Every autumn, conkers fall in their thousands.

We pick them up, turn them over in our hands, perhaps put one in a pocket, then leave the rest beneath the trees.

Horse chestnuts contain saponins. Chop the conkers, simmer them in water, and these compounds pass into the liquid. The water becomes cloudy and may begin to foam.

Once cooled and strained, the liquid can be used for washing clothes.

Gather some freshly fallen conkers and take them home. Cut them into pieces, add them to a saucepan of water and simmer gently for fifteen to twenty minutes.

Watch what happens as they cook.

Before using the strained liquid, put a little in a jar and give it a shake.

See what the conker has been holding all this time.