At once I knew I should have said nothing. If I said yes, that I had seen the laws of the Jews and the prayers, then I would have identified myself and my father beyond doubt as Jews and practising Jews at that. I thought of my mother telling me that my vanity would get me into trouble. I had always thought that she meant my love of fine clothes and ribbons for my hair. Now, dressed as a boy in a fool’s livery I had committed the sin of vanity, I had been prideful of my schooling and the punishment could be extreme.

‘Mr Dee . . .’ I whispered, aghast.

He smiled at me. ‘I guessed you had fled Spain as soon as I saw you,’ he said gently. ‘I guessed you were Conversos. But it was not for me to say. And it is not in Lord Robert’s nature to persecute someone for the faith of their fathers, especially a faith which they have surrendered. You go to church, don’t you? And observe feast days? You believe in Jesus Christ and his mercy?’

‘Oh yes, my lord. Without fail.’ There was no point in telling him that there was no more devout Christian than a Jew trying to be invisible.

Mr Dee paused. ‘As for me, I pray for a time when we are beyond such divisions, beyond them to the truth itself. Some men think that there is neither God nor Allah nor Elohim . . .’

At his speaking the sacred name of the only God I gave a little gasp of surprise. ‘Mr Dee? Are you one of the Chosen People?’

He shook his head. ‘I believe there is a creator, a great creator of the world, but I do not know his name. I know the names that he is given by man. Why should I prefer one name to another? What I want to know is His Holy Nature, what I want is the help of his angels, what I want to do is to further his work, to make gold from base, to make Holy from Vulgar.’ He broke off. ‘Does any of this mean anything to you?’

I kept my face blank. In my father’s library in Spain there had been books that told of the secrets of the making of the world, and there had been the scholar who had come to read them, and the Jesuit who wanted to know the secrets beyond those of his order.

‘Alchemy?’ I asked, my voice very low.

He nodded. ‘The creator has given us a world full of mysteries,’ he said. ‘But I believe that they will be known to us one day. Now we understand a little, and the church of the Pope, and the church of the king, and the laws of the land all say that we should not question. But I don’t believe that it is the law of God that we should not question. I think that he has made this world as a great and glorious mechanical garden, one that works to its own laws and grows to its own laws and that we will one day come to understand it. Alchemy—the art of change—is how we shall come to understand it, and when we know how things are made, we can make them ourselves, we will have the knowledge of God, we ourselves will be transubstantiated, we shall be angels . . .’