Those things are neat. I always wondered why they were wrapped around vertical pipes rather than horizontal, because intuitively it seems like horizontal would

Those things are neat. I always wondered why they were wrapped around vertical pipes rather than horizontal, because intuitively it seems like horizontal would be better, but that's not the case. I looked it up and it's because falling water in a vertical pipe will cling to the pipe wall, while in a horizontal pipe it will just sit in the bottom. It's obvious in hindsight, but I've never thought about the physics of water in a vertical drain pipe.