The Baseline: Color

My first (and so far, only) wife recently gave me a gift: a black scarf that she had crocheted. The scarf wasn't all black — positioned at appropriate positions were colored yarn so that the scarf mimicked the visible emission spectrum of hydrogen! (OK, so both my wife and I are geeks . . . .) She said that she let each row stand for 1 nmr of wavelength so that the scarf represented the 300-nm range that is commonly used to define the approximate limits of visible light. I now look forward to the cold weather so I can wear it. I wondered what inspiration a Balmer-series scarf might provide me for a column for "The Baseline." Once again, my wife gave me a gift — an idea. Why not a column on color?