This is the John Michell Memorial Lecture for 2015. Megalithomania is a long-standing annual event at Glastonbury in which people present fringe research some of which, in kinder times, would be called cutting-edge. My powerpoint slides (available at academia.org) have been integrated by Hugh Newman et al to create a very useful audio-visual of my research reported in Sacred Number and the Lords of Time.
My thanks to Hugh Newman for inviting me to speak and
to Christine Rhone for making it the John Michell lecture for that year.