I stopped, a piece of meat halfway to my mouth, and stared at him, slack-jawed.

"What?" Sidney stopped chewing.

"Foxe's Book of Martyrs. The rector of Lincoln has a great interest in him-he has been preaching sermons in chapel with Foxe as his text."

Sidney frowned.

"You think someone wanted to get rid of this Mercer and took inspiration from Foxe for his method?" His expression betrayed his scepticism.

"It does seem far-fetched. Perhaps I am reading too much into it." I passed my hands over my face. "You are right-it was probably just a bad debt or trouble over a whore. No wonder the rector wants it covered up while a royal visitation is in town."

Sidney was silent for a moment. Then he banged a palm down on the table.

"No, Bruno-I think you are right to be suspicious. The dog was loosed into the garden by someone who had a key, which suggests one of the Fellows or someone else with access to the college keys. And at least two people wanted something from his room, but not money. Perhaps something that might be dangerous to them. And if everyone in the college has recently heard stories of the saints' gruesome deaths from Foxe's book, thanks to the rector, perhaps in some way it was staged as a deliberate copy. The question is, why? Did you find nothing in his room?"

"Only this. Take a look," I said, extracting the slim almanac. "What do you notice first?"

Sidney turned a couple of pages, then looked up at me, his face serious.

"Gregorian calendar. Was our man a secret papist after all, like his friend Allen?"

"I wondered. I heard him cry out to Mary before he died."

"I'd cry to Mary if a dog that size was snapping at my arse," said Sidney bluntly, turning the book over in his hands. "That signifies nothing. But this calendar-you would only need this if you were corresponding with someone in the Catholic countries. Especially if you needed to coordinate movements. Edmund Allen went to Rheims, did he not? Wasn't he related to William Allen, who founded the English College there?"

"A cousin, they said. Mercer could still have been in touch with him, you mean?"

Sidney glanced to either side and lowered his voice. "Remember why we are here, Bruno. These seminaries in Rheims and Rome are Walsingham's greatest headache at the moment-they have vast funds from the Vatican and are in the business of training dozens of priests for the English mission, many of them former Oxford men." He pulled his beard into a point as he thought, then picked up the book again. "What is this little circle here?" he asked, pointing to the wheel symbol that marked the previous day's entry in Mercer's calendar.

"I don't know. It appears often. I wondered if it might be a code."

Sidney peered closer, then shook his head. "I recognise it, but I can't think from where. Looks like one of your magical symbols, Bruno."

I had not liked to say so, but the thought had crossed my mind; Roger Mercer had secretly confided an interest in magic. Even so, the symbol was not one I recognised, and so it intrigued me.

"It's not an astrological symbol, that is certain," I said. "But that is not the most important thing. Smell the book."

Sidney frowned indulgently, but brought the book close to his face. " Oranges?"

"Yes. Look to the back."

He flicked through the pages, then looked up at me, nodding with something like admiration.

"Good work, Bruno. That is an old trick, the invisible writing in orange juice. Have you found some secret message?"

"A cipher. I made a copy-here." I pushed my piece of paper across the table at him. "You see what he has written at the bottom?"

"Ora pro nobis. Well, well." Sidney folded the paper carefully and handed it back to me. "'Pray for us.' Could be some sort of password or secret sign."

"That's what I thought. Should we inform Walsingham?"

Sidney thought for a moment, then shook his head. "We have nothing to tell him yet, except that we suspect a man, who is already dead, of Catholic affiliations. He would not thank us for wasting his time, and I cannot spare the expense of a messenger to London until we have something better. No-I think you should pursue this as discreetly as you may," he continued, closing the book and handing it back. "Especially if you say Rector Underhill seems keen to have it hushed up-he may know more than he lets on. Just because he was appointed by my uncle it does not follow that he can be trusted-the earl has made mistakes in his judgment before now." He set his lips in a tight line. "And who is this J-have you any thoughts?"

"I have met only three men whose names begin with J," I said. "John Florio, the Anglo-Italian, James Coverdale, the proctor, and John Underhill, the rector. But it may not signify a name. Perhaps it is another coded symbol."

Sidney nodded grimly.

"Perhaps. There is much to think about. But for now, my dear Bruno," he said, suddenly smiling, "you must think only about this evening's disputation. You must dazzle all Oxford with the new cosmology, and put this business from your mind. Lizzy-let me settle this account!" he called, as the serving woman glanced in our direction. "And I will take a large bottle of your strongest ale for the road," he added genially, counting coins from his purse. When she had gone to fetch one, he leaned in and winked. "A little gift for you to take your new friend the porter. I'll tell you this about Oxford -the porters guard more secrets than anyone in the university. Befriend your porter and he will quite literally open doors for you. And now, Bruno," he said, clapping me on the back, "you must go and settle this small matter of whether or not the earth moves around the sun."

I was about to rise and take my leave when a great gale of laughter and chatter erupted from behind us as the taproom door opened to admit a group of four tall young men, all dressed expensively in jerkins of buff leather, silk peasecod doublets, and short slashed breeches to show off their legs in fine silk stockings, all sporting bright starched ruffs above their collars and short velvet cloaks over one shoulder. They carried themselves with an identical swagger, talking loudly in cultured voices, making crude jokes to the serving girl, and when they turned around I realised that the tallest of them was Gabriel Norris. He recognised me and raised a hand in greeting.

"Ah, il gentil doctore!" he cried, beckoning his friends over to our table. "Come, boys, meet my new friend, the renowned Italian philosopher Doctor Giordano Bruno, and-" He stopped suddenly as he looked at Sidney for the first time and smartly executed a low bow, then turned to me expectantly and I realised I was supposed to effect the introductions.

"This is Master Gabriel Norris," I announced, as Norris bowed again, "who so expertly dispatched the mad dog in the garden this morning. This is my friend Sir Philip Sidney."

"You are the brave huntsman, then?" Sidney said, arching an eyebrow in amusement.

"I cannot claim too much praise for that feat, sir-the dog was barely yards from me. I prefer more of a challenge when I draw my bow," Norris replied, with a self-deprecating laugh. "There is good hunting to be had at Shotover Forest, though, Sir Philip, if you are looking for some sport during your stay."

"I'd welcome the chance, if this weather clears," Sidney said. "Norris, you say? Who is your father?"

"George Norris, gentleman, of Buckinghamshire," Norris said, effecting another bow. "But he lived most of his later life in France and Flanders."

Sidney appeared to be consulting some kind of mental register to see if the name meant something. Eventually he shook his head politely.

"Don't know him. France, eh? Exile, was he?"

"Oh, no, Sir Philip." Norris laughed again. "He was a merchant. Cloth and luxury goods. He was exceptionally good at his business." He gave Sidney a broad wink and rubbed his fingers together in the international sign for money. His manner was beginning to grate on me.