"Bluebirds over the Mountain"

I listened to the Friends/20/20 two-albums-re-issued-on-one-CD this morning because I'm not as familiar with either as I'd like to be (I think I've listened to this re-issue only a few times).  "Bluebirds over the Mountain" got stuck in my head, and because of that, I realized something about the title line.  The melody is such that "bluebirds" (sung to C# notes) really are "over the mountain" as far as musical pitch ("the mountain" is sung to the phrase B B A A).  Likewise, "seagulls" (sung to D notes) are "over the sea" ("the sea" is sung to the phrase C# C# B A B).