elvis3068

Just a side bar to all this: A "fire plug" in its original meaning could not have ever been a benchmark. The term goes WAY back in time into the 19th century when water supplies set up for city fire departments were wooden piping that ran just under the surface. When the horses got the apparatus to the scene, the firemen would then "plug" into the wood with a cylindrical metal end hammered in place, that would give them water under pressure to work. There were no fire hydrants as we know them today since the piping was all under ground.

USGS certainly did use aluminum in early disks going back to around 1900. Search for some threads and you'll find a few discussions of this. Here's one I recovered (circa 1900) that is both flat and aluminum. PE0518 That certainly is a very similar disk to the one we saw in Nashua. I would be very confident to say that it was aluminum at this point. Thanks so much!!

. What metal did you think it was? I'm a chemist, so I'm used to looking at matter critically. I thought it was either aluminum or a nickel alloy. It did not have that bronze "tinge." If the USGS HAD used aluminum, I would think that would be a possibility. Aluminum oxide is white and there was some traces of that on the marker.

Looking to expand my background knowledge with a few questions. I was in downtown Nashua, NH for the first time this weekend. I came across a Civil War Monument and thought (correctly) that there would be a benchmark (MY0449). http://bloomsburgasd.schoolwires.com/62822...47/IMG_7130.JPG http://bloomsburgasd.schoolwires.com/62822...47/IMG_7136.JPG I have a few questions for those of you more in the know than I: 1.) Should this benchmark be considered destroyed due to the obvious damage? The mark is flat and not bronze. 2.) What kind of metal did USGS use for their benchmarks (probably) prior to the 20th century? 3.) About what time did the benchmarks change from being flat? Thanks for any info/insight you can give. I do enjoy reading this forum often.

OK, thanks for that info- it is very helpful. I will do that.

OK, thanks for the input....I agree it does look more like a "5" than an "S." I may well follow up (if I get a chance) somewhere down in Northumberland. Thanks.

I was in the town of Northumberland, PA recently and had free time to walk around and look at a town I had never visited before. I saw a small, old bridge in what is a back alleyway (Touliman Ave) in the middle of town. I looked to see if there may have been a benchmark and, sure enough, there was a chiseled square. The coordinates are 40' 53.571 and 76' 47.401. The bridge is in decent shape, but you can tell it's been there a while. Can anyone tell me where I can go (if anywhere) to find out when this was monumented?

Dave, This is a very cool picture of this instrument, thank you. I can follow your explanation a bit on charting relationship of pairs of stars, but is 105 observations a random number chosen, or does it hold some mathematical use. (I'm a chemist, so be patient with me!!) td

That is what is known as an "Astronomic Station". The double monument was for mounting an instrument which was aligned along a known axis (a meridian for example). Then observations of the sun wold allow computation of latitude and with timing signals longitude. Thanks for the insight. I looked on the Observatory's website and there is no mention or picture of the Station, anywhere. I am going to inquire from the Observatory itself about info on what they used this particular one to study.

I am out in Cincinnati visiting my brother. I had done the prerequisite scouting of benchmarks that I would hope to visit. I had been out for a few hours, had excitedly found all the marks for a triangulation point which I will get to logging and a couple of geocaches. I am driving home and I see a sign for the Cincinnati Obsrvatory. I didn't have the paperwork for that partuclar benchmark (JZ3140), but I had remembered the date the mark was set was 1889, because the name made the date seem quite significant. I took some pictures of the observatory building and walked around back to see if maybe I could find the benchmark without any directions from a sheet. What I saw was this: I saw the date was 1881, eight years before the reported benchmark. I got very excited that I had found something special. I hd never found a marker placed before 1912, so this was my first 19th century mark. I get home to look on the computer and find that the mark JZ3140 was reported not found 20 years ago. I could not find any report on the geocaching site concerning this marker. I do not know how to navaigate the governement site too well yet, so that may yield some answers for some of you. This marker was obviously not placed there just for kicks. I've never seen any thing posted on this message board like this since I've been looking in. Was this a very significant find or just a pretty neat marker I came to find?

I've enjoyed following this story through you- very good pictures and reporting.

I have very much enjoyed this thread. Keep those pictures coming!! We may not have the spectacular here in Central Pennsylvania, but we do have simple beauty that I enjoy daily. Here is LZ0298:

I looked up the court decision you stated. This led me to two things: (1) I think this is VERY cool benchmark, and (2) I know why I avoided law school.

OK, Thanks for the updated photo of "the spot." I am glad the monument is still standing, gouge and all. It was a great trip, now I have some new info to go with the old stories. Also, thanks for some of the history on the Mason-Dixon line. I am going to head down to to Maryland this summer and will try to check out some of these marks mentioned. Very cool.

20 years ago, a friend and I made a 600+ mile bicycle trip from NW New York down into eastern PA. At work today, my mind flashed back to a picture that was taken on that trip, since I've been thinking a lot about benchmarks. This picture (which, by the way, when I was scanning, my high school son comes in and says, "Who's that?" and I replied "Your father." and with typical teenager cynicism he shook his head and walked away, shaking his head and saying "That can't be MY father) What is that I am leaning against? It is not a benchmark according to the geocaching website, but obviously it was put there by somebody official to designate the state line. We were coming down NY 26 into PA. As best as I can tell, it is the spot where GCW07Y is. The coordinates, again at my best estimate, are N 41^ 59.942 and W 076^ 00.057. Does this have any significance in the benchmark world, or is it just a neat picture from a simpler (600+ miles, no cell phone or GPSr) time? I do enjoy all you comments, posts, and suggestions. Thanks!

I certainly enjoy stories such as this one. As I'm getting rolling along with this hobby, I am encouraged that there is, as I had expected, more to the process than just "finding the benchmark." Thanks to all you for the posts- I am learning more daily.

Papa Bear, RazorbackFan, and BlackDog Trackers, Thank you for the detailed responses. I think I am finally understanding how all the pieces come together. So, the triangulation station is the "top dog" so to speak, with the reference and azimuth markers helping locate that one? By the way, in this particular case, the azimuth station would have been in clear sight (before they put up the new library a few years back) even though it was so far away, so that makes sense too. All this makes the hunt even more intriguing to me. Thanks for the info. I am looking forward to a really fun summer.

Hello, This is my first post. I've been doing some caching for a couple years now, but have really gotten excited about the hobby since my daughter now likes to go out with me. The benchmarks appeal to both of us, so we're focusing our attention in this area. LZ1902 was given coordinates that were fairly close to our home. We got up there and the coordinates are in the middle of our town's university's baseball field. So, no marker. We read the benchmark history and it suggest the azimuth marker is in another part of town. Sure enough, it is right where the history suggests it is, but the thing that I was confused about is that it's .67 miles from the coordinates. I think I understand the azimuth is a direction aid if there is a problem with other markers (which by the way have been destroyed when the stadium was built). The arrow on the marker DOES point right to the stadium. My two rookie questions are this: why would the coordinates be given so far away from where the marker actually is? how frequently can I expect this to happen? Thanks!