who only by moving can balance

Further fun with blackcurrants: they can be used as a textile dye to get blue. I do not have a recipe for this, alas, and wouldn't be able to get enough of them to try it if I did, but I have run across the reference in multiple places. I also don't know how color- or lightfast it is. Basically I know nothing except that it can be done, and that there's an adorable cartoon about the making of linen in Czech Republic that uses it. You can find it here, and I get very excited about it because it's a very accurate representation of the process, while also being adorable woodland creatures.