Air on the G string.

[Enrique]

I was just listening to the second movement in Bach's orchestral suite No. 3 in D major, BWV 1068, also known by the name of a famous arrangement, Air on the G string. No doubt, when Bach wanted, he could be the supreme melodist. I think symmetry is the keyword for this piece. I wonder, does the scheme in the bass, almost in the form of a basso ostinato, correspond to some particular musical form?

[Peter]

I'm not sure what you mean really - I imagine from memory and without score that the piece as a whole is in binary form. The bass begins as a descending scale separated by octave leaps.

[Enrique]

The descending scale is always there! The form may be binary, but the bass strings seem not to know about that. This piece of music could be taken as the basis for a generalized definition of passacaglia, given that a name for it does not exist.