“It has no justification in experiment exactly; it just represents something that he’s imposing upon the color spectrum by analogy with music.” Of his rainbow experiment Newton ... to half steps in ...

"Why are there so many songs about rainbows?" sings Kermit the Frog in a song (about rainbows) called "Rainbow Connection" from 1979's "The Muppet Movie." And it's not just songs that feature rainbows ...