
Are any 1950??s subdivision plats selfconsistent?
I have at various times tried to check three local subdivision plats from the 1950??s and have yet to find one that I can get to fit with themselves at a reasonable accuracy (never mind what??s on the ground). Is this the ??normal? case?
I??ve been fighting one and am so frustrated I need to vent. I pulled the plat from the online records for a friend and computed chords for his frontage curve so he could measure to look for monuments, in preparation for rebuilding a stone wall. It turns out there are monuments, but his frontage and the adjacent ones all measure a foot or three in excess of the plat dimensions (7.7 ft excess in 178 or 4.3%), which has us scratching our heads. If there are discrepancies, I??m not surprised they are on a curve.
So to start I computed the exterior of the 20lot subdivision. Angles given to 1 minute sum just 1 minute off, but the closure is over 2 ft. Least squares holding the given angles tight wants one distance to increase by 2.0 ft northsouth (43.57 to 45.57) and another to shrink from 106.95 to maybe 106.095 NWSE. Those changes give excellent closure of the exterior, but I can??t get the lots to fit. There is 2 or 3 ft floating around when you try to fit all the lots in, either with or without changes to the exterior. One curve checks out with its parameters pretty well. Others don??t fit within many tenths to a foot. I??ve tried looking for likely misreadings of the numbers on an imperfect photo of the plat, tried holding or freeing the delta angles and/or radii, holding one area tight to see what others fit, etc. The city GIS shows the same numbers I read from the plat, but their distances don’t scale out to match the labels. Nothing gels. There aren??t enough identifiable points (fence lines, etc.) on Google Earth to use occupation to look for misreadings at the 1 or 2 ft level. I??m pretty much at an impasse.
On another 1950??s plat I once looked at, the exterior boundary angles given failed to close by 42 minutes. Playing with holding various interior lines failed to identify a simple copy error (or two) that would allow things to fit well.
There is another 1958 plat with an exterior that doesn??t close by about 10 feet. I think the bearing of the south line was computed from the center of the street, forgetting that the street being extended wasn??t centered on the quartersection line, so that one is easy, but I??m not sure how much that affected the interior. It has some lots with their rear corners offset from each other, and the distances on each side of the common line add up 0.8 ft different. It has right angles indicated where a lot dimension would have to change 0.5 ft to match. Some of the curve data given is selfconsistent with arc formulas, others almost match chord formulas, and some just don??t make sense. Trying to fit anything around the curves doesn??t seem to work with at least a foot either missing here or left over there.
So my question: did I just stumble across the bad ones, don??t I have the right technique for finding scrivener errors and misreadings, is it an indication of poor local practice at the time, or is that just the way things were everywhere in the 1950??s?
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