Then I had thought it an illusion, some trick of the wind, or human voices distorted by distance. This time there could be no doubt: it was the lament of the white herons, the same wailing that had come from the piled cages on the deck of the ship at Paola.

I went down the steps and turned in the direction of the sound. I had to follow the shore of the lake, from the farther side, passing the place where the fires had been lit for our supper on the first evening, going beyond this into a part I had not visited before, through trees thinly planted and then over an open space where the grass was tall and wasted with summer. Reflections from the turning mirrors confused my eyes and bedevilled my sense of direction. I was hunting for a sound that came no more, but I persisted, growing more intent as I proceeded. I have sometime thought since that this intentness of purpose came to me through God's mercy.

At last, after much blundering, I came upon a wicker gate and a narrow path that led through trees to a row of bamboo cages, all empty save one and this had the white birds in it, six of them I counted, all that were left, and as I approached they shuffled their wings and set up their wailing, and it was as if I were back in Cosenza, before the meeting with Alicia, when I still had the trust of Yusuf, when Nesrin was filling my thoughts. There was nothing securing the door of the cage but a wooden bar. This I lifted off and held the door open. But the birds would not come for fear of me standing so close. So I left it open wide and began to make my way back towards the palace, feeling as I did so a lightening of the spirit – the first since Muhammed had come.

It was my intention to leave and I was on the way to gather my belongings when I found myself in the courtyard below the room I had occupied on my first visit, which had delighted me so when I had opened the shutters and looked down. The sound of water was everywhere here, flowing from the mouth of the fountain into basins set one below the other and thence in covered channels to the pool in the centre, which was undisturbed for all the little streams that fed into it, and I fell to wondering how this could be so, and marvelling at the art of those who had made it. The respite I had felt since freeing the birds was still with me and it was pleasant there, with the gentle splashing sounds of the water and the coolness it made in the air. The pool seemed deep to my eyes and I bared my arm to test it but the water rose only to the elbow: the appearance of depth came from the blue tiles with which the pool was lined. The immersion of my hand and arm broke the surface, shivered into fragments the pale reflections of the clouds that still accompanied the sun that morning.

There are times after turbulence of emotion when a sort of emptiness comes to the spirit, and it was so now with me. I had been through a great deal since the morning Caspar had come with the summons. I had not slept, but felt no tiredness now, only this vacancy. As I still knelt at the pool, shadows like swift ripples swept across the face of it and when I glanced up I saw the six herons flying together very low, just over my head, saw them wheel and turn westward toward Palermo and the sea. And at once, unbidden, as I followed their flight, there came memories of other shadows, the sunlit afternoon in the Royal Chapel, shafts of light that entered from outside, contending with the light of the lamps, both together making a glory of light on the Magdalen's head and on the raised hand of Christ Pantocrator. Moving shadows everywhere within the space of the chapel, the two workmen high up on the wall with their lamps and their mirrors, they both glanced down towards me at the same moment, but this could not have been because of any sound I had made, I was standing motionless. Nor was there other sound, not at that moment, or I would have heard it. Some swift reflection passing across the mirrors they had on either side? But no movement from the ground could have caused such a reflection, the men were too high above. As high up as the Tree of Knowledge it must have been, or it would not have registered in the mirrors. Perhaps they had seen shadows moving over the wall before them, shadows of some unusual kind, to make them look away from their work… Then I had come upon Gerbert and his German companions, and there had been shadows like those the birds had made on the pool before me, swift shadows moving over the south side of the crossing, passing over the marbles of the floor like birds' wings or ripples on the surface of water.

I tried to concentrate my mind on the recollection of those few moments.

The sunlight had entered from somewhere high up on the south side. I had been standing in the centre of the Sanctuary looking up at the mosaics, those the King would see from his loge opposite, the images to which his destiny was linked: the scene of the Ascension, with Christ borne aloft, prefiguring his own apotheosis as earthly ruler; the standing figure of Virgin and Child, guarding and protecting. Then there had been these flitting shadows. Gerbert and his companions could not have made them, the shaft of light had passed over their heads, it had come from higher up, from a window or aperture on that side. Someone had been moving up there, though very briefly. Someone had passed across the light. Next day had been the Day of Christ's Ascension, a very important day for King Roger and the Norman kingdom he had founded. It was known that he planned to attend the liturgy. His plans had changed, almost at the last moment, the following day he had left for Salerno. Gerbert it was who told me of this change of plan. Gerbert, whom I had seen the day before in the cloister of San Giovanni degli Eremiti in close talk with Atenulf the Lombard. Atenulf, the student of dates and times and symbols, server of the royal power, faithful builder of the King's fame.

All this while I had been crouching at the side of the pool. These thoughts passed over my mind as quickly almost as the shadows over the water that had given rise to them, moments only – my arm was still wet from its immersion in the water. The reflections of the clouds on the surface had formed again, the shallow pool looked deeper than dreams could fathom. I rose to my feet, glanced up to the sky – the clouds looked less real than their reflections. The impulse was renewed in me to leave this place of cheating images, and I turned my back on the pool and began to make my way towards my room.

This wish of hasty retreat was still with me on arriving there and I began immediately to put my few things together in preparation for leaving. As I did so I remembered the hopes with which I had come and I could not prevent thoughts of Alicia returning to my mind, how she had duped me and made a mock of me and the terrible treachery there had been in her heart as she raised her hands in that gesture that had seemed like prayer and slipped the ring from her finger and uttered the words of promise to me. From the beginning it had been there, through all her smiles and glances, this deep well of her cruelty in which she dipped secretly, Satan at her side to hold the ladle, as he had been there with the saw at the side of the traitor Atenulf had spoken of, he who had cut through the chains of the drawbridge in the darkness of night and was soon now to die at Spaventa's hands.

These thoughts brought back the feeling of nausea, which was never far away during these days, and I paused in my movements about the room and stood still, taking deep breaths. And in this moment of enforced stillness it came to me that I had been in a certain way mistaken: the well of ill was deep indeed, deep beyond knowing, but the power of ill was limited, and this was true also of Alboino and Bernard. In my misery I had seen conspiracy everywhere, but it seemed certain to me now that neither the one nor the other had played any part in sending me to Potenza – the time they disposed of had been too short.