Northern edge of passage entrance.
This cavity has been left in the cairn casing to reveal the original outer
northern corner of the passage which can be seen on
the very left of the above photo. Childe (4)
believed the stones had been worked " the edges of the stones at the
corner having
been artificially rounded off", unfortunately the southern edge had been
removed in the earlier crude investigations of the cairn,
so this was not available for comparison.