The merchant opened a wooden box. ‘I have kept them dry and sweet, and hidden from the light as Mr Tradescant advised me.’

He held out a handful of woody twisted roots, brown, with a dusty earth still clinging to them. The earl took them gingerly and handed them to John.

‘They are the roots of flowers of exceeding fineness,’ the merchant said rapidly, his eyes on Cecil’s impartial face. ‘Roots of course, Your Grace, never look well. But in the hands of your gardener you could bring these on to flower in great profusion …’

‘And what is the flower like?’ John asked.

‘Like a geranium,’ the merchant said. ‘And the leaves are sweet, like geranium leaves. But much finer, a quite extraordinary blossom.’

Cecil raised an eyebrow at John. John made a small shrug of his shoulders. They looked like the roots of a geranium but with neither leaf nor flower no-one could tell. They would have to be bought on trust. ‘Anything else?’ Cecil asked.

‘These.’ The merchant pulled a little hessian purse from the bottom of the box and opened it. Inside were fat green globes as large as a bantam’s egg with hard little spines all over.

‘A new chestnut,’ the merchant promised. Gently he prised open one of the shells, and spilled, into John’s cupped palm, a bold round handsome nut, dappled like a brown roan horse in light and dark brown, with a paler grey and brown circle at the top. John caressed the moist inside casing of the shell, turned the nut in the light to see the sheen on it. Bigger than a walnut, shinier than mahogany, it was a delightful nut, a great jewel of a nut, a brown warm pearl.

‘Where did you get these?’ John could not keep the quiver of excitement from his voice.

‘Turkey,’ the merchant said. ‘And I saw the tree that gave this fruit.’

‘Can you eat them?’ Cecil asked.

The man hesitated for that single half-moment which reveals a lie. ‘Surely,’ he said. ‘They are chestnuts, after all. And they are a powerful medicine. The man that sold them to me says they use them for curing broken-winded horses. They mend the lungs of horses, perhaps of men too.’

‘Is the leaf the same as our chestnut?’ John asked.

‘Bigger,’ the merchant replied. ‘And spreading. And the trees are massive round trees, better-shaped than ours, like a great ball on a stick. And when they are in flower they are covered all over with huge white cones of flowers, as big as both your hands. White blossoms and the tongues of the flowers are speckled with pink.’ He thought for a moment. The price would depend on his description. ‘Like apple blossom,’ he said at once. ‘White and pink together like apple blossom, but in a great shape like a cone.’

John fought to keep the excitement from his voice. ‘Great trees? What height?’