Entry 04 · Trilogy 2 · Light through water
The Rainbow: 42° Every Time
You have seen thousands of them. You have never once had to ask why they appear. The primary bow sits near forty-two degrees.
A rainbow is not a place. It is a direction: Descartes’ minimum-deviation angle for a spherical water drop, about 42° for red light.
Move, and the bow moves. It is a geometry you can stand inside without ever arriving. The Book loves this because it is true on every wet afternoon, with or without a chronicle.