A winning analytical technique in Physics is breaking angled vectors down into horizontal and vertical components. Finding the truly horizontal can be important. I took this picture at Shap Church last week with some vague memory of what it was from childhood. Mrs B did the research after we had discussed the trig point network and found out that it is a benchmark. In surveying, the height of each horizontal line is worked out by triangulation from other marks. Church towers are useful because they are very prominent landmarks. We found info on http://www.bench-marks.org.uk/
