Here below is a detail from the 1934 photo; the circle on the right is the house and wall pictured in the above three photos; the left is my Uncle Bob's house lot...
Above: Uncle Bob's house (and his rebuilt stone walls).
Below: a little bit of the old zigzag remains in the foreground, in the distance the remnants of what my uncle recalls as a "stone wall," but may be a sort of mound.
Below: possibly a bear effigy
Close up of possible drill mark in large boulder above: