Hi Moth, Jane, Goffick and Pilgrim.
Just in case you are interested, I was in America last summer working with Rob Roy, a real stone circle enthusiast, Pagan and general nice guy.

I helped with his successful experiment, placing a lintel stone, and he and his crew helped me erect a standing stone utilising the sloping side of a stone hole as found at Stonehenge. (The experiment that we didn't have time to do in 2005).

While I was there I also worked with another man who impressed me greatly, Vincent R Lee, who has done a great deal of work trying to solve the problem of how the Incas were able to move heavy stones in confind spaces. His solution involves the use of levers, but in a way that had never occurred to me.

Best regards Gordon