Wall corner piles and wall "bulges"

Walking up the northwestern side of North Manoosnoc, saw discarded rocks piled up in a tidy right triangle in the corner of a wall - a not uncommon feature:Then something a little less common, an isosceles triangle built along a wall. This looks a bit like a bulge in the wall but actually there is an older, lower wall coming in perpendicular to the main one (on the left side of the picture) and there is rock piled up in each of the two corners formed between the lower wall and the main wall.

After that, it was pretty much rock piles and ceremonial features, giving me pause in overly hasty dismissal of these wall features.