A call to the well digger last night informed me that he had punched through the limestone and was back into creek gravel. His tone of voice sounded worried. Since I don't know any better, I haven't started fretting.
Down to 40 feet. More will happen today. A dry hole is an expensive possibility.
I find out, with a little research into spudding with cable tool drills, that this is a pretty archaic method. Slow but at least he showed up after a year.