Julian Cope presents Head Heritage

This picture of the Hags Chair features a possible representation of the plough,
http://www.themodernantiquarian.com/post/44244/images/cairn_t.html
however it's also a good illustration of how the evidence can be 'bent' to fit the theory. If you look at the illustration in Fergusson's book (p.215) the lines that join the cups into the shape just don't exist. In other words the picture has been doctored.