The thing about having studied math is, you can start out worrying about how to keep the garden watered during dry spells and before long you're asking, “What is the equation of an egg?” The good news is, one is never the first to ask such a question. Hat tip to Japanese mathematician Tadao Itou for an elegant set of parametric equations, which I have adapted here.

It seems an interesting idea to create vessels of ferrocement for waterers and possibly for bird baths. There is much experimentation to be done.