Berwick Bassett, nr Avebury, Wiltshire.  
Reported 10th June.

The "Wankel" formation in barley three miles North of Avebury at
Berwick Bassett,.

Now we are getting somewhere, this 150 (?) footer is really
beautiful! However I am pretty sure it was made by Earthlings,
as the center is a bit lopsided. To keep everybody happy I have
combined two shots, the close up shows exactly how it is, while
in the wide angle shot I have used PhotoShop to reconstruct it
the way I suspect the artists intended.

The formation is composed of nested bulging triangles that are
scaled and rotated. The shape is like the rotor of a Wankel
engine. It is formed when a Vesica Pisces is cropped with a
third circle. Several years ago Michael Glickman brought to our
attention the fact that, other than a circle, this shape is the
only two-dimensional figure which rolls smoothly. If you roll
it along a flat surface with a board on top, the board would
ride perfectly level -- hard to believe, but true!

The Wankel shape can be found hidden in the geometry of the
recent formation near Barbury Castle. More dramatically, it is
a key element in last year's "Hopi Moiré." I took a lot of
flack for doing extensive PhotoShop reconstruction on that one!