Radiómetro de Crookes Mini

I’m honestly impressed by how well the tiny vanes spin even in indirect indoor light—the effect is mesmerizing. The glass bulb is small enough to slip into a pocket, so I’ve been taking it to the café to watch it catch the sun.

I was skeptical a mini would work this well, but even a desk lamp gets the four little vanes turning smoothly. It’s small enough to fit in my pocket, yet the contrast between the black and white panels is surprisingly clear in direct sun.

The blades spin almost instantly when I angle it toward the window, and it’s tiny enough to sit on a crowded bookshelf without taking over. I’ve caught myself just staring at it during work breaks, it’s oddly calming. Definitely the best little conversation starter I’ve picked up in a while.