"Oh, I have been around enough universities to know all about that." I smiled.

She seemed about to say more, but there was a noise from the direction of the courtyard, where two sturdy men in kitchen aprons approached.

"I had better go," Sophia said, glancing once more with a fearful expression at the corner where the bodies lay. "I am sorry that I will not be able to attend the disputation, Doctor Bruno. I am not permitted, but I should have liked to see you best my father in a debate."

I raised an eyebrow in mock surprise, and she smiled sadly.

"No doubt you think that disloyal of me. Perhaps it is-but my father has such fixed ideas about the world, and its ordained order, and everyone's place in that order, and sometimes I think he believes these things only because he has always believed them and it is less trouble to go on the same way." She bit anxiously at the knuckle of her thumb. "I would just dearly love to see someone shake his certainties, make him ask himself questions. Maybe if he can accept even the possibility that there might be a different way of ordering the universe, he might learn to see that not everything in that universe has to stay as it has always been. That is why I want you to win, Doctor Bruno." With these last words she actually gripped my shirt and gave me a little shake. I nodded, smiling.

"You mean that if he can be convinced that the earth goes around the sun, he might also be persuaded that a daughter could study as well as a son, and that she might be allowed to choose her own husband?"

She blushed, and returned the smile. "Something like that. It seems you are as clever as they say, Doctor Bruno."

"Please, call me Giordano," I added.

She moved her lips silently, then shook her head. "I cannot say it properly, my tongue gets all tangled. I shall just have to call you Bruno. Win the debate for me, Bruno. You shall be my champion in this joust of minds." Then she glanced over my shoulder to the bloodstained grass and her smile quickly faded. "Poor Doctor Mercer. I cannot believe it."

She cast a long look at the mounds of the bodies beneath the trees, her expression unreadable, then turned and ran lightly over the grass toward the college, throwing me a last glance over her shoulder as the burly man who now drew level with me lifted up a capacious sack and said, "Right, matey-where's this dog wants buryin' then?"

Relieved of my last duty of care to poor Roger Mercer by the arrival of the coroner, who came accompanied by the bustling figure of Doctor James Coverdale-the latter hardly bothering to disguise his self-importance in being asked to officiate over the removal of his onetime rival-I left the grove gratefully and hurried through the passageway to the main courtyard. Chapel was over and groups of undergraduates in their billowing gowns stood about in animated discussion, many of them apparently thrilled to be so near to such calamity, even as they pressed hands to their mouths and opened their eyes wide in horror.

It was only just seven o'clock but I felt I had been awake most of the night; I wanted nothing more than to return to my chamber, change my clothes, and try to recoup some of the sleep I lacked before attempting to order my mind in time for the evening's disputation-an event which held little savour for me now. My shirt and breeches were stained with Mercer's blood, a fact Coverdale had taken pleasure in pointing out as I took my leave of him and the coroner. "You'd better find some clean clothes, Doctor Bruno," he had said, with a levity that seemed out of place, "or people will think you the killer!"

I surmised that he was displeased to find me already on the scene and had made an idle joke to puncture any illusion of my usefulness, but as I glanced around the courtyard at the scene of excited consternation, I wondered why he had used the word "killer," even in jest, if it had been given out officially that Mercer's death was a tragic accident. Perhaps I was giving undue weight to thoughtless words; in any event, he was right about my clothes, I thought, looking down at my breeches and holding the fabric out to see the extent of the bloodstains. As I did so, I felt something in the pocket and realised that I was still carrying the keys I had taken from Mercer's body; I must have tucked them away in my own breeches without thinking.

I turned the key ring over in my palm; the smaller key, I guessed, must open the door of Mercer's chamber, since it was a similar size to the key I had been given for my own guest room. I glanced around the courtyard again. The students were beginning to disperse, books in hand, some toward the staircase that led to the library in the north range, others toward the main gate; no one paid me any attention. I looked at Roger's key. Might his room not hold some indication of whom he had expected to meet in the garden, I wondered, and why he had taken so much money? I could take a quick look now, while the students were occupied, and return the keys to the rector later, claiming (truthfully) that I had pocketed them inadvertently.

Roger Mercer had mentioned that he lived in the tower room above the main entrance. I glanced up at the tall perpendicular arches of the first-storey windows, presuming this must be the right place, then with a confident step I passed into the shadow of the first staircase on the west range that appeared to lead up into the tower.

Reaching the first landing, I arrived at a low wooden door bearing a painted sign that read DOCTOR R MERCER, SUBRECTOR. After a fleeting glance to either side, I tried the key in the lock. It turned easily, and I slipped quietly into the room Mercer had left only two hours earlier, never imagining he would not return. For a moment I thought I heard light footsteps quickening away overhead; I froze, my ears straining, but I heard no door open or close and there was no further sound.

I had not anticipated the sight that greeted me as I gently pressed the door shut behind me. The room was in turmoil: books, papers, and maps pulled from shelves and flung in every direction with no care for their contents; garments pulled from chests and strewn across the floor. A thick tapestry rug that must have covered the floor was rucked up and pulled to one side, and marks in the dust suggested that someone had tried to prise a floorboard out of place. Either Roger had left in a great hurry after ransacking his room for some lost object or someone else was also searching for something connected with his death and had got here before me.

The room was long with a high ceiling and stretched the width of the range, the narrow leaded windows overlooking the quadrangle on one side and the street outside the college on the other. On the street side was a wide brick fireplace and opposite it, a large oak desk with delicately carved legs. At the far end, facing the door, were three steps leading up to another doorway, which stood open. Sweat prickled on my palms for an instant as I held my breath and listened for any sound other than the frantic pumping of my own blood as I remembered the footsteps I had heard; perhaps they had not come from the storey above, and someone was still in the room. Stepping as carefully as a cat, I grabbed the nearest thing the study offered to a weapon-an iron poker from the grate-and clutched it in both hands along with my courage as I tensed myself to approach the open door. I stepped through, raising the poker-but the small room, inside the tower itself, contained nothing more than a plain truckle bed, a washstand, and a heavy oak wardrobe with carved panels in the doors.

This little bedchamber had not been spared the searcher's attentions: sheets were roughly torn from the bed, an earthenware jug had been knocked from the washstand and broken in pieces, leaving a damp stain on the rushes that covered the floor. As I drew closer I saw that even the straw mattress had been slashed with a knife, its stuffing spilling out over the bed. In the corner of this square room was a small wooden door set into the wall. I tried the handle but it was firmly locked, though there was a hollow sound when I knocked on the wood; here, I presumed from the echo and the draught that whistled from the cracks, was the staircase to the upper floor of the tower. Gripping the poker, I checked behind the heavy window drapes and under the bed, but found no one. Satisfied that I was alone, I returned to the main room and quietly locked the door behind me so that I could examine the scene in peace.