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Bolt in place of a disk!(??)


patw

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RD2624 held a surprise for us. It is set with adjusted coordinates and our WAAS enabled took us right to the spot in an open park with 8 solid satellites. We averaged the coordinates for 15 minutes and got within the third decimal place of the minutes. No other bench marks were within 275 feet of the station. RM3 FULTON was recovered as a disk and which confirmed that were indeed, at the triangulation station RD2624.

 

Howsomever . . . . the NGS 1970 station description says THE STATION MARK, STAMPED FULTON 2 1970, IS A STANDARD DISK SET IN A 10-INCH SQUARE CONCRETE MONUMENT THAT PROJECTS 3 INCHES.

 

The 1994 USPSQD report merely says, recovered in good condition and does not mention the prescence of a bolt in lieu of the disc.

 

What we found was a 10-inch monument with a BOLT (!) embedded in its center (see photo in station description). This mark is located in a beautifully developed waterfront park with deep, luscious sod. The nearby road referred to in the description is no longer there.

 

Curious that the NGS data sheet does not reflect what would appear to be a major revision of the site. (?)

. . . . patrick & shirley

 

patrick & shirley

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Are you being diplomatic, Art? I'll concur that the photo seems to show the remnant of the monumented disk, with the post remaining only but the less-weathered outline of the disk clearly visable.

 

Somewhere not too far back elcamino or someone posted a link to a survey supply site. I found it educational to see what the disks looked like before they're monumented...can't find it again, unfortunately.

 

Max

Often wrong but seldom in doubt

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The description says that the mark is 2 feet from a metal witness post. Did you find it as well and are you sure this is not the post? The Survey disk that I've seen that were not yet set had a solid stem and this looks hallow like a pipe. I'll email you a picture of the disk that my supervisor has.

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patw -

 

That isn't a bolt. It is the shank of the disk. I've found 3 or 4 of these.

 

The point has been debated on this forum at length whether you could count it here on geocaching.com as either found, not-found, or destroyed. Surveytech has said that such a shank without its disk is still of some use for surveying, hence a find. However there's always some doubt that it was the benchmark in question since its label is no longer there (of course a "chiseled cross" has no label either) - hence a not-found. It has been severely damaged - hence destroyed. People take their pick on these.

 

I've seen NGS pages that say found - condition diskless.

 

For the NGS, send Deb a picture as stated on the NGS form. They will decide how to classify it.

 

For clicking, here is rd2624.

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Very well. I defer to the judgment and experience of both embra and trackers. Embra's point that it looks like a broken off disk bears credence in that, indeed, there appears to be an actual outline of the original disc in the less weathered stone surrounding the 'bolt'. I did not pick up on that on site.

No, there was no witness post. Fact is, I've found very few witness posts where they were supposed to be, especially the original ones from the NGS description. More often, there will be a new witness post set by local surveyors.

Thanks, gang, for another insight in the subject!

Curioser and curioser ....patrick

 

patrick & shirley

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Something does not appear right to me. That looks like a pipe, in a round concrete monument? Am I correct that the object is hollow in the center like a pipe? These disk are either brass or bronze, not steel. Is that brass? The shank of the particular type of disk is only about 1/2 inch in diameter.

 

Are you sure you have the correct position. Do not assume that the coords you have are correct unless you find the mark. It could be a coincidence that what you found is near the location.

 

Did you try measuring from the RM's and see if the distance checks out?

 

It is 46.808 meters (153.57 Ft) to RM 5

It is 83.247 meters (273.12 Ft) to RM 3

 

I think more research is needed before assuming the mark is destroyed.

 

As to why the datesheet does not reflect any current changes, no one must have been to it in years or else they could not find it.

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el camino, take a look at the Surv-Kap link above....Look under flarable markers and you'll see many of the standard disks are available with aluminum TUBING as mounts.

 

If this was an older marker, you might have something, as I dont know when they started using tubing as mounts, but this one was monumented in 1970, which is pretty recent for a marker.

 

The descriprion also states that it is a standard disk (which is usually 3"), mounted in a 10" concrete monument. If you look at the pic, if you figure that the circle is 3", the tubing looks like it could very well be 1/2", which I beleive is a standard size, also.

 

As to whether this is the mark or not, I agree with you in that if there are reference markers nearby, they should be measured or at least paced off to make sure this is as close to the original marker as possible. Then let Deb Brown know that this marker was found with a consumer grade GPS, and the that the distance/bearing to the reference marks were also checked this way.

 

Art

 

www.yankeetoys.org

www.BudBuilt.com

http://www.ttora-ne.mainpage.net/

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I wish I had some of those olds disks to photograph and show here. But I retired and all that stuff is in the possesion of my former employer (State DOT). From looking at the RM photo, that disk looks very familar to many of the later disks set in the 1960 and 1970, the last with the USC & GS legend. Of those that I have found, there is a small flat stem about 1/2 inch in size and 3 inch long brazed to the cap and that is set into the concrete post without any other metal.

 

It is very hard to determine scale from the close of photo and it would be a good idea to lay a 1 ft ruler etc next to the item being photographed for clarity.

 

I would not report that mark unless I was 100% positive I was correct in my assumption. I have seen way too many people mistakenly assume the mark is destroyed, only to go out and find the mark within matter of minutes.

 

I can remember one in particular. Our crew spent a couple of hours trying to find this Bench Mark. It was a mark we desperatly wanted to find because if it was not there, we would have to run levels (elevations) for about 5 miles farther (costly in manhours). The only reference that was left was the rr tracks that showed recent rehab. The other 2 witness's were a Mile Marker (that was gone) and a telegraph pole (that was gone). So one day after work the boss comes to my motel room and asks if I want to go take a walk with him to see if we prove the mark is gone. So we hiked about 1/2 mile down the tracks to the approx. location and proceeded to search for the pole and the Mile maker. I was walking along the woods line looking for the mile maker and found the oil sign, we measured ahead from there and found remnents of the old pole which was almost impossible to see in the brush. We then started digging in a location from these witnesses and found the bench mark almost 2 ft below the surface. The other guys never went into search detail that we did and thats why they erronously assumed the mark to be destroyed.

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Three of these disk-missing benchmarks I've found are dated 1956, 1958, and 1969, and they all have the hollow tubing brass shank.

 

It seems there's lots of different suppliers of benchmark caps, with only minor variations in topside appearance, but the shank styles probably vary much more.

 

The hollow design probably affords more friction against spinning and prying.

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At the suggestion of one of the big boys, I went back today and took a photo of a ruler laid across the monument from edge to edge. I also took a shot of the gpsr showing the averaged coordinates of the monument to establish that we were, indeed, at the correct mark. (Recall that there was no other mark, found or not found, within 150 feet and RM3 was already accounted for.) See RD2624 for the photos. . . . patrick & shirley

 

patrick & shirley

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It looks like you have the spot. The closeup without a reference gave a false impression of the size.

 

Its a good idea to use a tape measure etc to scale the photo's.

 

I would log is a poor, disturbed or mutilated. There is no way to know how the disk came to be missing, it could have been hit by some piece of equipment etc and the position may be questionable. Also, these are often the prize for souviner hunters. I have seen where a contractor uprooted the complete concrete monument from the ground. When we came back to the site several weeks later to claim the disk, someone had dug a hole and put the old conrete post back into the ground as if nothing had changed. We had to remove it. I also found a BM in a concrete pad for a memorial about 30 yrs back. About 1 yrs ago we needed a BM for GPS and I went back to the same location only to find the complete memorial had been relocated some 1000 feet to a new location with the original disk untouched. My boss and I went to remove the stamping on the disk per instructions from the NGS advisor only to find the memorial had been moved again but this time the bse broke and the had to construct a new one. We could not find the disk. This was at a local airport.

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