Where Am I?
For the better part of nine years now I've not known exactly where most of the boundaries of my property here on the mountains might be found. I only knew the location of four surveying markers along the road front and the far most back corner which happens to also be a corner of the Blue Ridge Parkway marked by a prominent monument. Armed with my handy-dandy $150 hiking GPS receiver, I set out to find the others.
Now the signal from the global positioning satellites has had noise added for non-military uses and with my instrument I cannot know exactly where in the world I am with an accuracy any better than about 20 feet. But, if I use my instrument to mark a "waypoint" (say, a known property corner), then I can use that same instrument to measure the distance from that "waypoint" with an inaccuracy of only a few inches. And, just like the survey map, the GPS measures the plan view dimensions, eliminating the lengthening errors introduced by hilly terrain.
Further, if I know two waypoints on a line, my GPS unit can tell me how far I am "off course" (away from the line at a right angle). Fortunately, the parkway line has two monuments I could use and a second boundry line shares one of the parkway monuments and a second property corner a known distance from my corner. As such, finding my missing corners was a matter of getting "on course" by moving to the property line and walking down it until I was the distance indicated on the survey map from a known "waypoint".
The first corner I found on the parkway line, the GPS missed "off course" by about a foot and was dead on the distance from the known waypoint. The remainder were even closer. All, this with a $150 instrument deep in the woods with an imperfect view of the sky.
Now when I say finding these markers is like finding a needle in a haystack, I must tell you these markers are half-inch rods, installed 20 years ago, sticking about an inch out of the ground and covered with leaves, twigs and dead branches. It was amazing to reach down, remove the debris with the fingers of both hand and expose the markers surrounded by nothing but acres and acres of trees and rhododendron bushes.
Of course, a hummingbird could have found the corners without the help of global positioniong satellites!
Now the signal from the global positioning satellites has had noise added for non-military uses and with my instrument I cannot know exactly where in the world I am with an accuracy any better than about 20 feet. But, if I use my instrument to mark a "waypoint" (say, a known property corner), then I can use that same instrument to measure the distance from that "waypoint" with an inaccuracy of only a few inches. And, just like the survey map, the GPS measures the plan view dimensions, eliminating the lengthening errors introduced by hilly terrain.
Further, if I know two waypoints on a line, my GPS unit can tell me how far I am "off course" (away from the line at a right angle). Fortunately, the parkway line has two monuments I could use and a second boundry line shares one of the parkway monuments and a second property corner a known distance from my corner. As such, finding my missing corners was a matter of getting "on course" by moving to the property line and walking down it until I was the distance indicated on the survey map from a known "waypoint".
The first corner I found on the parkway line, the GPS missed "off course" by about a foot and was dead on the distance from the known waypoint. The remainder were even closer. All, this with a $150 instrument deep in the woods with an imperfect view of the sky.
Now when I say finding these markers is like finding a needle in a haystack, I must tell you these markers are half-inch rods, installed 20 years ago, sticking about an inch out of the ground and covered with leaves, twigs and dead branches. It was amazing to reach down, remove the debris with the fingers of both hand and expose the markers surrounded by nothing but acres and acres of trees and rhododendron bushes.
Of course, a hummingbird could have found the corners without the help of global positioniong satellites!
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