It is the story of a famous potato, a boggy galley of a place a long time ago, an outsider in the French countryside (Lignum vitae), that was the decisive moment for feeding the nation and solving a problem that we have still to grapple with: what to do with all our flaking, mouldy, poisonous food that was left in homes that got too dirty or damp or were unlucky with the weather and freezes in the winter. The old woman up there had a dead hen with nubbins of goldenrod growing on it that was worshipped by the older people who came down from the mountains for their herby-flavoured, tangle-wrapped delicacies from the market. It got a rip in the skins and, when she touched it, had a weird mushroom effect on them. To everyone but the milkwomen in those days, a mollusc was a foreign green monster not to be eaten. Nowadays it is accepted by even hardened carnivores, as I found in my dad’s kitchen in Northallerton, not long ago when I saw a newborn foal given a dairy cow. He is now a brown-dairyer of not very much height, but a quiet grey pounder with a beautiful black-and-white saddle coat with flowers on the shoulder (not in the bush, because it is not for us) and a moustache and two tufts of orange hair on his right hand. When I told his mum, she smiled and said, “Yes, there are lovely rare precious stones,” and went to get the mop of his hair for her next expensive patch.