A visit to the centre of the UK: Dunsop Bridge

Last November I posted about how we found the centre of mass of the UK with a cardboard cut out http://wigtonphysics.blogspot.co.uk/2016/11/centre-of-mass-of-uk.html The method finished like this:

Now I had thought that Haltwhistle was the centre of the UK. But the method given for Dunsop Bridge is the same method I used. See https://en.wikipedia.org/wiki/Centre_points_of_the_United_Kingdom And here's what they say in Dunsop Bridge...