These two bronze sculptures date from the beginning of the Roman imperial era, somewhere in the first century AD. They show toddler girls trying to catch a partridge. Or possibly a pigeon?

They sold at auction in New York for millions, through private sellers, before investigators established that they had been stolen from an archaeological site in Spain. They have since been repatriated to the National Archaeological Museum in Madrid.

What strikes me is how Baroque they look. The movement and the drama, the little arms reaching forward. The bronze work is extraordinary, both toddlers have inlaid pearl eyes, although only one remains intact. The bird is rendered with a real understanding of how birds hold themselves and shift their weight. Someone who had spent time watching birds and children play, made this.

We are used to what survives the classical age being largely imperial busts, heroic figures, titanic architecture. It is much rarer to find something playful, something domestic, something that probably sat in a villa garden and made the owner smile on the way to dinner. An everyday moment, caught.

The cast bronze lets us see through the eyes of an artist who died over two thousand years ago, at a moment perhaps imagined, perhaps witnessed, and held there ever since.

It is exactly what Keats was reaching for in his Ode on a Grecian Urn. Beauty as a kind of arrest. Time stopped mid grasp, the bird never quite caught.