Histarchers,

I have a question that I know at least some of you have had to deal with 
in the past and would like some advice.

I have a private landowner who claims to have some stones with 
astronomical alignments. Some of the stones have makings on them, many 
of which are in the same general direction. My first impression is that 
these were damaged by a plow, but I do not have a great deal of 
experience with this. I have read/heard/seen somewhere that plow marks 
tend to be V-shaped in cross-section and not U-shaped. Is this correct 
or does it depend upon the type of stone?

My main issue however, is that there is a stone wall involved in this 
arrangement. The owner has located all of the deeds back to the 
beginning of records in the area and these stone walls do not fall along 
property lines. It is quite wide, approximately 10 feet. In plan, it is 
in the shape of an L with the long side on the order of 100 feet long 
and the short about half that. The angle is close to 90 degrees. The 
'wall' is disorganized does not appear to have been well-laid, although 
there was one spot that I could see well-laid stones beneath the tumble. 
My question is, what else might this wall be? My first impression is 
that it is merely a rock wall built from the removal of stones for a 
historic field. This is partially corroborated by  reports as late as 
the 1950s that there was a corn field just to the northeast of the long 
wall. However, the L-shape doesn't seem to make sense. If a farmer was 
removing stone from the field, why would he make the L? The short side 
leads off into the woods to a point about half way between the right 
angle and a stream. To the northeast of the wall is the owners lawn and 
to the southwest is woods that leads to the stream- this area is very rocky.

A couple of relevant notes to the puzzle:
An elderly resident indicated that in his lifetime (nearly 100 years) 
there had not been a structure in the location of this wall.
Local residents have collected prehistoric points in this general 
vicinity for many years.

Can anyone think of references that I could look at to see some 
diagrams, photos, etc... of a variety historic stone walls- particularly 
of Eastern PA?

Cheers,
Ben Carter, PhD, RPA