The colors of the outer bow, Spectral 12, appear the same as the colors in Spectral 11,- with the exception that each color band is half the width of its corresponding band in Spectral 11. This suggests that the cones in my eyes can respond to the harmonics of the wavelengths they are tuned to,- just as a Radio antenna can. It clearly shows that all the harmonics of a color actively present the same visual sensation to my brain.

The gap could mean the existance of a color with extremely low chromacity and luminosity, or the extension of that gap could be due to the geometry of the atmospheric prisms that dispersed sunlight into the double rainbow. A differnt prism may shorten the gap to the expected size. The one thing that is clear so far, is that I need to look at a lot of things to complete this enquiry and the testing of my hypothesis.  Of course I could look it up on the Internet, or find it in a book, but that would make me a spectator of Science rather than a participant in the Sciences.