Image Credit: Chris Bickerton
Posted by postman
24th April 2014ce
NB: Unless otherwise stated, this image is protected under the copyright of the original poster and may not be re-used without permission.
There is another similar marking , lower and to the right .
John Barnatt was aware of them awhile ago , they certainly look the part , (with the usual caveats) , from the pics . An early pic would be good .