ca_surveyor

I have a cache that I have been working on for about a year. I want to finish it up and get it going for Halloween..so the question is: I can make it quick and easy like WAITING FOR THE MAIL..or I can make it a bit harder like PLAIN SIGHT and make the reward fit the challenge. Either way, it will be a different cache (and hopefully fun to solve).. so, since most of you have visited both of these .. your input?? gil

I have been packing and hiking into the wilderness for many years.. and I have a lot of self confidence in what I do and how I will take care of myself and any others that come with me. This includes geocaching as well as any sport that puts you out of the general arena of contact. But, years of experience not withstanding, it is, I think, an extreme level of gross foolishness NOT to include a small cellphone as a standard pack item. Ignoring your own issues, what if you found an emergency that was time critical (say an unreported fire, or that infamous 'crack in the dam'. Back in the 50's it was great to send Lassie home to bring back mom or dad or 'help', but that was then and this is now. And if you are packing with others, it is definately poor planning and almost negligent on the part of all parties not to have a common phone should any of you become critically injured or disable. Even if you don't expect to be within cell service - you STILL pack one because you just never know until you need it - and then its too dadgum late. Ok.. so you say that you like to commune with nature and there is no place for a ringing telephone or Julie Andrews on a mountain top - Well I agree completely with you.. And it is just because of this reason that god, in her infinite wisdom, invented not only earth, sky, and water, but also the off switch... This pontification has been brought to you from California (go ahead - groan 'of course') by gil..

As someone noted, you will not be able to replace any benchmarks for reasons of both equipment and authority. Setting first order benchmarks (levels) requires some serious leveling equipment, some post processing headaches, and patience that tries most mortals.. Even if you have that, the qualifications generally demand a license as a land surveyor or a federal appointment neither of which is easy to get. Equipment.. actually GPS is never used for benchmark work. The relative accuracy of GPS for vertical work is measured in centimeters.. Precision vertical work is done in less then 1 mm. The equipment that was shown on the link, is called a Kinematic GPS system. The rover unit is shown and requires a second base or a link to a CORS system (public shared system sorta). With that equipment - as shown (hand held) you can expect to get horizontal values of a couple of hundredths and vertical accuracy of 2 or 3 CM's. The RTK (Real Time Kinematic) system costs about $20 to $30 k depending upon which bells and whistles you want.. Check out Trimbles web site for more exotic stuff. NGS... Last I heard NGS was no longer maintaining ANY monuments.. NOS (National Oceanic Systems) is, but if you are out in the middle of Nevada or Oaklahoma you are going to have to wait for the next 'big one' to get Ocean Front Property and new NOS disks. Ok.. I've been pontificating again.. sorry..

It is one of the aluminum markers that disney sets to 'subdivide' the areas of its park. I don't know if it is in a public record, but they used them exclusively on disney lands. The disks are made by Bernsen Int. for Disney and come in aluminum and brass. Since you are in Ca.. next time you go to the Disneyland in LA, walk up main street to near the statue of Walt.. look down and around along the centerline of the street.. there's a brass one there.. and a second one at the next plaza on the way to Cinderellas Castle. (An occupational hazard.. I tend to spot things like that and rememember them..) gi

Turning points are used in Level Circuits which, in turn are used to determine an elevation of an unknown point from a known one. If you envision a game of leap-frog, the first runner would represent the initial benchmark. He runs, places his hands on the shoulders of the second person and propels himself over , landing running a bit and then crouching and waiting as the second person now stands and begins running to repeat the process. The second person, while crouching could be considered the turning point Eventually the leap-froggers reach the end of the play area or tire out (the new benchmark). So, to put it into a survey perspective, level circuits are seldom single set-up processes. You set up the level (the gun), hold a tape on the known benchmark and read the difference (generally as a positive value since we usually find the known benchmark on the ground.) The person with the tape moves ahead to new point along the direction that you must go to reach the destination and places the tape there. The surveyor reads the difference and subtracts it from his running total, then grabs his level tosses upon his shoulder and marches past the man with the tape (or rod) and on toward the destination. (Here comes the answer.. get ready.. ok.. so now the second person, holding the rod or tape TURNS to face where the surveyor went to his next setup. And with that the process begins again (leap-frogging). and that, students, is a TURNING POINT. voila.. gil ca_surveyor

The crosses are placed, as Jeremy says above, to provide ground control for aerial photography. The crosses are placed, typically along some rough gridwork that the photogrammetry company defines based on the area to be mapped, the desired scale, and the altitude the plane will fly. Given that, the surveyors will try to reach a point within about 50 feet of the target, establish a point, or use an existing monument, and then place a cross on the ground. In the streets these are pretty simple. A can of cheap paint (so it doesn't last too long and blight the area and worse) and a brush. It gets more creative on a hillside or (my worst case, in a cow pasture..the cows kept eating the cross material). I have heard of once case where the plane was early and the last cross was not done. The surveyor and his assistant lay on the ground and each pointed at the survey point.. it actually worked (but they had to keep doing it each time the plane went by because they never knew if they were in the grid line being currently photographed). gil ca_surveyor (you got questions.. we got answers.. but do they match - grin)

Actually your hard hat is not a bad idea. Carry a clipboard (which is handy anyway) and even a red vest and you will automatically become invisible. As for the disk, remember that disks generally come in two 'flavors' monuments - which are placed to typically provide horizontal locations and benchmarks - which perpetuate elevations to some established datum. To be a monument, it must be physically possible to occupy that location with equipment (a transit, a tripod, a gps antenna..etc). Locations which refer to the 'pointy' end of a tall tower or structure are simply backsights or often called 'natural's. This means that the surveyor uses them to sight an initial or closing observation from another known point. To be a benchmark, it must reference a plane. This is done easily by setting it into a wall and making a measurement to that line that runs across the middle surface. So that disk in the Post Office wall is a benchmark. The surveyor or person running a level will simply measure up (or down) from the line to his/her sightline with a tape held against the building, and then continue with their work. voila... gil (ca_surveyor)

Actually your hard hat is not a bad idea. Carry a clipboard (which is handy anyway) and even a red vest and you will automatically become invisible. As for the disk, remember that disks generally come in two 'flavors' monuments - which are placed to typically provide horizontal locations and benchmarks - which perpetuate elevations to some established datum. To be a monument, it must be physically possible to occupy that location with equipment (a transit, a tripod, a gps antenna..etc). Locations which refer to the 'pointy' end of a tall tower or structure are simply backsights or often called 'natural's. This means that the surveyor uses them to sight an initial or closing observation from another known point. To be a benchmark, it must reference a plane. This is done easily by setting it into a wall and making a measurement to that line that runs across the middle surface. So that disk in the Post Office wall is a benchmark. The surveyor or person running a level will simply measure up (or down) from the line to his/her sightline with a tape held against the building, and then continue with their work. voila... gil (ca_surveyor)

I'll be down there again this winter and I'll set one up near the old lighthouse on the Pacific side..you have to take a 'tour' to get there (either horses or quad runner) but the 'tour' alone is worth it. (And besides.. how often have you gone hunting a cache on horseback..?) I'll bring a few 'bugs' for the other cabo caches too.. we'll see how far they travel. gil

I'll be down there again this winter and I'll set one up near the old lighthouse on the Pacific side..you have to take a 'tour' to get there (either horses or quad runner) but the 'tour' alone is worth it. (And besides.. how often have you gone hunting a cache on horseback..?) I'll bring a few 'bugs' for the other cabo caches too.. we'll see how far they travel. gil

In case someone ever walks up to you on a street and asks.. When you are refering to the brass/bronze/Aluminum disks or tablets.. Benchmarks measure UP and DOWN.. not position !!! Monuments reference position (and may have an elevation on them which also makes them a benchmark). I set these things for a living (does the collection in my living room count as individual finds??) and lastly.. locations you prob. didn't know about. If you have a City Hall built before the 70's there is generally a tablet at the front door. If you have a harbor.. look on the corners of the piers. Monuments are always set with long lines of visibility from one to another. Often these monuments are referenced on a document filed with the County Recorder - in California it is called a Record of Survey. Federal Monuments are exempt from that. 0k.. any questions? Otherwise good hunting. gil

In case someone ever walks up to you on a street and asks.. When you are refering to the brass/bronze/Aluminum disks or tablets.. Benchmarks measure UP and DOWN.. not position !!! Monuments reference position (and may have an elevation on them which also makes them a benchmark). I set these things for a living (does the collection in my living room count as individual finds??) and lastly.. locations you prob. didn't know about. If you have a City Hall built before the 70's there is generally a tablet at the front door. If you have a harbor.. look on the corners of the piers. Monuments are always set with long lines of visibility from one to another. Often these monuments are referenced on a document filed with the County Recorder - in California it is called a Record of Survey. Federal Monuments are exempt from that. 0k.. any questions? Otherwise good hunting. gil