Wind Against Current

By Johna Till Johnson and Vladimir Brezina

It was bound to happen.

Take a scientist and an engineer, add a kit designed for children, and you’ll end up with a science project.

A few days ago (on the first day of spring, to be exact), we decided to color Easter eggs. We’re not sure whose idea it was (each of us says it originated with the other), but regardless: There we were with 14 hard-boiled eggs and the same PAAS egg-dyeing kit that Johna remembered from childhood. (In Czechoslovakia, too, a country nominally communist but where Easter traditions were hard to uproot, Vlad had something very similar.)

We set to work. The dye tablets fizzed in the vinegar, the appropriate amount of water was added, and the first six eggs were happily soaking in their colors. And then one of us noticed something:

“Hey, what are those lines?” As the dye deepened, several of the eggs were showing white lines, two per egg, circumscribing the eggs and trisecting them neatly. Why was this happening?

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