Peter Hayes wrote:

But isn't the Coriolis effect responsible for uneven wear on north/south
railway lines, with the more easterly rail wearing more, since the
locomotive is being pushed in that direction. Or is that anothe urban
myth?

Who told you that one?

If you had a logical reason for believing it you would have considered
the other parameters such as the fact no rail lines are ever perfectly
straight and that most engines in locomotives will be more likely
culprits, if there is any possible reason to believe anything about it.

As regards a bathtub and all that stuff, the container is moving about
the earth's axis at the same velocity as the water in it. What else
seems to evade everyone when this subject arises (perennially) is that
the water on the top of the resevoir has more potential energy than the
stuff below it and this energy is not directly used up in falling
through the plug hole.

Large votices have lesser ones and they still less inside them and
smaller ones have smaller ones all making up the wide 'un.