Mary Mary quite contrary
How does your garden grow?
With silver bells and cockle shells
And pretty maids all in a row.
But what the cockles mean in this nursery rhyme - if anything - is anyone's guess. If the rhyme is about being a Roman Catholic, then they're perhaps a symbol of pilgrimage; if it's about Mary Queen of Scots, then they might be a snide joke about her husband's not being faithful; if it's about the English queen Mary Tudor then they might even be a sort of instrument of torture - which is a horrible use of a lovely word.
Anyway, we're lucky enough to have another cockle song to sing, too, if we feel like it: there's an Irish one about Molly Malone, who:
wheeled her wheelbarrow
Through streets broad and narrow
Crying cockles and mussles alive alive-oh.
Now, this song seems to be about - well, a young lady who sold shellfish.
And thank heavens for that.
Now, cockles: they're not stupid, you know. They spend their lives lying about on sheltered sandy beaches, which surely proves it.
They have a sucking-in water hole, a blowing-out water hole, and a foot hole (they can jump about if they want to); and as the sea water in which they live is a sort of thin soup of their food, plankton, they never have to go shopping.
In England our ancient (1215) Bill of Rights, Magna Carta, gives everyone the right to gather eight pounds of cockles without a licence, hurray!
How nice to think of all those ancient barons worrying about the common people's need for shellfish. Why, it's enough to warm the cockles of your heart, that is.
What? Oh. Well, cockles are heart-shaped, which is possibly something to do with it.
Word To Sing Today: cockle. The word for the shellfish sort of cockle comes from the Old French word coquille, which means shell, and before that from the Greek word konkhulion, which means little mussel.
As for cockles of the heart, well the scientific name for a cockle begins Cardium, which is the Latin for heart. Little heart is coculum.
Or perhaps it's come from the scientific name for part of the heart, the ventricles, which is cochlea cardis.