Birthday Boy

I know it is a bit irreverent to refer to a musical genius as a birthday boy, but it's the first full day of spring and time for a bit of irreverence. Today is full of bird song. It doesn't need a score. But if you're looking for one, try this piece by Bach, born 325 years ago today.
http://www.youtube.com/watch?v=QbTGUurbGTk&feature=PlayList&p=79FD3A8533D012D3&playnext=1&playnext_from=PL&index=23