see after we cure the political problem. Science has been found to not best describe reality before so I would not be surprised. In these parts we still have counties that insist all vertical control be done to NGVD 29 Datum. But cross a city limits the vertical control becomes NAVD 88 Have that County road hit a State Highway and you immediately have a Datum Shift. Yup, It's a pain. All Political. You can take my old datum if you can pry my cold dead fingers from it. Imagine the fun I have laying out a gravity pipe job complete with datum shifts. Bleh. Each municipality will extract it's due. Most interestingly this horror tale often comes true brought by a inspector who has never heard the word Geodesy. The Hellbentness that you say about NGS is true in the respect that they are finding better ways to accurize their Datum as the science and technology becomes available, besides, I am not sure we know all there is to know about geodesy yet. From what I read, there is a lot still being revealed. Don't get me wrong, I am not trying to big deal it but look how far we have come in the last 40 years, 20 years, and 10 years. Maybe the 6000 became 600 but much of the heavy lifting that once was necessary is done, and done by old ways. We have easier ways now. I was a member on a crew of 3-4 back in the Day and most of the time I am now a force of one. I think NGS probably let go of 2000 of the bunch of 6000 when computers took over the calculus. That was a lot of pencil and paper... Since WGS 84 is used worldwide by other countries and governments, those countries (Europe, Asia) who use it become a local accurizer of that datum, and are equally hell bent, So much so that they are developing their own GPS systems and Datum, so you see it really isn't different, other that the truth of the political matter. WGS 84 is really about DOD and that means Bombs and missiles, and here in this country there is not a lot on the ground to accurize it. NAD 83 is about the north american continent. When it comes to what is going on in the dirt on this continent, I feel the NAD 83 is far more accurate. Either way, I have to tie in to the right numbers. The difference truly is that Plate movement is different in North America, and WGS 84 was not developed to account for it. The question of accuracy is highly unanswerable the closer we get to it. It is like the last mile of a fiber optic network or absolute zero. You are right, It is nothing which can be seen in the hand held unit of consumer grade accuracy, but it is not correct to have people think that WGS 84 is substitutable for NAD 83 as that is not correct and wrong minded. There is no point in developing bad habits or wrong thinking at any level. It doesn't serve anyone well. And no, I don't use Nadcon or Vertcon for hard survey numbers. Those have to come from field observations as you know. But they have their uses. In the end, I am not trying to argue the Math with you Doc, nor am I really trying to contradict you, as all your points are good in many ways, but this is the system we have and despite flaws distortions or Fubars, it is what we have and we should use it. It came from marginal instruments and mathematics which had barely been developed to what we have today. We did give up Clarke 1866 for GRS 80 and we may yet give up GRS 80. I know it is a pain and a work in progress, but still I'd like to think of things becoming more correct, not less. We may be able to measure to the gnat someday, if we can find the gnat and get it to hold still. Rob

Ted and Bill, You make good points. The PID system was developed for use with Computer Data Filing, The "A" series marks are Miscellaneous marks which often include but are not limited to GPS Control, HARN, CORS, Primary and Secondary Airport Control, as well as other geodetic projects and measurements. The rest of the system is not abandoned, however in some cases and places many of the numbers are used up. This can also serve as an overflow for that, and in some cases does. Rob

To All, We all find mistakes and errors in the database, regardless of who made them, and sometimes we may find that we made them too. No Biggie, Just put a best face on what you find and report it. If you find a not found, you can improve upon the last known condition in the database, by reporting it found, and submitting some photos. If you like, the NGS will be happy to have your update. Again, it is your choice, but if you do not want to go with an NGS filing, don't let this not found stop you as you may just bag it for a find on Geocaching. Go hunt it anyway. Besides I think Black Dog Trackers submitted the idea that there are extra points garnered for USPSQDN not founds eh? :-) I know when they file a not found I take it as a go look anyway... Like I said in the quote that started this tread... Recovery by people who would rather be spending their weekend on a boat. ps, Thanks for sharing the pain Dave :-) Rob

TruFinds, If they are not listed online for logging, then they do not belong to the National Geodetic Survey, and as such were not set for Geodetic purposes. However they may have been set by a different agency such as the US Geological Survey (USGS) and the data for them may be Geologic or Topo and belong to them. It sounds like a very cool find. Certainly a very unique place to find survey markers. I know a lot of folks would enjoy seeing and hearing more. Enjoy, Rob

Bicknell, Here are a few thoughts on JV4487 DESIGNATION - LOUDOUN FAIRFAX BDY HERNDON. Ok, this was a Nail driven in the top of a 1x2 stake in 1954. This stake was likely rotted off by 1959. Stakes are untreated wood so, it was worm food. I have revisited a lot of wooden survey in my day and well, the weather in a few years is not at all kind to it. Even if this were still a field, there is no chance of it existing 10 years later at best. The FAIRFAX-LOUDOUN BOUNDARY COMMISSION was to have created a station here but if they did, they never reported it to NGS as a radial search of the NGS Database for this location shows 4 stations within a half mile of here and it is not listed. So this boundary commision is not required for the recovery of this station. it was not updated further than this to the NGS, ever. As to the asphalted parking lot, if this station was a wooden stake that would now be 50 years old, and it is gone. To build such a parking lot, all the topsoil would be stripped from this location and crushed rock hauled in to create a stable compacted sub grade for paving prior to laying the asphalt. This station will likely qualify as a destroyed for geocaching, and a Not Found for NGS Recovery. Again, you are not required to file what you find , or don't find, with the NGS, Unless you choose to. One other quick tip, which you may already know. The best satellite constellations are during bankers hours, so for a lock with highest accuracy, with weather not a factor, between 8:30 AM and 4:30 PM will bring you the best look at the GPS Birds. If too many are directly above you, or too low on the horizon things can become problematic. Above offers a weak spread, and the Horizon can offer an attenuated signal. I am not saying that other times of day are bad, just that this time of day is optimum. Enjoy, Rob

Doc, Almost all recovery of NGS station recovery is done by Volunteers these days. The amount of survey in the field is massive but the NGS is not funded by the Department of Commerce as such so as to be able to pay a force who recovers these and has not for years. In fact NGS has very few Paid Survey Crews these days either. In much of the work, Most States employ Surveyors with equipment of high enough quality to maintain the geodetic needs of the states and a lot of this is brought to NGS Standards for obvious reasons and reported by liaison through State/NGS Geodetic advisors. Today most states and may counties and cities are involved. Todays equipment enables this work to be done to extremely high accuracy without the use of large crews. It has become a GPS World. Whomever chooses to report what they find to NGS becomes a part of the all volunteer force. Even I as a surveyor on the clock can submit my findings to the mark recovery page on the NGS website but even on the clock, neither I nor any employer will be remunerated for my efforts at any level though I would technically earn my wage at work during business hours. But the recovery would be something my employer would be paying me to do, which is something they would never recover the costs of. No Matter, I do it on my own time for free. I like the challenges, some of these are tougher than a chess game in that I can lose track of time doing it, and I like it. I imagine if it were easy, I probably wouldn't enjoy it as much. No station ever monumented of any kind is updated in the NGS prior to being looked at by NGS Personnel. So to a degree, it is looked over, but they are relying on you to do your best. They are hoping that we will do so with integrity. They do not allow the submission of destroyed marks through the mark recovery website. The only kind of station that NGS will allow to be destroyed without empirical evidence of destruction is a Landmark type station. This can only be done via email and the criteria is strict. Stations which were Discs, or otherwise monumented as points that could be occupied with an instrument set up, cannot be destroyed in the database unless you can furnish the destroyed object. Basically put, NGS likes that you are interested and wants to help you become your own "Mark Duster" They are very happy about the contributions from Geocaching. There is in fact a very exact conversion to calculate the datum shift between the NAD 27 and NAD 83 Horizontal Datum. It is a program called NADCOM and it is available on the NGS website both as a Javascript online and as a download to run on PC. The NGVD 29 and NAVD 88 Vertical Datum can also be converted as well , both similarly, with a program called Vertcon. NGS has a large number of programs that will convert a number of data type for the interest of geodesy. Two points of interest, I can hunt them in either Datum and they are accurate to better than less than 6 inches, most usually to way way better than 6 inches accuracy. In either datum with or without conversion. All Active Horizontal control in the database has been converted to NAD 83 so it is current data and this is stated as such as such in the datasheet, the superseded control is there as well. You can play with these programs by going to http://www.ngs.noaa.gov/ then look at the Geodetic toolkit and the software downloads. As to disservice to professionals? well I see this mistake happen but it is a human system, so it happens. I don't choose to see it as a disservice as Surveyors sometimes don't find them too, then we find them later, or next time. If you like, you can report only ones you find, and not the ones you don't. At least you are helping freshen the info on ones that are known to you, and not making a mistake on any that you just are not sure about. By just reporting the find only, everyone helps out a lot. I am a surveyor, I do use these and am happy to see the updates. It is cool if you try to use the old description to see if it still works. If Not, A GPS Waypoint made from the Coordinates will take you straight to horizontal control, if the description is no longer working, you may choose to provide to write a new one based on the way the object can be found today, if you are recovering to NGS. If you are just playing the Game then a simple found it will suffice. Many of the recovery narratives on Datasheets are a great guide to use in how to best write a description if you want. No one is under any obligation to report what they find, or don't find to NGS, unless they choose to do so. The Main thing here is to have fun with the challenges, the hunt, the history, the sightseeing, and the fellowship in the forum. Rob

Bicknell, PID DATA ITEM: Station Permanent Identifier (PID) DISPLAYED: Always COMMENTS : The PID is also found on the left side of each datasheet record. The PID is always 2 upper case letters followed by 4 numbers. EXAMPLES :________________________________________________________________ AA3495 PID - AA3495 RF0849 PID - RF0849 TV0007 PID - TV0007 DESIGNATION DATA ITEM: Designation DISPLAYED: Always COMMENTS : Usually the DESIGNATION does not match exactly with the STAMPING. EXAMPLES :________________________________________________________________ AA3495 DESIGNATION - GAITHERSBURG CORS L1 PHASE CENTER RF0849 DESIGNATION - CARIPORT CA0570 DESIGNATION - MP 77-5015 AA8531 DESIGNATION - 66-26 And By Roger, Rogbarn, a fellow benchmark hunter, a grid sheet he developed, based on the Latitudes and longitudes of the US and how the NGS Prefixes would overlay each area, Have a look at it Here. There is a graphical look at the same thing, hosted by sbolish, Here. Enjoy, Rob

Paul, You know that guy wasn't all that old... Think that benchmark is a darwin award? :-D Rob

Hi Harry, Don't worry about the Bruhaha, you didn't start it and it is of little matter. it will take longer to solve than one day :-) There is a cultural divide in the benchmark forum of those who want few rules because they seem to be uncomfortable with the rules as they are, and others who feel the rules are something that bring integrity to the game. Interestingly, there are few rules and they were decided by Benchmark hunters in the first place. There are usually people who come down on either side of an issue. Either way, there is still room in here to do it all, Read just the topics you like! Like I have said and will reiterate, you are under no obligation to log anything with the NGS. Nobody is. Some people just don't want to. That is ok! You may if you like. If you choose to or not, No matter. What I hope you will do is have a good time benchmark hunting, and if you have a question, I hope we can help get you an answer. Some never get the answer they want but we as a group in here hope we help most folks. Rest assured. The NGS police will not be coming to pick you up. :-) KU2166 can be tested by loading the coordinates into your GPS and running a Go To, to see if it points to that location. To test further you can circle the object to see if the GPS continues to. Being first observed in 1986, I would say you may have your light, but that is how I would check, The USCG Light list is free and online so you could verify this in there as well. See what you can find. It is one of the challenges of the Hunt. KU3961 is a 1932 station. It can be tested the same way as KU2166, but it is very old for a light, and was likely made from wooden pilings. I doubt it to be there, and if something is, I am in doubt that it will be this object, as many of these old lights can only do water for so long. The unlikelyhood of this being the original if at all is why we need to be careful if we care about the quality of the recovery. KU3952 is a no brainer, you didn't observe a flagpole at all, but here is the trick, if you did, from that far away can you be sure that it is the original in the original location from 1932? Not unless you go to the island. as for KU3956, my reservations about KU3961 would apply. KU2165 I would treat it same as KU2166. KU3544 is one which may be a new one erected in the place of or same location as the old one. Here in Seattle we have a ton of these Lights in the database and I generally don't fool with them, because even after asking, no one is sure they are right. I would have to survey to check them for sure and I bet it would be a waste of time after the fact. 50 years with no recovery then recovery by the power squadron means there is something there but likely not the original item. Generally something that old in the water will likely have rusted and rotted by now so go figure. Is it the original item? As to the Absurdity, well yes some are, but they did exist once and were surveyed then. They, or rather the position they were once in helped develop the system that is still in use today. It is inevitable that some things come and go. And finally yes it is a game. A game many feel functions best when we do scrutinize ourselves and be sure to really find the real object like the FAQ says. As to the NGS recovery, it is something you can elect to do as well, says so in the FAQ. But if you want, just keep in mind that the requirements are different and sometimes confusing when we compare them to the game. Some players want to do this though and have questions, and that is why we try to answer them all as best we can here in the forum, game wise or otherwise. It is nothing anyone has made a big deal of, it is just another aspect of how the game can be played here on geocaching.com. Happy New Year Harry, Rob

John and Shirley, I understand your observations, but I also understand other peoples observations. I will come down as Artman did on accuracy. In caching there are a great deal of flame wars that go on about cache approval and statistics. Here there are no cache approval like situations. there is no log book to find and sign, no owner to disapprove our find. We photograph and document as we do to police ourselves and since most people bother to do so, I assume that they feel that it absolves them of having to explain if they were really there. We have what we have, and yet though there are 736425 benchmarks in the database, and only 56240 uniquely found. We are often asked why we can't add others. There is no treasure here other than the find and the hunt itself. Many times there is nothing more than good hunt and no find. The challenges here in benchmark hunting are different yet there are many ways we can test to see if we are correct, and hey, some of us like being correct if we can. The gist of what I read here in this forum is that many feel that way as well and seem to encourage others on a not found, in fact when I see anyone post asking a question about how to find a problem benchmark, I see no less than 10 benchmark hunters crawl out of the woodwork trying to help with information from every kind of map on earth, satellite photos, older datasheets, hours of study. Sometimes mistakes are made but for be biggest part of all benchmark finds that is an honest find. We have learned about many different kinds of survey, not because I or another surveyor in the forum took it upon ourselves to subject anyone to anything, but rather because somebody, generally a non surveyor, asked. Please note that it is not often a surveyor who starts a topic in the forum, but we don't mind cheerfully helping. I have never seen any one in this forum who works in the survey field pat themselves on the back for being here either. They all try to give the best, most complete answer they can, each in their own way. Others who are not surveyors contribute just as much and my hat is always off to all of them, including you. There are so many people willing to help without asking for anything in return here, and I think it is just plain cool. My Responses may not seem simple and to the point by your measure but that is your way of measuring me. I have accepted that rebuke from others in the past as well, but generally I overlook peoples innuendoes and sharp elbows, yet I do make note of them. In otherwords, your subtle comments have been noted from time to time and they really don't change things do they? :-) Please keep in mind that I generally praise you for the cool things you do. Looking back I realize I write verbosely but I am on topic, and what I share is as complete a picture as I can. Most surveyors know that there are few simple answers to anything and most are never short ones either. The subject of surveying is a different subject than any other. It is one of the worlds oldest professions and has seen more evolution than most. When the uninitiated asks to be initiated, they want to know. Sometime knowing more is better than knowing less. I never know who they are or what they know. I keep in my mind that other people read this forum even though they do not post here, and so it goes without saying that they may benefit too. As an example a thread may begin with a question, and this is obvious. By the time the 5th post is there, other questions have been raised while taking a stab at it, and the topic is turning both left and right, I figure what the hey, I'll try to cover as much of all of it as I can. Why? Because this forum has proven over and over again that there is just not a simple answer, and even the surveyors will agree where several of us have weighed in on a topic that we didn't tell all of the story so another helps out with more story. We get regional points of view, we get the benefit of a lot of experience. Perhaps people are posting less because their questions have already answered in many ways and so now they know, they don't need to ask. While we are in Perhaps mode I'll explore another perhaps or two. I have read where some people burn out from geocaching in other forums John, Shirley. Could it be that a benchmark hunter gets burnout too? I haven't asked and I am not asking now. I just figure most people do what they want. Perhaps we are in December now and in fall season for three months where kids are in school and vacations are over, the weather isn't as nice and many people have throttled back on the hobby for the year... Again, I haven't asked but it seems reasonable to me. People lead busy lives, but I am sure that most people out there are actually curtailing their benchmark hunting activities as a silent protest to me and my verbosity! Yeah, that must be it... Thanks for pointing that out to me :-) I don't see the decrease as a problem, people come and go in any forum, any hobby... In fact, what about the people posting here all the time who are new? I see new all the time, and enjoy it all. I have noticed for quite some time that the NGS sticks in Both of your craw... That is fine. I Don't press NGS recovery, But I do delineate both ways because many of the questions asked here in this forum are based on the confusion caused by the different ways of reporting a find. Regardless of how you personally feel, I write to help people understand the difference. Something that often happens is a new hunter will ask a question. This is common. By the time 4 people answer that person they have 4 different answers, and often the answer is based on the question, but only in part, the rest is skewed towards the kind of recovery the answerer likes to do. You may not like it that the NGS gets brought up, but many other people do and this forum is for them too. Sometimes people answer a Geocaching question with an NGS reporting answer. The differences are often confusing to the uninitiated. They are often just confusing period. Many people answer out of zeal for the hobby and the way they see it. I will never stand in their way, and I enjoy their zeal, but I will post my own thoughts and let them stand as mine with respect to everyone else's. I try to explain the differences because they are there. I want to help get them all an answer, no matter what it may be. I figure they read it all and take what they need. Leave the rest. I always attempt to explain the differences if I see them and though I do report to NGS myself, and enjoy my hobby that way, I never have advocated that anyone else should do as I do unless they want. I have been very up front about that all along. John, Shirley, These are NGS Monuments, NGS Data, People at the NGS help out here in this forum, and are not paid extra. There are 2 kinds of recovery and the FAQ itself explains this as such, and even specifically says that you can report to NGS yet are not under any obligation to do so. As for the not founds you find that were on the NGS, well good on you. NGS Surveyors traveled all of the US as crews, and rarely have a great deal of local knowledge about many of the places they work, crews were all temporary help in many cases, Seasonal or otherwise. They often worked northern states in summer and southern in the winter. Surveyors and other techs came and left so it is easy to me to see why sometimes they don't find something. Surveyors are not poindexter like robots, rather, many of them are going to be drinking beer on Friday after being handed their paycheck just like a lot of other people. If we cut them, they too will need a bandage. They will be the first to own up to the mistakes they make and the NGS does so for them all the time. They correct the errors graciously and go on. Maybe the not founds are something they did on a Monday or a Friday eh? Maybe when they were there things were different than now, and the station was somehow obscure? Maybe they cannot be any more sure of a find than we can, and so it goes. Beyond that there are over 1.5 million things NGS keeps Data on, where it be active or archived, and a lot had to be brought forth into the Data Age from paper and pencil. It was, and still is a human system and when they find the errors they correct them, further when other people find them they are gracious and correct them. The USPSQD is otherwise known as the United States Power Squadron. They are not a government agency. They are a non profit, club oriented organization that is basically centered around boats and boating safety. They elect people to run the club from their membership and they often volunteer to help in their communities nationally. One of their volunteer activities is to help recover survey markers and water boueys to the NGS and NOS. This is a 100% volunteer effort on their part by people who are not survey professionals. When they do not find something that you did, you are reading about a not find by someone giving up a Saturday or Sunday to community service, who often does not have a GPS, who is not getting credit or a score, and does not consider this their hobby. In fact, if I were to venture a guess, their hobby includes a Boat and on any given Saturday they would rather be on it. Can you blame them? As for ask Deb Brown? well that is a pinned topic just like the pinned one you have. She is an NGS employee, and able to field a lot of questions as the source for information. She is also the front line person who reads all the recoveries submitted to the NGS. Taken on the whole, if you look back through my posts here, I do not think you will find me parrotting " ask Deb Brown" a lot, though I may have referred someone to her when I thought it best. I also do not think you will find me asking the question of other posters, "when are you going to inform NGS". I leave that on the table as an option if people want, but I never pressure anyone to do so. In fact I think you will find that I say that there is no obligation to do so as a way of easing the pressure that sometimes seems to be there. You have a lot of finds between the two of you, yet I have never asked you why you have only done what you did. I figure you do what you like, of what consequence is what you do or don't do to me, I have no concern one way or the other. But if you ask me for help, I will help. If I ever come behind you in the field and recover a station you have, Please do not be offended, but I may recover it to the NGS. Not out of spite, but because I enjoy it. I am sure there are some who may say this, because they think it is cool. But everyone in the world comes from the premise of what they think is cool. So do you. You make no secrets about your love of rock hounding, yet you don't tell others they should do it too. But it is in your forum name every time you post and in your signature too, so you must enjoy that. I think that is fine. Not much different than say, putting a NRA or Harley Davidson sticker in the back window of a car, or advocating that reporting to the NGS is cool. Some people actually think it is cool, just like Harleys and Guns. I am terribly sorry about the NGS repetitiousness John and Shirley, But I cannot help but wonder how we could enjoy this hobby without the NGS. As it turns out, many many people here find the hobby and it's side aspects fascinating, and each in their own way. Again, I am reminded of all the Santa Fe Bench marks Colorado Papa found, along with the Supreme court and NGS state line boundary ramifications. And all the Indiana Vigo benchmarks that MRH is hunting which are not in the NGS database yet in this small world, we learn than another benchmark hunter and surveyor, Wild T2 was involved in placing some of those monuments. Wintertime has shared with us so many of the cool Disney benchmarks, even going to the trouble with friends to set up a website about them. The question was raised why these were not in the NGS database and why we cannot use them here. Zhanna was off on a hunt of 2 kinds when she and Rich found a USGS benchmark error not in the database, but pretty cool all the same, sharing pictures of the old survey documents, and DaveD who is the Chief Geodetic Surveyor of the NGS was instrumental in sorting out the situation. elcamano has brought a lot of cool pics, and info to the table and the story about the tech he knew who pulled and electronic caution sign through the the drive through at Mc Donald's. Maybe I am an industry insider and it was only funny to me! I still laugh over that. GeoTrailblazer is quick to hunt down anything that helps and came up with some great stuff on the artillery aiming thread and he helps us all a lot with may other things he finds. Oddly we find that Aiming a Howitzer at the enemy is something that was developed by the CGS and the Army. Jerry Wahl is a Surveyor who works nationally for the DNR, Here lately he has bee talking PLSS and old section work survey and how they seem to sometimes have an NGS connection and if this is regular... I could go on, and will in the form of reminding you both that you too have been great contributors here as well. Sorry, John, Shirley, The surveyors in the forum are not raising these great questions, Geocachers who benchmark hunt are and I cannot see how it is not serving us all to discuss it. It seems there is a little something here for everyone, from the Yukon Territories to the Mexican Border, to Maine and California. I learn from it too, and from looking at the numbers of readers, I have not seen any diminishment in readership based on the topic matter. If you feel other geocachers are not being served then I would like to begin by inviting them to join in. Show us your pictures, ask your questions. Do not be afraid of looking like a newbie or looking uninformed. None of us were born to this information, we had to learn it too. There is nothing here to fear other than seemingly the integrity of a find. Since it is so loosely defined, the culture of benchmark hunting which is a form of TPTB seems to have frowned on lees than accurate finds and this was on before I began posting here. But I have weighed in on where I come down on that and I know that there will be people sitting both sides of that fence. I am not afraid of discussing controversial issues in the hopes of lifting things up and making it better, and if not better, at least more defined. I am sorry you are not feeling served and am happy you chose to discuss it. Things go in cycles like bell bottoms and big hair. Perhaps even shag carpet and orange paint or wall paper will return to Vogue... Hopefully after I am dead and gone. Maybe something cool will happen, you never know. Either way, just like cars trucks and motorcycles, we all have to share the road, and I think you will find I have said that with no bones about it all along. Happy New Year, Rob

Hi John, I suspected you would feel that way, and expected you to weigh in on this as you have been more than clear about your feelings regarding rules and NGS recovery on several different occasions the past. So I made myself very clear. I feel that being very clear in our communication will suffice, as it is the best way to resolve all the grey areas we often find in this hobby. Surveying is full of gray areas and we prove this over and over here in the forum. I am sorry to hear that you are still disgruntled about the various types of recovery going on. The NGS is very happy that this recovery is happening by those who choose to submit their recoveries to them. It is making a difference in the quality of the data they can provide, as Geocachers are not only finding stations that have not been recovered in ages, but finding previously not found stations, notifying users of the database that land marks have changed or are now destroyed, finding errors, improving locational data on horizontally scaled locations, and finding minor errors in the datasheets that are being corrected. NGS has not only had Deb Brown very busy with Geocacher recoveries, but all the corrections to data Geocachers were finding caused them to assign Cheryl Malone to working on geocacher submitted data questions and error finds as well. Shortly after that the NGS assigned Casey Brennan, as a liaison between NGS and Geocachers. Dave Doyle, of the NGS has been helping Geocachers understand these monuments better for a few years here as well. So you see, it is just people choosing to make a difference while doing something they like. The NGS is acknowledging this and they know these monuments are not always simple or cut and dried. Since these geocaching, Groundspeak game pieces are NGS Monuments and NGS Data is used to play this geocaching game, I feel it is fair use of the forum on the part of both parties. Seems like a nice symbiotic relationship, not different than say the USGS National Map, the GPS and Amateur Radio forum, Cache in Trash out, etc. Interestingly, It is notable that we have also discussed PLSS BLM property line surveying here, Construction Surveying here, The Non Geocaching USGS stations, as well as the many kind of stations surveyors place which people commonly ask about, as to why they cannot find these in the Geocaching database. Then we discuss optional Mapping software, How datums differ, Benchmarks in other countries, and so on. Generally we have a great time doing so. I have never seen you or anyone else oppose those geocaching spinoffs, nor has any moderator closed any of these topics so why the rub with this? As an aside, Tennessee has been very forthcoming on several occasions, as to how much he enjoys this group and has been very hands off with us, so I am not seeing the problem. Geocaching and geocachers have found quite a number of ways to make a difference. Geocachers, of their own choice and volition have chosen to take all these things upon themselves. In this case they recover these monuments and do so because they want to. No one holds a gun to anyones head. I have always advocated that all are welcome and all are equally deserving of a good clear explanation of what these things are. I should think sharing, and the spirit of both types of recovery is a more than adequately fair use of the forum. Sure it has growing pains, but not any we have not handled well by being clear in our communications. In the most basic of ways, I have seen nothing short of benevolence here from all parties involved. Feel free to log here if you want John, and when people have questions, feel free to answer the way you think. You have shared some great insight and knowledge here in the forum and I hope you continue to. I share the same freedom as well as the enjoyment that you do. We are a part of this together. I said several months back when you made similar feelings evident with us at that time that I felt there is room to include everyone here and I still feel this way. If the way you feel is other, since your feelings as such always seem to occur in close proximity to mine, and you perhaps have feelings that are of a more personal and uncomfortable nature towards me and the way I choose to enjoy Benchmark Hunting and the forum, I invite you or anyone to contact me directly. If you don't, then I will presume you are ok with this evolution of the benchmark hunting process, as we take a positive view of it all while proposing options, and decide upon what seemingly may become commonly accepted practices. It seems like a democracy to me, and a very well mannered one at that. I hope you will continue to participate in it and continue the positive impact that you have already made. I like the feel of this myself and so I choose to lift it up and promote it. Beyond our differences, if any, which really aren't important to the forum on the whole, there are Benchmark hunters in the middle ground who have questions. They will hopefully read through all these answers to derive an answer that is a best fit for their question and make the choice they feel best for them in their hunting situation. It isn't about me, and not about you. I am just another point of view and I offer one from a Surveyors standpoint. Not the "be all or end all", just more information. In the end, I hope I am helping others access information that enables the best choice for them whether they are new at the game or a seasoned NGS recoverer. I hope they feel the answer is somewhere between all the various points of view. My intention is to try and answer their question, no matter what type of recovery they are trying to achieve. There is no stupid question, I like them all, it is all good to me. As always, Rob

Hey All, As to the Game I would think that if the game says, (ie any data which can be ascribed to the pid in the geocaching database, which seems to be the accepted practice) that the game piece is a station disc, and the station disc is found to be inaccessible then I would say you didn't find it, even if there is a plaque. Sorry. The game does say in many cases what you are supposed to be looking for. If you are not allowed to, or are unable to safely access the station, then you didn't recover it. If we want to make up our own rules fine, then everyone can, and the statistics will mean little or nothing. If we are forward thinking as a reader of this post then I am hoping we can imagine the anarchy of a game that is played by people who make up their own rules as they each go along. If our conscience is fine with it and other people disagree, then how we sleep with that is up to us as well. It may not be popular to say so, but I wonder what integrity there is in being too flexible. If we do not keep the standards reasonably high then statistics mean little, because what good are statistics if they can only be applied to a particular player? If we are so flexible, then what would be the standard to which we are to compare ourselves? How can we have a statistical breakdown for a game if we hold ourselves to different standards? Certainly flexibility is a good thing, and we should hold it high as an ideal when establishing a best practice, but once we have a best, established practice it is best that we go with the practice. What then would be the reference standard? Is it ok to bend rules just so we can turn a probable into a found? It seems to complicate matters more than it does for keeping it simple. To summarize this, how will we accommodate statistics for people who wish to claim a landmark find from the freeway at 60 mph vs the person who did bring a shovel and dig through a foot of topsoil to photograph a station disc. As a casual observer of relaxed rule making, who am I to believe went to the most effort to be correct in their reporting? Who's method of statistical reporting is the best so they can all be compared as apples with apples instead of apples with oranges? Even though we don't have to, many choose to claim only what they can photograph as proof rather than face the potential scrutiny. That really seems a simple solution to use as a guide. Can we show the actual object asked for by the data? As for the 911 Paranoia, I personally choose not to pull on superman's cape. Your milage may vary. I would rather have my initials in the NGS Database than become a recipient of a darwin award. Just food for thought is all. I am not making the rules, Nor am I trying to big deal it, I am just begging the obvious questions. When do we say when? Beyond this, I want to point out one little fly in the ointment. Geocaching benchmark recovery rules are WAY different than NGS recovery rules. NGS rules are what they are and are not flexible, as they own the database, most of the markers, and the way they want recovery done on their database, so there is no negotiating that. It is a system which is simple enough and it works well for them. Geocaching has established different rules for their game than those for NGS recovery, and they are not set in stone, so if you refer to this be sure to be clear in the communication that you are talking one or the other. (the two styles are different and can be comparatively confusing) TPTB has never really come down one way or the other, and Jeremy can be read many times over as being very open minded about rule making so the onus may be upon us as a group, after all, we here in the Benchmark forum are our own powers that be. We have already established some unwritten practices and follow them. In the forum, I have seen the different understandings become intermixed in a thread and cause tension over what is what. I would like to see others finding this hobby as fun as I have, and so simple, clear, and uncomplicated rules seem to work well. I know that not all people who ask a question about benchmark hunting have even heard of the NGS, nor do they really care. I try to see it as they may be seeing it and try to answer the question I think they are asking, but I have to be careful as I am as guilty as the rest for liking what I like. So try and be sure to differentiate which set of rules you are quoting your statistics for, as they are completely different animals. My personal conduct toward this situation is first, I recover for NGS recovery rules. (my choice) I try to establish recovery for them, then second, I decipher it to however the best fit for geocaching is or so seems to be. I have reported a lot more to NGS than to geocaching, but again I am only speaking for myself here and I am not advocating that anyone should follow in my footsteps. But if it makes a difference, NGS standards are High and My personal goal is to meet that first then see how it lays with the different options at geocaching. This will establish how I see things if it isn't obvious. Some may not care to do it this way and this is fine with me, as not all want to do NGS recovery, and that is cool. But you can be sure if I found it, I found the real object, I did not assume it should be there, because in my world as a Surveyor, I can't do that. (industry rules) It goes then that I personally choose not to on my own time. When it comes to the Benchmark on the ledge with a plaque, My sense is that many people will feel that the plaque is not the object and as such is not a recovery. We can think of them as purists, but they are within their right. Besides, what challenge is it to have everything be easy or so flexible as to be handed to us as a given? Seventhings has still made the best argument I have yet read for Landmark recovery. I will grant you that Landmarks like the Bunker Hill Monument, Space Needle, Washington Monument, and the Statue of Liberty are the real deal No brainer recoveries, and not worth nit picking, so whatever, I hope folks keep the integrity high when they log them. It would not hurt my feelings to think that you actually stopped by and paid the landmark a visit. Not a visit to the top, just the compound proper. Just a show of faith in the process of actually having been there, done that. On the Empire State Building, This is not taking the building as a landmark but rather as a station established upon the landmark. Assuming that we as a public are caged off from the actual location of this monumented disc triangulation station, then we cannot physically go to it and recover the disc itself can we? I am as sure it is probably there as anyone but I can't even get close to the top hat can I? I cant even photograph the top hat with my GPS in the pic, and it would not likely be ok to remove the top hat if I can't replace it as it was, If not then how can we recover the station by any other means other than by assumption, and if we allow this assumption as adequate recovery then what? We have to face the fact that some stations may in fact be there, recoverable under the right circumstances, but sometimes we are not the person who will be able to establish the right circumstances. As for all the other landmarks that are still seemingly there, and I am talking church steeples, stacks and water towers, etc, the integrity needs to be higher because if it does not have national or famous landmark status, nothing is forever. Seventhings recognized this and provided a very good method for recovery if someone wants to be that sure. Edited to add, the topic is; Can I log this? To which I ask, given the information on geocaching .com about this station, should you? ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ As to marks with an underground mark. I have used a number of these stations professionally over the years. Generally this was a practice used in the 1960's and 70's most often, and usually only when a first order horizontal (triangulation) station was being established. The station is completely adequate for use as the surface mark. It is the upper mark that was used to establish the station. Here was the order of construction: First the hole, Fairly deep to accomodate stacked stations. Then the underground mark was set, then some backfill and compaction, then the upper surface mark was centered over the underground station then more backfill and compaction, the reference marks and azimuth marks were established for use with the station. Once all the station pieces were set in the ground, A bilby tower was erected over a first order station and the instrument was properly centered to survey it in. Surveying in a first order station means long lines of survey to other previously established first order stations. During this era, the preferred Theodolite of CGS surveyors was the Wild T-3 Theodolite. Then no less than 12, and preferably 16 separate triangulations were generally observed complete with least squares adjustments to establish the geodetic location to very high accuracy, meaning accuracy to less than a half inch. The reason these stations were built this way was not just stability, because First order stations had to be established on ground with stability in the first place, but in that day, First order was the highest order, and it was Hierarchical. It takes first order stations to establish second and third order stations, these had to last and have high reliability. The primary reason for the subsurface station was not as much for stability because geologically if an area moves, more than just the top 3 feet are going to move. This will be based on the soil classes you are dealing with on an A, B, or C class. Class C is the most unstable and the most common. Generally, if you are having a soil problem at the surface, you likely have a soil problem with the entire section of soil strata at that location. There are many geological reasons for this. The Underground mark was established to save the station from ruin, or complete and total loss if the upper station were to be lost. These stations were the highest cost to CGS (NGS) to establish and the hope was this method will save the location if something happens to the upper mark, via construction or other man made situation. It happens. So yes, the surface mark is the station, the sub surface mark is the station too, and it is assumed that the sub surface station is there if the surface station is found to be undisturbed. Nobody digs them up to check. The underground station is for use if the upper station is lost only. I have put many $7-10,000 Trimble and Leica GPS and total station systems over these stations for many years and found them to be dead money accurate with the datasheet. GPS can reveal accuracy higher than many of these stations were surveyed to in their day and they are good. Very good. NGS overall does a very painstaking job. We all find little errors but a very good bit of that is data entry, not how well the calculus came out. In other words, more than anywhere else on the earth, when you are standing over one of these. You are Here. A and B order stations are GPS accurized and have higher order accuracy than optics could do. Those are the best out there. Enjoy, Rob

Holograph and Redleg, Thanks for the great work. It looks like we have 6400 Miliradians to create a highly accurate aiming circle which can pinpoint to 1 meter at 1000 meters distance, and a rectangular coordinate system that is grid based on NAD 27, the going Datum of that time, measuring the distances involved. They knew where they were on the grid, and what they wanted to shoot at. They overlay the Mil Circle with themselves as at the center, likely at scale so it could help ranging and dial in at less than one mill increments, then calculated how to set the howitzer angles based on how far they knew the shell would go. From there it looks like fire for effect and have a nice day. Based on the 8 meters that you got for difference at that location Holograph, using the NADCON program to convert back to NAD 27, the appropriate Datum for that station setting, I am curious if that will tighten up the unaccounted for 8 yards in the Datum shift. Do you see a difference? Mike was right in that the Feds always used Meters. I have seen the use of meters in survey going back forever, but It is interesting that the CGS and USACE used yards for this system. Did the source explain why yards were chosen, though it is obvious they later discarded that choice? It is obvious we are seeing the growing pains of a system which has evolved. That pretty much explains how the Army knew where they were on the ground at that Base, in reference to their grid system and how to orient themselves from there. And Wolves, you are technically correct about the system of metric measurement being a system adopted as a whole after World War two. However the meter itself was determined after a six-year survey ending in 1795, based on a line that ran from the North Pole to the Equator, via Paris which whose total length was determined and then divided by 10,000,000 (ten million) and is a unit which was determined to be 39.37008 inches in length. The name "metre" was chosen for this unit based on metron, the Greek word for "measure." Geodesists later learned they got this measurement slightly wrong, but they decided to keep it, as it was not very wrong and there had been a very large body of work already based on it. It also became the basis for other metric measurements in the metric system as well, and was the product of a postulation made in the late 1500's which proposed that there ought to be a base 10 system of measurements. Today, I can walk into a shopping mall and stand before the map in the food court and know where I am... It claims: You am here, and so it goes. But I still have a hard time finding a pair of pants there that does not have that extra meter of material which wants to hang to my knees. I guess we haven't solved all the problems... Happy Bombing, err, Artillery Shelling! Rob

Geo, If I may ask a favor, When you post this map, please just post a link to it here, don't post the picture. A million photos on a forum thread is a real bad use of bandwidth for all users. Downloads slow to an extreme crawl... I have had threads that will not load in 10 minutes. Please just put a link to your photos so if we want to see them, we can simply click the link and open it in a new window. Or not, if we so elect. Either way, one or two photos open faster on a separate link than a thread with 15 of them pasted up here... Thanks! Happy Holidays, Rob