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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

Er zijn enkele opties: Indien het caches zijn die voor een event bedoeld zijn, HOLD"naam event" cachenaam. Als wij de caches zo binnenkrijgen kunnen we een saturatiecheck doen en de eventuele opmerking overmaken na een eerste screening. Indien het een reeks is die niet voor een event bedoeld is, zet je gewoon in de reviewernote de gewenste publicatiedatum en de vermelding dat de reeks in zijn geheel moet gepublished worden. Wat we dan ook doen is als er in een van de caches een probleem is we de hele reeks disable zo dat er zeker geen losse caches gepublished worden. Als alles dan in orde is bied je ze gewoon terug aan ter review en doen wij de integrale publish. Hopende je hier een afdoend antwoord geven te hebben groeten we je George Gravitalis Geo-Gravity Groundspeak Volunteer Reviewer voor Nederland en Vlaanderen

GoldBugGirl and Gatoulis, Both of you did great in figuring out my coin's message, so you will both be getting a free coin when they are done! I will contact you when they are ready. Here is my explanation: Front - The word at the top is "Habakkuk" written in Hebrew. The building is the Great Ziggurat and represents the Babylonian Empire. The background image is a war horse and a chariot wheel representing the Babylonian war machine. The text is from the first chapter of Habakkuk and is perhaps as relevant today as it was when it was first written. The idea in Habakkuk is that the the people of Judea and Jerusalem had become unjust and cruel. The Babylonians were used by God as a tool to bring an end to the corrupt Judean government. Back - This side of the coin shows a heart and feather being weighed on a scale. This imagery is well known from the Egyptian concept of judgement in which the heart of a person is weighed against the feather of Maat (truth). The balance shows that the person (most likely an influential citizen of Jerusalem) is weighed down with sin. The imagery also comes from the book of Daniel in which the king is told "You have been weighed on the scales and found wanting." The text at the bottom says "sun and moon stood still in the heavens." The top of the scale shows the sun and the moon in an eclipse to give gravity to God's judgement. The text in the background is from Habakkuk chapter 3. I chose to make this coin simply because almost no one would ever choose to feature the book of Habakkuk in anything. I just wanted to breath new life into a neglected passage from literature. In truth, I don't expect the average person to have any idea of what the words and images mean, I want a person holding it to find it compelling and mysterious. The text on the front is meant to be ambiguous, but giving a sense of expectation. There were some hold-ups in getting this coin minted, but now it seems to be going forward.

Welkom Geo-Gravity en Sus Antigoon. Ter info: ik heb jullie aankondiging ook gepost op het Geocaching.BE forum (link)

Hallo Belgische geocachers, Mijn naam is George Gravitalis. Ik ben een aangename belg met griekse roots. Sinds kort ben ik het Nederlands-Belgisch reviewer team komen versterken. Zoals mijn collega's reviewers stel ik mij vrijwillig ter beschikking van de geocache-community en zal ik mijn uiterste best doen om jullie geocaches op een zo goed mogelijke en snelle manier proberen te reviewen. Zoals verschillende onder jullie al zullen gemerkt hebben, en ik zelf ook, ben ik bereikbaar via volgende kanalen om op al jullie vragen te antwoorden. Twitter: @Geo_Gravity Mail: geo.0.gravity@gmail.com groetjes George

Hallo Nederlandse en Belgische geocachers, Mijn naam is George Gravitalis. Ik ben een aangename belg met griekse roots. Sinds kort ben ik het Nederlands-Belgisch reviewer team komen versterken. Zoals mijn collega's reviewers stel ik mij vrijwillig ter beschikking van de geocache-community en zal ik mijn uiterste best doen om jullie geocaches op een zo goed mogelijke en snelle manier proberen te reviewen. Zoals verschillende onder jullie al zullen gemerkt hebben, en ik zelf ook, ben ik bereikbaar via volgende kanalen om op al jullie vragen te antwoorden. Twitter: @Geo_Gravity Mail: geo.0.gravity@gmail.com groetjes George

Training was good, Frogfoot1 have a nice holiday. I'll make you proud. @Geo_Gravity geo.0.gravity@gmail.com

Or ... how about if we just stop complaining, period? We know there will always be people who don't expend the time, effort or expense to fill caches with "nice" stuff. It's a fact of life. Complaining about it is sort of like complaining about gravity. I get so p***ed off when gravity holds me to the earth and I can't slam dunk a basket ball.

Thanks for talking me down, I just wanted people to understand the gravity of the situation. I didn't want to launch another controversy.

Actually it wouldn't have to be that heavy (approx. 1/6 gravity, you know....). Actually, wouldn't it have to be 6 times as massive in order to be the same weight on the moon? Got to think about that one... BUT at least you could ignore WIND loadings on the pole. Amongst other factors. Scrabblers: It depends on what satellites and for what purpose. GPS (Earth system) would not be good at all. They broadcast towards Earth surface and are so distant that the signals would all come from the same place if they could be received at all. A Moon based MPS nav system would be OK. Doug 7rxc

Oh! You've been reading what I've been into lately. I didn't know there was a SA article on it! I'll have to read that. I have sent off a short article to Today's Cacher on that very topic. Yes, the speed of the sats cause a 7microsecond slowing compared to clocks on earth, but gravity causes a 45 microsecond slowing compared to clocks on the sats over the course of a day. If left unadjusted that would cause an error of 38,000 nanoseconds, or 38,000 feet of postion error over the course of a day. Special relativity says that clocks will tick slower at speed, and general relativity states that clocks will tick slower in a gravity well. A clock ticks faster on a mountain top than one in a valley.

Actually it wouldn't have to be that heavy (approx. 1/6 gravity, you know....). Actually, wouldn't it have to be 6 times as massive in order to be the same weight on the moon?

Actually it wouldn't have to be that heavy (approx. 1/6 gravity, you know....). Of course, having a cache on the moon would have its advantages....you could use anything at all for a cache container as water intrusion would not be a concern...no more damp logs!

No real question here, just passing on things I have been reading. If you know about this topic please add to it. Can you imagine the complexities involved in the GPS system? General relativity states that clocks tick slower the nearer a gravity source it is. Clocks on Earth are slower than one in space. One on a mountain top is faster than one in the valley. Yet Special relativity states that faster on moving bodies the clock will tick slower than on slower moving bodies. One traveling in space tick slower than one on Earth. Thus the atomic clocks on a GPS satellite traveling at speed will tick slower than one sationary on Earth, BUT, atomic clocks on a GPS satelllite in weightless space will tick faster than than one in the gravity well of Earth. These 2 factors do not cancel each other out, but obviously they do to some extent. Yet there are other factors! The Earth spins! This plays a part in relativity as well. Eliptical orbits cause havoc in figuring out the relationship of relativity. Tidal potentials of the moon and sun, which are not always a consistant distance away. What elevation are you at with your GPS? There is a lot that goes into this! Nanoseconds are important! Nanoseconds mean being off of your correct position by meters. Of course correction are figured out and made. They use the Earth's geoid at mean sea level as the position to correct these relativistic errors to. The corrections are in the order of about 2.4 meters, but I'm sure it must be ever changing. But can you imagine what a mind bending thing to figure out all of this ! And it is only a small fraction of what goes into the GPS system.

Two logs that made my day. The first isn't even my cache, but it is so cool that I feel compelled to repeat it here. "FTF!! But, OH what a day it was. Started the drive in on Telegraph Canyon Rd, Then on to Ajax Mine Rd. The driving was fairly easy going in my Tacoma. Got to the Orphan Boy Mine Rd turn off to head South, and my concience told me to stop there and hike the rest of the way. I've never been one to may much attention to that little voice in my head. so I drove in a ways. Not too bad. Found a spot to park, and walked the last 1/4 mile or so to the cache. Found the cache easily enough and signed the log. Took a few pictures, then headed back to the truck. This is where the day starts getting interesting. On the way out towards Ajax Mine Rd., I got the left front tire caught in a runoff wash out an the side of the road, as I was just getting the tire clear of that, I felt the left rear go over the edge. After that, it was gravity that took over, and I could'nt do anything about it. As the tires caught during the siways slide, over she went, finally landing on the roof in the creek bed. After kicking out some of the already broken glass, and getting out of the truck, I checked my phone, and I had NO cell signal, and an almost dead battery. So I fished my pack out, and a few other belongings, marked a waypoint for the truck, and headed up the road to a high spot, about 1 1/2 mi, to try and get signal. Called 911, gave them my coords, and waited. After about an hour and a half, and no sign of help, I called 911 back, and stayed on the line with them. About 15-20 min later, I spotted the DPS helicopter. After they finally found a spot to land, they loaded me up and flew me into Superior, to be met by an ambulance. I did not realise how banged up or injured I was, or could have been, because of the adrenilan rush I was on. Once in superior, it was decided that it would be best if I was flown to a neurological trauma center. So, I got a second helicopter ride to Scottsdale. Fortunatly, nothing was broken. Just beat up a bunch. And the let me go home after a few hours. Now we just need to figure out how to get my truck out of that canyon. 2008 Toyota Pickup Truck (Totaled) - Close to $30,000 Medical bills/LifeFlight Fees - close to $30,000 Vehicle Extraction/ Towing Fees - $4,800 Getting the FTF and a Smiley - Priceless Took - nothing, Left - nothing(except my truck, in the canyon) and signed the log. Dipping my personal TB for the mileage and the adventure. This will most probably be my MOST MEMORABLE cache ever. Thanks *Update - June 1, 09* The truck has been recovered. It took the towing company 10 hours, 3 guys, and 3 trucks. They could not get the 24' flatbed in anywhere near, and had to upright it, and drag it out with thier huge 4wd truck." The second is on one of my caches. YOu have to feel good about one like this. "Well my hat is off to you. I can officially crown you owner of the most and best views from caches in Payson!!! I left at four this afternoon and came off the hill in the dark. The hides were absolutely brilliant. Great first container! The last hide is wonderful. I am glad you and I think alike. I walked right to the only large cedar I could find on the east side of the ridge, climbed around sat down and said " hmm- iwould hide a cache right here." Amazingly that is right where it was. The rock placement for camoflage was absolutely incredible. I placed them all back with exquisite care because I can appreciate the effort it takes to find and arrange those rocks just so. Found a rattlesnake in the dark on the way out from the final cache, luckily he sang REALLY loud so he saved us both from a miserable afternoon. Moved the TB from stage three to stage five. I must have missed the other TB. Don't know how, but did not see it. I was in a real hurry a stage four, so I might not have seen it. Can't say enough about what an amazing series this is. Lots of work and scouting. I always love the ones on top of hills and mountains and this does not disappoint. The sunset was beautiful and the bulls were bugling like crazy as I went after stage 5. What a great day caching. Thanks so much for this multistage- Probably the best Payson has to offer! T: Coin out of Stage 5 L: TB from stage 3 to stage 5. Thanks again!"

Wow! Stu and Sandy aren't afraid to jetski even in the most dead defying places!

I believe that the down hill pains are because gravity increases the impact on your movements so your joints and muscles recieve more stress. Climbing uphill is more tiring because you are fighting against gravity but you dont get the same impacts.

The Colorado uses SD not microSD memory. You must push the SD in a little to click and release. The SD will not simply fall out just by gravity. Your SD slot is defective if it will drop out on its own.

Spoo - I saw you have benchmark finding activity in Cumberland and Oxford counties. So, I used those two in DSWIN and found this about the Disk Types: For Cumberland County (534 PIDs): Type Number of PIDs DB 158 DD 122 DH 1 DJ 8 DO 60 DR 27 DS 36 DT 1 DV 1 For Oxford County (315 PIDs): Type Number of PIDs DB 126 DD 66 DE 1 DH 1 DO 49 DR 6 DS 2 DV 2 DZ 4 From the Hippopotamus file, the Disk types (among all the other types of marks) are: DA Astro pier disk DB Bench mark disk DD Survey disk (other agency) DE Traverse station disk DG Gravity station disk DH Horizontal control disk DJ Tidal station disk DK Gravity reference mark disk DM Magnetic station disk DO Disk not specified (see description) DP Base line pier disk DQ Calibration base line disk DR Reference mark disk DS Triangulation station disk DT Topographic station disk DU Boundary marker DV Vertical control disk DW NOS hydrographic survey disk DZ Azimuth mark disk

Not anti-inertia either. To be honest, this book was published in 1928 and so well before the stuff it attempts to describe were understood. The mechanism for transmitting the power is very loosely described. Some of that description borders on gravity, but it's more than just gravitational attraction. That said, I'm after just the source of power rather than the mechanism by which that power moves stuff. To make this fair on those who're not familiar with E.E. Smith, I'll mention that getting the answer by reading the book is not cheating, and that some of the Skylark series are available as free eBooks. They can be downloaded in a variety of formats from http://manybooks.net/authors/smithee.html (among others). BTW, I loved the Lensman series when I read them decades ago, but I haven't been able to find more than Triplanetary as an eBook and so I might be a while before I get around to re-reading them!

Not anti-gravity, so anti-inertia? I've only read the Lensman series by EE., not the Skylark books.

I've started using GS's geo app since c:geo stopped working as it used to. I thought it was the bee's knees to start with but i've since found a few foibles with it, but it does the job almost as good as c:geo used to do it. At least now it's a purchased app there is some gravity gained regarding requesting updates etc. at least i hope!...

Is this a find or not? The NGS provided two different location descriptions only 6 months apart! Perhaps the real station is in the former spring area that's now sealed with rocks and cement. The hexagonal disk is old but has no date. Did the Coast and Geodetic Survey use hexagonal reference disks for gravity stations? Current gravity stations are circular with a 6-pointed star insignia, probably symbolic of the older hexagon disks. What does the arrow point to? Is it official? I figured the matching ledge on the other side of the spring would be the location of the benchmark disk F 95 mentioned (with 1/3 of it missing), but the ledge appears to have never had a disk mounted there. Does the arrow point to F 95? It seems odd to place disks in a man-made rock wall. A very mysterious place ..... so far. It would be interesting to see the Coast and Geodetic Survey's original description of this station.

The mark is an official USC&GS 'Gravity Station Reference Mark', shown as item #6 in Figure 49, page 85, of the Manual of Geodetic Triangulation, Special Publication No. 247. According to the same page and figure, 'Magnetic Station Marks' are circular with a 6-pointed star insignia in the center. Only the 'Gravity Stations' are hexoganal. BDT, it definately is a confusing find. I would think that if you found mark as described in either of the NGS entries you could probably count it as a find. An inquiry to the NGS about the two 1998 reports, or a newer report to the NGS might be in order. (If you found things as described in both 1998 NGS reports, you could probably count it as two finds. Just a thought.) - Kewaneh

From all I can see that is a USC&GS gravity station disc and from what I can read in your photo it appears to match what the datasheet claims is the stamp. the arrow I'm not to sure about. Check out Zhanna's web page. She has there some outlines of station marks used by USC&GS for various sites. Nice find though. Had a chance to check some refs. and found that your mark is a standard USC&GS gravity station reference mark disc. Sorry for not researching prior to posting.