> Are you asking why does a vortex form at all? No.
> Are you assuming that the > drain is "rifled" in some sense and that a vortex wouldn't form without the > rifling. No, that hadn't occurred to me, and I don't think (having done my share of household-level plumbing) that drains are rifled in any sense. Like Isaac Newton (not Abraham Lincoln's secretary of agriculture, who should be better known than he is for having written "there is no logic so irresistible as the logic of statistics; some other guy of the same name), I am not feigning (or framing) hypotheses on these matters, at the moment anyway. I was mainly pointing out that your reported observation, about the (great) slowness to drain of a vortex-infested sinkful of water, *is* an observation *about a sink full of water*, not (just) about the visible part of the water, or even (just) about the water and the visible surfaces of the sink. At least part of the water that is already out of sight (at any particular time during the process of draining the sink) is most definitely mechanically involved with whatever is happening, as is at least part of the sink (the top bits of the drainpipe) that is out of sight during the whole experiment, because that water (rather, the outer layers thereof) is touching that part of the sink. Like the man said, no system is an island, entire of itself; every system is a subsystem of the Universe, a part of the main ... And therefore never send to know for whom entropy increases; it increases for thee. --Not that I'm framing any hypotheses about order or disorder, mind you. ============================================================ FRIAM Applied Complexity Group listserv Meets Fridays 9a-11:30 at cafe at St. John's College lectures, archives, unsubscribe, maps at http://www.friam.org
