Proceedings of the Society of Antiquaries of Scotland, 61, p.297, 1926-7.
Marwick's plan compares
well to modern examples with the exception of the passage. During Marwick's
investigations the NW end of the passage was still filled with earth and debris,
so he had no idea of its
extent or nature of termination.
Marwick's workmen cleared the floor to bedrock and it is interesting to see just
how uneven the this is,
the current gravel floor is level with the bottom of the second vertical
"step" in the rock on the left hand side.
As usual, our sincere
thanks to the Society for allowing use of material from its most excellent
Proceedings.