Yesterday (September 18) was the birthday of Jean Bernard Léon Foucault (1819–1868), usually known as Léon Foucault amongst his fans. Foucault is best known for his realization that a pendulum allowed to swing in any direction (instead of back and forth in a single plane of motion) on a sufficiently long chain could show the rotation of Earth. Known as a Foucault pendulum today, these devices are a staple of many science museums, including my local museum, the Science Museum of Virginia. I will write a post about Foucault pendulums soon(ish), as a continuation of the general oscillator series.

In honor of his birthday and because I needed another design in my shop, I created a shirt and bumper sticker bearing Foucault’s likeness with the tagline from this blog: “The Pendulum is Mightier Than the Sword.” There are also new bumper stickers and several new T-shirt options, so please go have a look!