While eating lunch one day a girl noticed that, having shelled their hard-boiled eggs, her parents crumpled up the shells before throwing them away. She asked why they did this.

“If you don't, the witches use them for boats,” they explained. At one time this belief was quite widespread throughout Central Europe.

“Witches need boats, just like anyone else,” she replied, and threw her eggshell, uncrumpled, over her left shoulder. A whirlwind caught the shell and whisked it away.

One day the girl was fishing from an island in the middle of a river. Suddenly, due to a heavy downpour upstream, the water began to rise. Before she knew it, her boat was swept away, and soon the rapids were in danger of covering the entire island.

Just then she heard a voice. An old woman in a coracle was beckoning to her. The girl clambered in, and with some difficulty the old woman brought them back to shore.

The girl climbed out of the coracle and stammered her thanks.

“Witches can be grateful, just like anyone else,” said the old woman, and vanished.

Those of you who compost will know that eggshells last for a good, long time: years, in fact. Well after the tea leaves, potato peels, and onion-skins have turned back to rich, black soil, the eggshells continue to hold their form. It really is best to crush the shells before you put them into the compost heap; this helps them break down faster.

Even so, every now and then I leave a shell or two uncrumpled.

Witches need boats, too.

Just like anyone else.

From folklorist Venetia Newell's magisterial An Egg at Easter (1971), Routledge and Kegan Paul, the single best book on egg-lore and Easter customs.