There are two chart options. One for a lacy look, or a second version that has a spiffy way to tighten the holes for a denser fabric. It might seem intimidating at first (because of the cables, decreases, increases, and twists) but with patience, it’s a good intermediate-beginner project to try new techniques.

The size can be adjusted by using sport or DK weight yarn and a slightly larger needle size. Add repeats of the main chart as needed for hat depth.

The name came about because the pattern (using the version without the lacy holes looks) reminded me of a 2D representation of certain types of fluid-dynamics

YMMV, though. =)