Day trip - McKinney Falls

Saturday was booked with a trip to the farmers' market, an adventure in engineering with the "Expose Your Daughter to Engineering" day at UT for Mike and Eleanor, and an afternoon of dessert and non-stop chatter for me and my local girl friends (Karia and Alison).  Sunday we took a short drive (really, it was actually short, even by my standards) to McKinney Falls State Park.  While there, we found an ashy, dark green rock the rangers identified as Bentonite = ancient, compressed, volcanic ash weathered by water.  A new one for us.