Some listeners consider Maurice Ravel to be among the very greatest orchestrators in history. The most important aspect of his famous Bolero is that it was written (at least partially) as an exercise in orchestration. He was surprised and disappointed at how the piece became his most famous - it's nowhere near the top of his works, but it is very powerful in both its exploration of rhythm, and the gradual inclusion of the entire orchestra. Listening and following a description (available online) is an excellent way of discovering the "colours" of the orchestra. (It's worth remembering that great artists are also trying to teach us about what they've learned.) Tomorrow, I'll be writing about a piece that is among his greatest.