In the eye of the beholder

If fees were charged for the sight of a rainbow, Cambridge University should receive a commission. Our understanding of the rainbow's mysteries came principally from the faculty of Cambridge, including professors Isaac Newton, Thomas Young, George Airy, Richard Potter, and Lord Rayleigh. Each of these men provided important steps towards our current understanding of the family of bows, which includes the rainbow as its most famous member.

Early references to the rainbow are made in the Bible where it is written that Noah was given the rainbow as a gift and a covenant that the earth would never again be destroyed by water. Homer, in the Iliad, describes Iris as the goddess of the rainbow. Iris was regarded as a messenger, or bridge, between the gods, especially when they intended discord.

The Greeks began the scientific investigation into the rainbow, and claim several important advances. Alexander of Aphrodisias was the first to document the dark strip between the two arcs of the double bow (visible on the cover), and the phenomenon bears his name today as Alexander's phenomenon. Aristotle, about ad 322, …