Harry, the "Strange thing" behind me in the mist of my first picture is called a "Trig Point"
Trig points are truncated square concrete pyramids or obelisks tapering towards the top. On the top is a brass plate with three arms and a central depression, this is used to mount and centre a theodolite used to take angular measurements to other neighbouring trig points. A benchmark is usually set on the side, marked with the letters "O S B M" (Ordnance Survey Bench Mark) and the reference number of the trig point. Within and below the visible trig point, there are concealed reference marks whose National Grid References are precisely known. The standard trig point design is credited to Brigadier Martin Hotine CMG CBE (1898–1968), the then head of the Trigonometrical and Levelling Division of the Ordnance Survey.
http://en.wikipedia.org/wiki/Ordnance_Survey The process of placing trig points on top of prominent hills and mountains began in 1935 to assist in the accurate retriangulation of Great Britain. In low-lying or flat areas some trig points may be only a few tens of feet above sea level. When all the trig points were in place, it was possible, in clear weather, to see at least two other trig points from any one trig point. Careful measurements of the angles between the lines-of-sight of the other trig points then allowed the construction of a system of triangles which could then be referenced back to a single baseline to construct a highly accurate measurement system that covered the entire country.
If you want more info on this or anything else to do with the English Countryside please PM me.
Jim
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Billy Fish: He wants to know if we are gods.
Peachy Carnehan: Not gods - Englishmen. The next best thing.
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