A Hidden Trig

Image: © Ian Dodds Taken: 16 Sep 2022

Having looked at a number of other pictures of this trig point taken over the years, it currently seems to be even more inside the hedge than ever before, although there is at least now no need to remove earth by hand in order to reveal the flush bracket. It is officially named 'Cousland' after the nearby and now unoccupied farm on the other side of the main road, and can only be seen by going to the other side of the hedge from the grassy tack that now leads to nowhere. The flush bracket is the metal identification plate that is almost always attached towards the bottom of one of the sides of the trig pillar. The heights of trig points can be found online down to the millimetre. Cousland is listed as being 158.230 metres. This height, though, is the height above sea level at the top of the arrowhead on the flush bracket, and it is not clear from basic research how much higher this mark is from actual ground level, or whether this height difference is the same on all pillars. Because most people encounter trig pillars at the top of hills, a mistaken belief - which I too held for years - is that the three metal hoops attached to the top were put there in order that the trig pillar could be lowered down from a helicopter. The first trig pillar was erected in 1936, and the first helicopter appeared in 1939; all were actually built on site with the materials lugged there by hand, and the hoops are just there to secure the measuring apparatus in place on top of the pillar in bad weather.

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