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Guess I found a gravity station! (Though that was nine years ago!) How do I check my other 800 benchmark logs to see what other types I have found?

I put this BM on my to-do-list after reviewing my country wide datasheets seach for this type of disk. On my visit-the-family up north trip, I made my way to GZ in west central NJ, driving in a light snow storm; I don't get to see much snow down here in S. Florida. This rare new style Gravity Reference Mark from 1937 was definitely one of the easiest BM's I've recovered, right on the side of the road. It looks like a couple of the forum regulars also visited this site a few years back. PID KV1610. A nice find for anyone Benchmarking or Geocaching in the area.

No, I didn't. I guess that I should have! I think I checked the real thing from NGS by going through the search page--I was going through a list and checking for those specifically. Do you think they updated it already based on my log? When going for these, I make a point of checking the real thing through NGS. But I can't swear to the fact that I looked on the NGS site...I think I did, though. If they updated the page based on my log, I would expect to see the recovery note by a geocacher at the bottom. Very strange! The moral of the story is, check the real NGS sheet, not just what's on gc.com...but I thought I did. From the gc.com link: LF1239_MARKER: DG = GRAVITY STATION DISK LF1239_SETTING: 7 = SET IN TOP OF CONCRETE MONUMENT LF1239 LF1239 HISTORY - Date Condition Recov. By LF1239 HISTORY - 1958 MONUMENTED CGS LF1239 HISTORY - 1975 GOOD USGS LF1239 HISTORY - 1977 GOOD NGS From the NGS link: LF1239_MARKER: DS = TRIANGULATION STATION DISK LF1239_SETTING: 7 = SET IN TOP OF CONCRETE MONUMENT LF1239_STAMPING: HIGHLAND 1958 LF1239_MARK LOGO: CGS LF1239_STABILITY: C = MAY HOLD, BUT OF TYPE COMMONLY SUBJECT TO LF1239+STABILITY: SURFACE MOTION LF1239 LF1239 HISTORY - Date Condition Report By LF1239 HISTORY - 1958 MONUMENTED CGS LF1239 HISTORY - 1975 GOOD USGS LF1239 HISTORY - 1977 GOOD NGS

I'm surprised that the data sheet archived on Geocaching.com shows it as LF1239_MARKER: DG = GRAVITY STATION DISK but the current NGS data sheet has LF1239_MARKER: DS = TRIANGULATION STATION DISK while the latest recovery is the same 1977 on both. Somehow the discrepancy came to their attention. Did you submit a correction to them?

I know what you're saying, Gungadoy! I went after what I was hoping was a gravity station in Iowa that hadn't been visited by the NGS in nearly 40 years. It turned out to not be a gravity station, but it really was a thrill when I dug the Azimuth Mark out of the mud, poured water on it, and it appeared before me. Now, the 2 marks had witness posts, so it wasn't a hard job to find them, still I really enjoyed being the first to recover them after so many years. There were only coordinates for the main mark, so I did follow the directions to find the Azimuth Mark. I would like to go after something with a full set sometime, maybe I'll buy my own economy metal detector in the new year! You might have to dnf a cache, but you know it's been found recently. I went 100 miles out of my way just to see if this mark still existed, and lo and behold it did! The drive and hunt were worth it! LF1239, recovered 8/24/15

I completed Gungadoy's challenge--it was a lot of fun finding the old, hard to find marks! Here's my state survey from Deland, Florida, and there are pics of the location, etc., in my log. It's AQ1245. I'm including my magnetic disc from West Virginia, HY0008. Gungadoy pointed out a Gravity Station reference mark in northern Florida, BE0315, and a Topographical Disc, AG1367 near Tampa--as he noted, it's tough to find one outside an airport. I used those to complete the challenge. I really need to get to California to get that last disc, the elusive Gravity Station!

The coolest and must visit of all the USC&GS disks, the Gravity Station disk. Took a trip to Las Vegas and made the short trip to Death Valley, CA to see this one. GS0206. Took the rental down the 35 mile gravel road recovering a bunch of CGS benchmarks along the way until reaching the Dayton-Harris BM. You need a GPS for this area. It was a mild 113 degrees at 200+ ft below sea level. An awesome day trip to consider if your in the Las Vegas area. Does anyone know where else one of these has been found?

The stamped elevation was probably within a fraction of a foot on the old NGVD29 datum, if the monument hasn't been moved. Since it's Geological Survey and not Coast & Geodetic Survey (predecessor to NGS) it might be a little looser than those on NGS data sheets. The stamped elevation could be different by several feet on the current NAVD88 datum - I haven't checked for the difference in that area. GPS of any grade does not measure elevations on either of those datums. It measures height above the mathematical ellipsoid model of the earth. That is typically several to many meters different from either of the elevations. Your handheld receiver probably has an approximate model of the difference (the geoid height) to give you a reading somewhat closer to the datums than the raw height measurement. Elevation isn't GPS's strong suit anyway, as you may notice by watching your reading wander around. Even surveyor grade GPS and the best geoid model isn't quite the same as NAVD88, but NGS is working on an improved gravity model that will let them replace NAVD88 within a few years. NAD83 is NOT exactly the same as WGS84, although the difference less than the typical repeatability of a recreational GPS so they treat them as the same. When WGS84 was defined, it and NAD83 were intended to be the same, and were to the accuracy that could be attained at the time. Now we know they are 3 or 4 feet different in the US, and growing further apart by 1.5 to 2 cm per year. Once you get to measuring things this accurately, it gets to be a headache to keep track of what you're measuring.

Maybe we can use them as an example when we appeal because a reviewer will not publish our listings with proximity, commercial, and railroad issues. Sounds like there were three strikes. Were the problems real or not? "Commercial" is debatable in some cases, but railroad and proximity are almost always clear cut. Looks commerical to me. This morning it made me want coffee and toast, now I'm ready for a craft beer. "Between Milan Coffee Works, the Mother Loaf, and Original Gravity Company. Residents are able to purchase handmade quality products. These three businesses are owner operated and offer phenomenal products. Milan Coffee Works roasts and brews its own coffee from raw coffee beans. The Mother Loaf bakery has the most amazing artisan breads around. Original Gravity is a destination for beer enthusiasts; all their brews are made in house and they offer a family friendly environment so everybody can enjoy. If you haven’t already tried products from these companies, we hope you will make a trip back soon."

Seems like it was a good event, and the CO is trying to re-activate them (I saw an Owner Maintenance log saying "activate" on several of the archived caches). But they don't seem to have understood the guidelines in several areas. I found the commercial aspect of GeoDay12: Milan Coffee Works sort of amusing, as it reads to me like an example that Groundspeak would put in the Knowledge Books to show what a commercial cache looks like. I can only assume either the text was changed post publication or the reviewer simply missed it. The text is below. Despite the private sector is underrepresented At Geocaching Day, these are three businesses that need to be mentioned. There’s something really good going here on County Street. Between Milan Coffee Works, the Mother Loaf, and Original Gravity Company. Residents are able to purchase handmade quality products. These three businesses are owner operated and offer phenomenal products. Milan Coffee Works roasts and brews its own coffee from raw coffee beans. The Mother Loaf bakery has the most amazing artisan breads around. Original Gravity is a destination for beer enthusiasts; all their brews are made in house and they offer a family friendly environment so everybody can enjoy. If you haven’t already tried products from these companies, we hope you will make a trip back soon.

I did a reply, I don't know why it didn't show up. Well, it was just two that I saw a picture of somewhere, they were NGS, not USGS. I tried by designation, but it didn't find anything. One was a gravity mark, one was a regular mark. I don't know the state they were.from.

That will be a ding for Hellfire And if anyone’s interested, this is when all the other events appeared in the games a. Tumbling a. Certain black-and-white era mat events (hands up callisthenics) had all the acrobatic verve of school gymnastics certificate six, which, I recall, featured skills as demanding as the 'forward roll' and the gravity-defying 'standing up'. Tumbling, however, was no such primary-school farce. American Rowland 'Flip' Wolfe took gold in Los Angeles thanks to his revolutionary backflip with double twist, only to see the event flick-flack off the floor and into gymnastic history. b. running deer shooting b. The men's single-shot running deer competition was one of 15 shooting sports events on the Shooting at the 1908 Summer Olympics programme.[1] A deer-shaped target made 10 runs of 75 feet, with the shooter firing one shot during each run. The runs lasted about 4 seconds each and took place 110 yards distant from the shooter. There were three concentric circles on the target, with the smallest counting for 4 points, the middle for 3, and the outermost for 2. A hit outside the circles but still on the target (except on the haunch) counted for 1 point. The maximum possible score was thus 40 points. c. horseshoes (throwing) HAS NOT BEEN AN OLYMPIC EVENT. d. club swinging d. Not in fact a night out for bored couples, but an event that involved swinging a club festooned with ribbons very quickly around the body and head, in a complicated routine. At the 1932 Games, American George Roth displayed a level of dedication seldom seen in the modern Olympic era. It was the Great Depression and Roth was unemployed and hungry. Yet he won gold. Seconds after being awarded his medal in front of 60,000 spectators, he walked out of the stadium in Los Angeles and hitchhiked home. e. tug of war e. Entertainment for West Country cider heads during the summer fête? Tell that to the ancient Greeks, renowned for their physical and intellectual stamina, who staged their first tug in 500BC. In modern Olympic rules, a team of eight had to pull the opposition six feet to win, but if no such drama had occurred after five minutes, the side who had pulled their opponents the furthest triumphed. London 1908 saw the sport at its most intense, when America were beaten in just a few short seconds by Great Britain. The unhappy losers accused Team GB, all of them policemen, of wearing illegal spiked boots, so we offered them a rematch in our socks ... and still stuffed them. f. under water swimming f. The men's underwater swimming was an event on the Swimming at the 1900 Summer Olympics schedule in Paris. The 1900 Games were the only occasion such an event was held. It was held on 12 August 1900. 14 swimmers from 4 nations competed. It was not featured at later Olympic games because of lack of spectator appeal g. 200m obstacle swimming g. The men's 200 metre obstacle event was an event in the 1900 Summer Olympics held in Paris. The 1900 Games were the only occasion such an event was held. It was held on 11 August and 12 August 1900. Twelve swimmers from five nations competed.There were three obstacles throughout the 200 metre course. Swimmers had to climb over the first two (a pole and a row of boats), and swim under the third (another row of boats)

Permethrin is synthesized from the natural insecticide in marigolds. That by itself wouldn't be enough to give me warm fuzzies about it, but from what I've read, I'll take that risk over the risk of Lyme disease or other tick-born infections. The thing is, permethrin is actually a toxin to ticks, not merely a repellant. I have put live ticks on a piece of fabric inside of a circle that I had soaked with a DEET-based repellant and had them totally ignore it and walk right through it. If they tried that with permetrin-treated clothing, they would be dead. Wikipedia's entry on human toxicity of permethrin: https://en.wikipedia...#Human_exposure I'm just not keen on putting stuff like this on me. I have no idea what long term effects permethrin might have and i'm fairly certain no one else does either. I'll take my chances with the ticks. We just got back from an Arkansas trip where we hiked trails in some of the state parks. Needless to say, ticks, red bugs, and poison ivy were everywhere. Picked up plenty of ticks, have a teensy bit of itching from the red bugs, and so far, haven't had the pi break out. I figure this is just part of the overall experience. Have you known anybody that had a long-term case of Lyme? I have a friend that had an eye bulging out of its socket. I've known people that didn't go outdoors for years because of it... it hurt to move. It is some baaaad stuff. Suit yourself, of course, but know the risks. Long term effects of Lyme are well-known. I had a girlfriend who got Lyme and it messed her up so bad she ended up (along with other problems) Killing herself. The pesticide is much better then Lyme disease for sure! I have been doing pest and termite control for almost 17 years. I am in no way chemical shy but also have a bunch of exposure to it. That is the reason I don't really see myself wearing Perethrin soaked clothes. I am sure if you soak it in the stuff it would take more heat then a dryer to break it all down but was just trying to figure out what the OP might be worried about. For myself for tick control I spray my boots and outer pants with some deet spray before caching somewhere I think there might be ticks. If I know tick are there I might spray more of my clothes. Good point about boots. I also treat my boots with permethrin. You had a girlfriend that ended her life, you believe in part to Lyme disease, yet you resist the only effective known deterrent? Deet simply does not slow those parasites down. You can't repel them... they aren't smart enough. DEET works by messing with your CO2 signals when it comes to mosquitoes, but ticks simply climb upwards. To the top of grass, to your chest. CO2 doesn't seem to have as much to do with it as gravity does. The long term tests are in: Lyme: Extremely serious. Permethrin: Unknown. Of course, you may never be bitten by a Lyme (or Rocky Mountain Fever or other tick-borne disease) bearing tick if you wear Permethrim-treated clothing every time you're in tick country. So it really is impossible to weigh the risks completely. But me... I'm gonna take my chances with the marigolds.

Het valt mij op de reviewer Neon Tetra meerdere caches heeft gepubliceerd die op te korte afstand van een andere cache zijn verwijderd, binnen 161 meter, en soms zelfs slechts 25 meter. Kent deze reviewer de regels niet of kan me vooraf hem toestemming vragen? ik heb ook leuke locaties gevonden die ideaal zijn voor een leuke nano, maar op 100 meter ligt er al eentje van iemand anders, dus ik zou dat ook wel willen. (maar of het nou echt de bedoeling is om op elke hoek v.d. straat een cache te plaatsen vraag ik me af). Overigens; stel nou dat een reviewer een fout maakt, word een cache dan alsnog gearchiveerd of heeft de maker ervan gewoon mazzel gehad ? p.s. 'Geo-Gravity' ik ben ook caches tegengekomen die door jou zijn gepubliceerd en ook niet voldoen aan de regels, zoals GC49JZ3 Moord op de tennisbaan. Verdachte 1 , welke op te korte afstand van een andere cache ligt. Of geld de 161 meter regel niet voor Mystery caches? (daar zijn de guidelines niet helder over namelijk)

Ditto what mloser said. Some background in more detail: The list of data sheets includes four kinds: 1. True bench marks, i.e. vertical control marks having ADJUSTED elevation and typically loose coordinates. 2. Triangulation stations, having ADJUSTED coordinates and typically loose elevation. These were occupied with instruments to take sights to other points and are the most accurately known among the "classical" control points. 3. Intersection Stations such as spires, tanks, towers, and chimneys. These were not occupied, but were sighted upon, mostly as a check on the data for triangulation stations. This gave them pretty good coordinates, but not as well-checked as the triangulation stations. 4. More recently, stations measured by GPS. The horizontal is great and the vertical is not in the same measurement system as the classical bench marks. There are also a few older stations serving both horizontal and vertical purposes. Elevation bench marks are still of great importance, at least for the next several years until NGS puts out a new GPS and gravity-based vertical datum, and it is adopted by all users, including the national flood insurance program, the Corps of Engineers, and cities that haven't all moved even to the current datum. Triangulation stations are of decreasing importance due to widespread use of precision GPS, but still are of interest to NGS. Intersection stations are a.) less accurate, b.) often moved slightly over time by maintenance and nature, and c.) not readily occupied by GPS to allow future use, so NGS has pretty much given up on them. ---- The lack of intersection stations in your area could be due to you not having any stations of the triangulation network in your immediate vicinity. The elevation and coordinate surveys were essentially independent. Each network was a fishnet mesh stretched across the country and sometimes the holes were 20 miles or more wide. The networks generally don't coincide. The stations were chosen by different criteria. For vertical (elevation) work you want nice clear sight lines for 300 yard/meter increments, and as few hills as practical. Thus they frequently followed railroads and roads. For horizontal coordinates, you want to see as far as possible, from a Bilby tower if necessary, so stations were placed on the higher spots available and several miles apart.

Een geocache zal nooit uit het archief worden gehaald om ter adoptie te worden aangeboden. Geo Gravity Volunteer Reviewer voor Vlaanderen

Add 24 foot long pole with hook on end( painters pole 8 foot three sections) UV flashlight, hacksaw blade, Anti gravity boots In general anything that you can dream up. There have been a few times I wish for them boots. The insanely high 40 foot micro in a pine tree.

Mike and Linda, I stumbled across my first benchmark in early 1962. It was (and still is, I believe) located in the top of a railroad bridge abutment a few hundred meters from my home. It was a true "benchmark" as it had an elevation listed. During my next trip to the public library I read as much information as I could find about these objects. I was fascinated by the idea that precise location and elevation amsl could be determined by scientific instruments. I regard that discovery as one of several events in my young life that led me to a career in science. Over the years I have delighted in the occasional chance discoveries of benchmarks. The relatively recent availability of searchable databases/digital tools like the National Geodetic Survey Data Explorer and the Groundspeak listing have made hunting these structures much more practical. I even have an app on my smartphone now! In the last few years I have read much more of the literature that is available on the history of these marks (I was fascinated to learn that the reason that so many of the controls in my area were monumented in the 1930's was due to public works projects intended to keep surveyors and related personnel employed during the Great Depression.) I have also discovered that there are many purposes for what we commonly call benchmarks (I found a magnetic control this year and I hope to find a gravity station in 2015.) Science, history and interesting objects...what more could you ask for? Mike P.S.If you do go hunting benchmarks, take the kids.

Even though it may be taking the game too seriously, the cache should always be replaced as found. I enjoy the challenge of high terrain caches, and on more than one occasion I went out to look for a tree climb cache only to be disappointed to find it at eye level or on the ground under a pile of sticks. It's the same feeling I get when I'm watching a good movie on tv and the ending gets preempted by a 'breaking news' announcement, or buying a newspaper and finding that someone thoughtfully 'borrowed' it, did the puzzles, clipped a few things, and put it back on the rack. On the other hand, a cache owner who hides a cache up in a tree like that should secure it so that it cannot be knocked out of the tree. It is not that difficult to create a tether or clamp that will hold a cache in place without damaging the tree. And it helps to hide the cache high enough that a stick isn't going to knock it out of place. When I find a tree cache that is obviously out of place, I try to put it back where it should have been if at all possible. I check cache description and logs for how high, look for pictures, look for obvious clues like a loose tether. Failing that, the cache is liable to end up even higher than the original placement. I got a late start in tree climbing because my Mother was very protective, but to her dismay, once I got into trees I climbed everything I could. I climbed well into my teens, and slowly tapered off from there. I don't climb anymore just for the joy of it. It isn't fear of heights that did me in, but an aversion to gravity.

Good elevation bench marks are still important to professionals for at least several more years. NGS plans to complete their GRAV-D project and release a new vertical datum that will be based on GPS measurements with adjustments from the gravity data. Until then, GPS can't give accurate elevation data of the kind (orthometric heights) established on the passive bench marks. And if you understand just a little bit about what the marks represent , the difference between SCALED and ADJUSTED, use common sense and caution, and follow the examples of prior recovery reports, you can still make worthwhile contributions by reporting finds.

Recovered a cool Gravity Reference Mark in North Florida, BE0315. The last one I tried to find had been recently taken from its monument.

Cal baselines are ONLY for distance, and have no better lat-lon than is needed to find them. http://geodesy.noaa.gov/CBLINES/calibration.html The best available for absolute lat-lon are HARN or CBN stations with GPS coordinates. First order stations may be as good relative to other nearby ones, but not relative to the world. If he's interested in that level of accuracy, he must develop a very good understanding of datums, the flavors thereof, and what those imply. If this is somehow astronomically related, he needs to know that astronomical latitude and longitude will probably differ by up to hundreds of feet from GPS lat-lon due to variations in gravity, which pull the local vertical away from the normal to the ellipsoid, so it will in general not point to the axis of the earth.

The key is the Order of the stations, as shown on the NGS data sheets. For older measurements, this will be the relative accuracy compared to other stations in the area. For newer, GPS derived, data they may give both the local accuracy and the accuracy relative to the world as measured in the NAD83 latest refinement. Try to use First Order stations. Is the student just needing a distance, or is lat-lon also critical? How far apart should they be? The most accurate distances, maybe down to a millimeter, are for calibration baselines, of which most states have at least one, although some of them (like the one nearest me) have been allowed to deteriorate. Baselines often go out to near a mile. On the sidetrack of vertical accuracy, there are two problems with GPS elevations. The first is that since you don't have satellites both above and below the accuracy is poorer than for horizontal where you can have satellites in any direction. The second and more fundamental reason is that GPS measures a different kind of elevation than does optical leveling. Optical leveling follows the surfaces of constant gravity and measures with respect to the theoretical "sea level" geoid underground. GPS has no knowledge of gravity and computes the elevation above the mathematically perfect ellipsoid model. NGS is working on the conversion between systems by getting more gravity data in the 10-year GRAV-D program.

That's the same thing that Nira mentioned in post #9 and explains a lot of what I've noticed. The only other way that basalt can interfere with a compass is from a gravity induced impact. I love the gravity induced impact as a method of interference.

That's the same thing that Nira mentioned in post #9 and explains a lot of what I've noticed. The only other way that basalt can interfere with a compass is from a gravity induced impact.