BE-DE: Smallest Vennbahn enclave

I have uploaded to the files area an Excel spreadsheet with the 
measurement data for the smallest Vennbahn enclave.
Basically it is a series of measurements showing the turning points 
of the real boundary.
These are given as deviations of the boundary from an imaginary 
straight line joining adjacent boundary pillars. Measuring from one 
stone to the next, the perpendicular deviation from this line is 
given (y-coordinate) at each turning point, along with the 
corresponding distance along the imaginary line (x.coordinate).
For each of the 4 sides of the enclave, this data is graphed to show 
how the boundary wiggles between pillars.

I have also calculated:
the length of the imaginary lines between pillars,
the actual boundary length between pillars
the % difference between these two, and
the interior angles between these imaginary lines.


Note however that there are some inconsistencies in the data, which 
has been taken from the official boundary atlas, published in 1922 by 
the Boundary Commission itself.

There appear to be some contradictions between figures: a straight 
line distance between two pillars, #756 & #757, for example, is given 
as both 155.51m and 155.45m in the Atlas. I have used the latter 
figure in my calculations. It does not make a significant difference 
to the results, either lengths or angles, but it is annoying, and I 
cannot understand how either figure can relate to a different 
measurement. This seems to occur in several places in the atlas two 
figures being given for what seems to be the same measurement. I 
cannot explain it.

I also have a small right-angled triangle that connects the midpoint 
of the boundary between stones 756 & 759 to a German survey control 
point, as having a hypotenuse of either 19.32m (in the Atlas) or 
19.2563m (from my own calculation involving the atlas figures for the 
other two sides). Again I cannot see how the Atlas figure can apply 
to any other length depicted in the atlas). I have used my own figure 
in the ensuing calculations.

Thirdly, one angle given as 133deg 54.3min is clearly wrong in the 
atlas. the correct figure should be 226deg 6.3min. But as this is 
almost exactly the complementary angle, I can see how the mistake 
might have been made in this case. I have used the corrected figure.

Let me know if this file is useful/interesting.

I could add in calculations for the area of the enclave, but can't be 
bothered right now!



Brendan



 
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