This was a four part series, the first part "down from the mountain" is actually parts 19 to 26 on Scott's link above. This looks at old-time, bluegrass, Jimmy Rodgers and Carter Family.
Thanks to Scott for posting the link as I've been looking for part one of this series for years!
Incidentally, I love Hank Williams probably because of his band and the bluesiness. Different strokes for different folks....