Anyone know what this is? They are embedded in the sidewalks around the city
Anyone know what this is? They are embedded in the sidewalks around the city
Any ideas?
39 comments
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That is a surveyor's mark called an Above Ground Marker. It is used as a point of reference when they survey they land.
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Its called a benchmark, used by surveyors as a known point from which to take readings. We had a benchmark on the edge of of our property in the town where In grew up. It was a square, white marble column, like a truncated obelisk with the point cut off to make a 4" square flat top, buried at the roadside and standing a couple inches proud of the grass. It had a cross with a dot in the middle, and a geodetic ID number engraved on the top.
Nailed it with the lawnmower once or twice. That'd really put the Fear in you.
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My grandma has a little concrete thing like that that marks where her property ends (or where 1 part of it ends, legally it's 2 rectangles sharing a side). Once after not mowing for like a month and a half I forgot it was there and totally ruined the freshly replaced blades 🥲
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Control point for ley lines. Keeps the magic channeled to prevent chaos from breaking out.
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Yeah, this. You can step on one, and it's fine. Just don't step on two and complete the circuit, it's like boofing the third rail.
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I left reddit partially because every fuckdamn top comment in an info request thread was a joke.
You guys seriously going to make that the norm here too?
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A marker point for geodetic marking. Also known as triangulation station or trigonometrical point, it's fixed to the ground with its known coordinates.
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Cool! Interesting, I thought True North meant that they somehow pointed north given another reference. Thanks for the info.
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They hold the sidewalk down, don't pick it up or the whole block could blow away.
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Yep, these are the measures that keep the underworld locked for the rich and I am tired of pretending it's not.
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Survey marker, used by surveyors to calibrate equipment. So I've been told, anyway.
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Canada’s look different. They have a reference number
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This is a survey monument vs the original post being a control point. Survey monuments are established on a larger scale.
When you need to reference a known elevation or XY coordinate, there is a network of survey monuments with known coordinates, usually installed and documented by governments. You reference a known location’s elevation and north x west coordinates and then use instrumentation to determine angle changes to transfer the known elevation to a series of other locations.
When you section off property or build things, like roads or buildings, you use this network of points and triangulate paths off of them to the job site by calculating angles and distances. Since you have to maintain line of sight while traversing the distance, you add points you can use to pivot on and travel great distances. These points are called ‘control points’ or ‘benchmarks’.
The main post pic is a control point. Your picture is a survey monument.
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You see those in the US too. I think the one in original photo is for temporary use. I.e. embed it for your project and leave when done.
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That would make sense given the lack of refrence numbers.
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Just more proof they're* holding us down.
*Blessed autocorrect
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What was the original text?
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< We reach/tether >
< through Control Points >
< into the Bureau/House >
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The Rule of Three applies, of course.
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What city is this in? Because I've never noticed one in nyc
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Seattle
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once you start to notice them, you'll never stop seeing them everywhere.
this one is a magnetic nail, so it can be found more easily with a metal detector, which is pretty handy when there's a foot or two of snow on the ground.
you'll also see crosses, squares, and triangles carved out in stone, as well as the super common drill holes in concrete, which are typically only for temporary points.
I've found 100+ year old control points drilled into old stone walls, and they can still check within like ¼" of the new maps.
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Mind control relay. You can try to remove it but are mentally incapable unless you have a tinfoil hat.
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Shotgun shells buried in the concrete. Don't stomp on them too hard!
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or do, and have some fun.
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39 comments