Last bit. There was a backstone but not the fallen stone. It was where a backstone should be and the 'fallen' stone leant quite high up against the inner face of the front closure stone and diagonally down and behind the base of the real backstone where it lodged to stop it sliding down. If you observe outside of the quoit to the south side you will observe the 'window' or entrance to the upper chamber with the same slope to it's 'cill' as the diagonal division. Nobody ever mentions that window, well they have now :-)That's all I'm saying. I keep saying to buy the book, jeepers it's cheap enough, but would like to thank all those that already ordered it although only a couple are from here. I'm very very pleased with the response for a book that only came out last thursday and over Easter.