Did I ever tell you that my sister is a fiber artist? When she came back from college for one of her breaks, I remember that she taught me how felt is made from wool fibers. We sat by the bathtub with warm water, a bit of shampoo, and massaged some wool as she explained how the water makes the fibers swell, causing the little ‘hooks’ on each strand to come out, and the shampoo makes it slippery so the fibers can slide over each other, and the little hooks keep grabbing onto other little hooks until that mass of fibers becomes one solid piece of fabric.
That is also what happens when you accidentally throw a wool sweater into the wash because you are doing a load of bathroom rugs and don’t remember throwing the sweater in the pile because deep cleaning a bathroom is hard work and whew! – you can’t remember when you’ve ever been this hot cleaning a bathroom.
Later, you will find that all the little hooks found more little hooks, thereby shrinking your thrift-store sweater.
Fun fact: Every single time I typed ‘sweater’, I spelled it ‘sweather’ first.