Murder by the Book

Chapter 12

The residents of Cambridge were already up and about, many dressed in their best clothes. There was an atmosphere of excited anticipation, for the previous night’s rout had been hailed a success, and people were confident that the raiders would never dare return. Edith waved cheerfully to Bartholomew as she and her husband removed the boards that had covered their windows, while the head of the Frevill clan was ushering his family back into their home.

‘We received word during the night that the town had bloodied the robbers’ noses,’ said Edith, as Bartholomew skidded to a standstill. ‘So we decided to return.’

He was dismayed. ‘But one of our scholars heard the raiders talking, and they plan to strike again today. The danger is far from over!’

Stanmore waved a dismissive hand, and nodded that his wife should begin decorating the windowsills while he dealt with her agitated brother.

‘He probably heard that before we taught them a lesson in the High Street,’ he said with quiet reason. ‘They will not try a third time. They are not stupid, and will know when they are defeated.’

‘But they have not stolen the tax money yet,’ argued Bartholomew. ‘They will not give up so easily when they have invested so much. Moreover, I think they intend to unleash a–’

‘Enough!’ said Stanmore sharply. He lowered his voice, so Edith would not hear. ‘It has been a dismal winter, and this is the first opportunity we have had to enjoy ourselves in months. Do not spoil it with your alarmist notions. There will be no raid today.’

There was no point arguing with such firmly held convictions. With one last, agonised glance at his sister, Bartholomew ran after Michael, who was aiming for King’s Hall in the hope that Walkelate’s colleagues would know where the architect was.

‘Walkelate is not here,’ said Shropham, when they were shown into his office. ‘He has been out all night, but we expected that – he is determined to have his library perfect for today.’

‘Where else might he be?’ demanded Michael.

‘There is nowhere else. The library has been his consuming passion these past few weeks. Of course, there is also his other obsession …’

‘What other obsession?’

‘He is fascinated with artillery and siege warfare, an interest that began at more or less the same time as that beggar was murdered – the one whose throat was cut.’

‘You think he is connected to the invaders?’ asked Michael, struggling to understand what he was being told.

‘Of course not.’ But the Warden’s eyes were uneasy. ‘Yet he has strong opinions …’

‘Shropham!’ shouted Michael in exasperation. ‘Please! We have told you why we need to find him, so do not make this more difficult. Or do you want King’s Hall blamed for whatever happens?’

‘No!’ Shropham was in an agony of conflicting loyalties. ‘Yet I fear Walkelate has done something terrible. About two months ago, he performed a lot of experiments that involved explosions and I had to order him to desist, because he was disturbing our students. I was relieved when the library began to take up more of his time, as I thought it would distract him …’

‘Did he work alone, or with others?’ asked Michael.

‘With Northwood and the Londons,’ replied Shropham. ‘And Vale the physician, too, I believe. They were also interested in alchemy.’

‘Walkelate lied,’ said Bartholomew to Michael, although the monk did not need to be told. ‘He did not stumble across Northwood and the others in Newe Inn – he took them there when King’s Hall became unavailable. Clippesby and Riborowe said they could not identify everyone who assembled in Cholles Lane before slipping into the garden. One of them must have been Walkelate.’

‘Hovering there with a key to let them in,’ finished Michael.

‘I think he has designed a new weapon,’ blurted Shropham. His face was ashen. ‘There were diagrams in his room … I was a soldier myself once, and his pictures look like modified ribauldequins to me. He spent hours discussing such devices with Holm and Riborowe, who were at Poitiers.’

Something dreadful occurred to Bartholomew. ‘Do you think he might have conceived one that can discharge wildfire? As matters stand, the stuff is not very easy to deploy, but if he has devised a contraption that can propel it into the ranks of the enemy …’

Shropham would not meet his eyes. ‘That is exactly what it looked like to me. But I am not too concerned, because no one knows the recipe for wildfire any more. It has been lost, thank God.’

‘The discharge of wildfire from a ribauldequin would certainly be cataclysmic,’ said Michael, exchanging an appalled glance with Bartholomew.

‘There is one more thing.’ Shropham’s expression was one of inner torment: it pained him to tell tales on a colleague. ‘I happened to glance in his room this morning. The drawings have gone.’

‘Why did you not tell us this immediately?’ demanded Michael, horrified.

‘Why would I? Sketching weapons is not illegal, and he has not actually done anything wrong.’

But Shropham did not look convinced by his own argument, and neither were Bartholomew and Michael. Without further ado, they left King’s Hall and hurried into the High Street, feeling that time was slipping inexorably away.

‘Walkelate has not gone to muster his artisans,’ said Bartholomew in despair. ‘He has gone to consort with the robbers – to give them what he has invented. Assuming he has not done so already.’

‘No,’ said Michael, albeit uncertainly. ‘There is nothing to connect him to them.’

‘Yes, there is. Browne heard the raiders talking in Cholles Lane – the place where Walkelate’s helpmeets assembled before they went to experiment. That cannot be a coincidence. Besides, why else would he have taken his diagrams?’

‘Even if you are right, drawings are not the same as an actual device,’ Michael pointed out. ‘He can sell his theory, but he cannot sell the weapon itself.’

‘Dick Tulyet has a ribauldequin,’ said Bartholomew wretchedly. ‘I saw it at the castle. Walkelate was one of several scholars who helped him design it.’

‘Then we need not worry,’ said Michael in relief. ‘If it is in the castle, then the invaders do not have it. And if a ribauldequin is the only way wildfire can be deployed, then they are foiled.’

‘It is stored in the chapel now, but it was in the Great Tower.’ Bartholomew’s thoughts were racing. ‘I suggested that the robbers might have wanted it, but Dick said no.’

‘He may be right, Matt – such a device would not be easy to whisk away in a lightning raid. But forget it for now: we need to concentrate on Walkelate. I doubt he has gone to the Fens, because if he is involved with the robbers, he will know that they are coming here. He will have gone to one of his surviving accomplices. And not Holm, before you say it.’

‘Riborowe has an unhealthy interest in artillery.’ Bartholomew jabbed a finger. ‘And there he is now, slinking along in a manner that is distinctly furtive!’

Riborowe broke into a run when he saw Bartholomew and Michael bearing down on him, his skeletal legs pumping furiously as he tore towards his friary. He moved fast, and had reached St Mary the Great before Bartholomew managed to bring him down with a flying tackle. He struggled, spat and scratched furiously until Michael arrived to help secure him.

‘Walkelate,’ growled the monk, seizing him by the scruff of his neck. ‘Where is he?’

‘I have no idea,’ snapped Riborowe. ‘But if you think to accuse me of helping Northwood cheat the friary over those exemplars, then you have the wrong man. It was Jorz. He was the one who told Northwood how many to expect, and which ones could be declared inferior. He confessed it to me the night he died. He, Northwood and Walkelate were experimenting together.’

‘Then why did you not tell me immediately?’ demanded Michael angrily.

‘Because I am frightened of him,’ shouted Riborowe, jabbing a bony finger at Bartholomew. ‘It was unnerving when he appeared so soon after we discovered Jorz’s corpse, especially given that Jorz had seen him releasing Satan’s familiar by the river.’

Michael grimaced his exasperation. ‘Tell me about Walkelate and his love of weapons.’

‘Why do you–’ Riborowe saw the dangerous expression on the monk’s face and began to gabble. ‘He is especially interested in ribauldequins, and we worked together on the one the Sheriff built for the King. He imposed some peculiar modifications, although he declined to tell me why. He made a second one, too, but I do not know where he keeps it.’

‘A second one?’ cried Bartholomew in dismay. He turned to Michael. ‘Supposing the raiders already have it?’

Michael regarded the Carmelite in distaste. ‘And you accuse Matt of dealing with the Devil! He cures people, while you devise ways to kill them.’

‘I am not the only one,’ bleated Riborowe. ‘Northwood was interested in artillery, too. He pretended to find it shocking, and refused to help the Sheriff, but in reality he was fascinated by it.’

‘Tell me about the second ribauldequin,’ ordered Michael. ‘How is it different from Tulyet’s?’

‘I do not know. Walkelate and Northwood never let me see the final result.’ Riborowe freed himself from the monk’s grasp and backed away. ‘I am going to leave Cambridge today. It is too full of men with alarming ideas. I shall join a convent in another town – one without mad experimenters and Corpse Examiners running riot.’

‘Hypocrite!’ spat Michael, watching him scuttle away. ‘He knows he has contributed to something terrible, but is not man enough to admit it.’

‘Why are you letting him go?’ asked Bartholomew, agitated and unhappy. ‘He is our only lead to Walkelate.’

‘He does not know where Walkelate is, or what his plans are. Walkelate has been using him, pumping him for technical information while telling him nothing in return. And I suspect Walkelate did the same with Jorz, Northwood, Vale and the London brothers.’

Bartholomew was not so sure, but there was no time to discuss it. ‘How do we find Walkelate now?’

‘By interrogating another of his accomplices,’ said Michael grimly. ‘Gyseburne will be–’

‘Holm,’ countered Bartholomew. ‘We should check Holm first because … because he lives nearer, and you are tired.’

Michael shot him a rueful glance for his transparency, but turned towards Cholles Lane anyway. All along the High Street, houses were being bedecked with red blossoms, and the churches had their doors open. The flowers smelled strong, and Bartholomew was uncomfortably reminded of Ayera and his penchant for poisonous blooms. Everywhere, people were greeting each other cheerfully, and scholars and townsfolk alike were girding themselves up for fun.

‘You must postpone the library’s opening – at least, until we find Walkelate,’ said Bartholomew.

Michael nodded. ‘Yes. Although Dunning will never forgive us …’

‘Tell Dick to cancel the pageant, too. Every dignitary and cleric in Cambridge plans to take part in it, while virtually every man, woman and child will be watching. We cannot let it go ahead when we fear an atrocity in the making. It would be immoral.’

‘What about the plan to lure the raiders here, so we can engage them in battle?’ panted Michael. ‘They will not come if the ceremonies are called off, and Shropham was right – we cannot endure weeks of uncertainty while we wait for their next assault.’

‘Dick thought Shropham’s plan reckless, and so did Dame Pelagia. The Guild of Corpus Christi has supported it, but only because cancelling the event will lose them money. Dick should do as he suggested last night – declare a state of military law until the robbers have been caught.’

Michael was silent for a moment, then burst out with, ‘But wildfire, Matt! I do not think that Walkelate would unleash such a terrible substance on us.’

‘He took two of the most wicked weapons ever to be invented, and combined them. How can you even think that such a man has a conscience?’

Michael waylaid two passing beadles, and sent one to the castle with the recommendation that the Sheriff postpone the pageant, and the other to Dunning, to explain why he was going to be deprived of his moment of glory. Then he and Bartholomew ran the short distance to Holm’s house, which they found with all its windows shuttered and its door closed. They exchanged a glance: was the fact that the surgeon had declined to lower his guard evidence that he knew what was about to befall the town?

‘I will wait a few moments, then knock,’ said Michael. ‘You go around the back, to make sure he does not escape. Here is a dagger.’

Bartholomew had not known Michael was armed, and was unsettled that the monk should think such draconian measures necessary. Without a word, he took the weapon, and eased down a smelly alley until he reached a gate. It was unlocked, so he opened it and stepped into Holm’s yard.

He was startled to see the surgeon slumped over a garden table. There was no sign of Walkelate. He approached cautiously, and saw a lump on the back of Holm’s head; ropes secured his hands and feet. He felt for a life-beat, and at his touch, Holm’s eyelids flickered open. The surgeon moaned and cursed his way back to wakefulness, while Bartholomew struggled to unravel the knots.

‘Who did this to you?’ asked Bartholomew urgently. ‘Quickly, man! Speak!’

‘Walkelate,’ groaned Holm. ‘It happened last night, and I have been stuck out here ever since. Thank God you came to save me.’

‘Why did he hit you?’ demanded Bartholomew, agitation and concern making him rougher with the ropes and his questions than he might otherwise have been.

‘You are unsympathetic, because of Isnard,’ said Holm sullenly. ‘He claims I tried to poison him, because it transpires that he is innocent of wrongdoing and I owe you five marks.’

‘Never mind that,’ said Bartholomew. ‘Do you know–’

‘But I only used a mild dose of henbane,’ Holm went on. ‘I would not have given him any, but he was gloating about me having to pay you, and I could not help myself.’

Bartholomew gaped at him. ‘Isnard was right? You did try to dispatch him?’

‘Not dispatch,’ corrected Holm, rubbing his abused wrists. ‘Teach him a lesson. And I shall give you your five marks as soon as I am married.’

‘You will pay me from Julitta’s dowry? I hardly think that is right.’

‘No?’ pounced Holm. ‘I am glad you think so. I shall keep it for myself, then.’

It was no time to discuss money. ‘Did you know that your lover is a murderer? He has just confessed to killing several scholars in order to frighten them out of libraries.’

Holm squinted up at him, and Bartholomew felt uncharitably disappointed when he saw the astonishment in his eyes. He could tell it was genuine. The surgeon blew out his cheeks as he assimilated the information.

‘Well,’ he said at last. ‘Who would have thought it? I know he was always saying that times are hard, but to kill to make them better … Oh, well. I was beginning to tire of him, anyway, and I can do a lot better for myself, even if his cousin does know the King.’

Bartholomew did not care about the surgeon’s ambitions. ‘Where is Walkelate now?’

‘I have no idea. And I cannot imagine why he hit me, either. All I did was offer to spruce up his library – I decided it would do my reputation no harm to be associated with the finished product, you see. Besides, it was an excuse to be away from the annoying Julitta.’

With difficulty, Bartholomew ignored the last remark. ‘He hit you for wanting to help him?’

At that moment, Michael appeared. ‘The door was unlocked, so I–’ He gaped in confusion when he saw Holm holding his head and the ropes on the ground. ‘What happened?’

‘I suppose I was rather insistent,’ admitted Holm, continuing to address Bartholomew. ‘However, he did not have to resort to violence. I would have desisted eventually.’

‘He could not take the risk that you would foist yourself on him anyway.’ Bartholomew spoke more to himself than the surgeon. ‘I suspect he had a lot to do last night. Tell us what you recall.’

‘Me begging to accompany him, and him saying that he was too busy. I told him I did not require entertaining, and I suppose we quarrelled. The next thing I knew was him coming at me with the hilt of a dagger. I am lucky he did not skewer me.’

‘You hired singers to entertain the craftsmen at Newe Inn the night Northwood and the others died,’ began Michael. ‘Why did you choose that particular night to be generous?’

‘Because Walkelate said it would be a kindness, and I was keen to stay on his good side. He is an important member of King’s Hall, as I have said before.’

Again, Bartholomew knew Holm was telling the truth; the open selfishness had the ring of honesty about it. ‘Clearly, Walkelate wanted to drown out any sounds his accomplices might have made doing God knows what in the garden,’ he said to Michael.

‘Yes,’ agreed the monk. ‘And now we had better look for him in Gyseburne’s home, where we should have gone in the first place.’

‘He will not be there,’ said Holm. He shrugged rather sheepishly. ‘Ayera told me a tale that Gyseburne’s mother is a witch, and I repeated it to Walkelate, thinking he would find it amusing, but he was appalled, and has avoided the fellow ever since. But why are you so eager to find him?’

‘Because it transpires that he has an unsavoury interest in artillery,’ explained Michael tersely. ‘And because we fear that he may be in league with men who want to use some on our town.’

Holm considered the accusation, then nodded slowly. ‘He might. He is interested in armaments, and he has been meeting villainous men for weeks. French-speaking men. I overheard him arranging to sell them something a fortnight or so ago. He told me that they were visiting scholars from Paris, but I did not believe him. They were warriors without a doubt.’

‘We have not had visiting scholars from Paris for months,’ said Michael immediately, who as Senior Proctor was in a position to know.

‘Are you saying that the raiders are French?’ asked Bartholomew, bewildered. But then he recalled that the ones he had encountered had spoken that language.

‘Well they are rather more than common brigands,’ said Holm curtly. ‘Or they would not be so damned persistent.’

Bartholomew struggled to understand what he was hearing. ‘We think Walkelate has invented a wildfire-spitting ribauldequin, and we are at war with France. Selling Frenchmen weapons – or even plans and formulae – amounts to treason!’

‘Only if he is caught,’ said Holm. ‘And he told me himself that he is cleverer than you.’

‘I thought he was your friend,’ said Michael, before Bartholomew could point out that siding with the French at Poitiers had hardly been an act of patriotism. suspicious of the surgeon’s disloyal revelations. ‘How can you betray his confidences so readily?’

‘He forfeited my friendship when he hit me on the head,’ said Holm with a pout. ‘Besides, I have my reputation to consider. I do not want to be associated with treason.’

‘Think very carefully,’ instructed Michael, before Bartholomew could point out that siding with the French at Poitiers had hardly been an act of patriotism. ‘Can you suggest anywhere he might be? He is not at King’s Hall or his library.’

Holm frowned, still rubbing his wrists, while Bartholomew struggled with the urge to grab him by the throat in an effort to speed up his ponderings.

‘Try the Carmelites’ scriptorium,’ he said eventually. ‘He mentioned buying some labels there.’

‘Go to the castle and tell the Sheriff everything we have just reasoned,’ ordered Michael, turning to leave. ‘Even the parts you do not understand. It is a matter of life and death, so do it immediately – as quickly as you can run.’

‘He will not oblige,’ said Bartholomew, regarding the surgeon with loathing. ‘Just as he did not bother to raise the alarm when Rougham and I were accosted. He ran straight home and shut himself safely inside. If he had been braver, we might have been rescued before Rougham revealed the secret of wildfire to what we now suspect were French spies!’

‘That was different,’ objected Holm indignantly. ‘It was dark then, and I was frightened.’

‘You will do as I ask,’ said Michael sharply. ‘Or you may find your wealthy bride-to-be hears certain nasty truths about her beloved fiancé.’

Holm’s face was a mask of furious resentment as Michael turned on his heel and stalked out. Bartholomew stared at him for a moment, then followed.

‘We cannot trust him, Brother,’ he warned. ‘He is more likely to run straight to Julitta, and start spinning yarns as to why your accusations are untrue.’

‘He would not dare.’ Michael broke into the waddle that passed as a run for him. ‘He knew my threat was in earnest. Besides, what else can we do? We do not have time to explain everything to another messenger. Holm will come through, Matt. He has too much to lose by failing.’

Bartholomew was unconvinced, but they had reached the Carmelite Priory, and he was obliged to turn his thoughts back to Walkelate. The convent was deserted; the friars and their servants were in the chapel, singing gustily as they performed the first of many offices that would take place that day. He and Michael tore across the yard to the scriptorium. It, too, was empty, except for one man who was busily rifling through some ledgers, his hands stained red with ink.

‘Langelee!’ they exclaimed in unison.

Bartholomew and Michael were so astonished at seeing the Master that neither spotted the figure that had been loitering in the shadows until it emerged with a sword at the ready. It was Ayera, unshaven, dishevelled and tense.

‘Damn,’ he murmured softly. ‘Now what?’

‘Now they help us,’ said Langelee, beckoning Bartholomew and Michael forward. ‘Because we cannot do this alone.’

‘Help you do what?’ asked Michael warily, declining to move.

‘Foil the men who are determined to betray our country,’ replied Langelee, turning back to the ledgers. ‘Ayera and I have been racing about blindly for days now, and we are at our wits’ end.’

‘I know the feeling,’ said Michael icily, still not moving. ‘What is going on?’

‘Walkelate has invented a ribauldequin that can eject wildfire,’ explained Langelee tightly. ‘And we believe he has gone some way to producing wildfire itself. He and his cronies have been experimenting with the stuff in Newe Inn’s garden.’

‘Who are his cronies?’ asked Bartholomew, acutely aware that Ayera had not sheathed his sword, and that it hovered unnervingly close to his back.

‘Enough questions,’ said the geometrician sharply. ‘I do not like this.’

‘Northwood, the London brothers, Vale, Jorz and possibly others,’ replied Langelee, ignoring him. ‘Although I doubt any of them knew what they were doing, or what Walkelate intended to do with the formula once he had it. They have been mercilessly used. And all are dead, of course.’

‘Jorz drowned in a bowl of red ink.’ Michael looked pointedly at Langelee’s scarlet hands.

‘Knocked on the head first, though,’ said Langelee. ‘Otherwise there would have been too much splashing. Knocking people on the head is becoming quite a habit with Walkelate. I now know that it was he who attacked me in Newe Inn’s garden. Ayera found out.’

‘I overheard him telling Frevill about it,’ explained Ayera, although he spoke reluctantly.

‘How do you know Jorz was knocked on the head first?’ asked Bartholomew of Langelee.

‘Because I was spying here, and I saw it happen. I raced to help him the moment Walkelate had left, but it was too late. And I splattered ink all over myself into the bargain.’

‘Are you saying you delayed before going to Jorz’s assistance?’ asked Bartholomew uneasily. ‘You stood in the shadows watching while murder was committed, and only emerged when the killer had gone?’

Langelee waved a dismissive hand. ‘I could not afford to let Walkelate see that he was discovered lest he went to ground. And then we would never have answers. Still, at least one thing is clear: I now know why Northwood quizzed me so relentlessly about my battlefield experiences – he wanted information to share with those damned raiders.’

Michael turned suddenly to Ayera, who took an involuntary step backwards when he saw the dark expression on the monk’s face. ‘We have it on good authority that you were among the raiders, too. Walkelate might be betraying his country, but you have betrayed our town.’

Ayera regarded Langelee with weary resignation. ‘Did you tell them?’

Langelee looked indignant. ‘Of course not. However, I did say that you would be unlikely to deceive Michael, and that you should take him into your confidence. You should have listened.’

‘What is going on?’ snapped Michael. ‘And you can put down that blade, Ayera, because we all know you will not use it on us.’

Bartholomew knew no such thing, and waited, taut as a bowstring, while Ayera stared at the monk. Then the geometrician sighed, and the sword dipped towards the floor.

‘I did join ranks with the robbers, but I had my reasons.’

‘I suppose you wanted money because your uncle failed to bequeath you any,’ surmised Bartholomew coldly. ‘And you were eager to buy that horse.’

‘It is a little more complex than that,’ said Ayera shortly.

Michael folded his arms. ‘Then explain.’

‘Perhaps one day,’ said Ayera. ‘But not now.’

Michael took an angry step towards him. ‘That is not good enough.’

‘Leave him be,’ came a voice from the door. ‘He cannot tell you what you want to know, because he is under orders to keep his silence. You see, he is in my employ, as is Master Langelee.’

Bartholomew spun around, Michael’s dagger in his hand, but lowered it quickly when he recognised the speaker. It was Dame Pelagia.

‘At last!’ cried Langelee in relief. ‘Where have you been, madam? We need more directions, because Ayera and I are hopelessly out of our depth here.’

Michael gaped at his grandmother, still struggling to understand. ‘They are working for you?’

Pelagia inclined her head. ‘Ayera has been with me for a while now, ever since the King decided it was time I had an assistant to perform some of my more physically demanding duties.’

‘Ayera is your apprentice?’ Michael looked as astonished as Bartholomew felt.

Pelagia nodded again. ‘And he recruited Langelee when we needed more help.’

‘Why Langelee?’ demanded Michael indignant and hurt. ‘Why not me?’

‘Because Langelee is a warrior,’ explained Ayera. ‘We fought together at the Battle of Neville’s Cross, and we were friends in York. You are a brave and intelligent man, Brother, but I needed a soldier.’

‘Ayera joined the raiders on my orders,’ said Pelagia, when Michael was silent. ‘He told them he needed the pay because he feared his uncle’s bequest would prove to be a disappointment.’

‘It did prove to be a disappointment,’ said Ayera ruefully. ‘My family lending me money for that horse is not the same at all.’ He turned to Bartholomew. ‘I am afraid I did not handle your questions very well, Matt. You caught me off guard, and I suspect my answers did nothing to alleviate your concerns.’

‘And I am sorry I threatened to restrict your access to patients,’ added Langelee. ‘But it was the only way I could think of to bring an end to the discussion. You kept catching us in inconsistencies – such as whether Ayera found me wandering dazed in Cholles Lane or in Newe Inn’s garden – and I had to end it before it went any further.’

‘It was Ayera who saved my life last night!’ exclaimed Bartholomew in sudden understanding. ‘Frevill was about to kill me in the scuffle outside King’s Hall, but Ayera threw a knife. The shadow was too large to be Dame Pelagia.’

‘Now you know why I am so certain that there will be an attack today,’ said Pelagia, as Ayera shot the physician a brief smile of acknowledgement. ‘Ayera heard it from the raiders’ own lips. We must do all we can to prevent it, so–’

‘Yes, but I still have questions,’ interrupted Michael. ‘Clippesby saw Ayera talking with the villainous Willelmus during the attack on the castle–’

‘Of course I spoke to him,’ said Ayera impatiently. ‘I needed to know what intelligence he had passed to the robbers. I did my best to win their confidence, but they never did trust me fully – especially after the first raid, when my premature battle cry gave the defenders time to grab their bows.’

‘You should have told me all this,’ said Michael accusingly to Pelagia. ‘Here is a terrible plot unfolding in my town, and you chose to keep me in the dark.’

Pelagia laid a conciliatory hand on his arm. ‘I did not know until a few hours ago that the four scholars in the library pond were connected with my mission here – or that Walkelate was the arch-villain. Meanwhile, you had several suspicious deaths to unravel, and two factions of querulous academics to hold apart. I admire your skills greatly, but you are only one man.’

‘You do?’ asked Michael, the wind taken out of his sails. Praise from Pelagia was not dispensed very often.

She smiled briefly, then became businesslike. ‘It seems that all our cases have converged – my French spy, the lunatic scholar-inventors whom Ayera has been monitoring, and Michael’s Newe Inn deaths – so it makes sense to join forces.’

‘What French spy?’ asked Bartholomew, puzzled.

A frown of impatience crossed Pelagia’s face. ‘The one I have been tracking for the past few months, and who I now know is commanding these raiders. There is no time for more detailed explanations. Now tell me what you have learned.’

Michael obliged, painting a succinct but detailed account of Walkelate’s dealings.

‘His Majesty has known for weeks that a few Cambridge scholars have turned their talents to designing weapons,’ said Pelagia, when he had finished.

Michael gaped at her yet again. ‘How? I did not!’

‘Because he had heard that a group of Oxford men had come here and bragged about their achievements, and he guessed that Cambridge would aim to outdo them. He asked me to monitor the situation, but an elderly woman is not the best person to infiltrate a community of male scholars, so I sent my trusty assistant to do it for me.’

‘Langelee enrolled me as a Fellow in January.’ Ayera took up the tale. ‘The cover has worked brilliantly, because no one suspects that a University geometrician – one of their own Regents – is a government spy. Then, about two months ago, I heard whispers that some scholars were devising a new and deadly weapon …’

‘He also heard tales that strangers were gathering in the marshes, recruiting men who were willing to risk their lives for quick gold,’ added Pelagia. ‘Ayce, Coslaye …’

‘I sent for Dame Pelagia at that point,’ said Ayera. ‘And I warned the King. But she was busy with her French spy, and it took some time for my message to reach her. She only arrived here a few days ago.’

‘We had better discuss this later,’ said Bartholomew, more interested in averting a catastrophe than satisfying his curiosity. ‘Something terrible is going to happen – and soon.’

‘You are quite right,’ agreed Pelagia. ‘Ayera learned last night that the robbers plan to make another assault on the taxes. This will achieve two things: first, provide a diversion so that Walkelate can hand over his ribauldequin and wildfire; and second, allow them to recoup their losses – this whole operation has been very expensive.’

‘Do they still believe the taxes are in the castle?’ asked Michael urgently. ‘Or will they assault King’s Hall again?’

Ayera grimaced. ‘Unfortunately, Walkelate was party to a conversation in the stationers’ shop, during which the Senior Proctor denounced the rumour about the taxes being moved as a ruse. The robbers now know that they are in the castle, which is a pity. It was better when they thought they might have to search eight Colleges, forty hostels and half a dozen convents.’

‘We must warn Tulyet,’ said Bartholomew, as Michael winced. ‘He needs to prepare.’

‘He is as ready as he ever will be, and the town can be taxed again should he fail to repel these rogues,’ said Pelagia, coldly professional. ‘It is far more important to ensure that Walkelate’s invention does not fall into French hands. Forget the castle, and concentrate on him.’

‘But the taxes include a ribauldequin,’ argued Bartholomew, ‘which is in the castle chapel.’

‘It is true,’ Ayera told her. ‘I was told not an hour ago that we mercenaries will be given a hefty bonus if we acquire it in addition to Tulyet’s chests of money.’

‘Yes, but Walkelate made two ribauldequins, not one,’ said Pelagia. ‘And it is the hidden one that can deploy wildfire – Tulyet’s is just like any other.’ She nodded to the ledgers that Langelee was still rifling through. ‘Have you discovered anything in those to tell us where it might be?’

‘It is not in King’s Hall,’ said Ayera, when Langelee shook his head. ‘I searched it thoroughly.’

‘It must be in the Common Library,’ said Bartholomew suddenly. ‘Walkelate spends every waking moment there, so it stands to reason that he has been doing more than overseeing the construction of shelves. We should go there now and search for it. All of us, together.’

‘It is as sensible a notion as any,’ said Pelagia, indicating that he should lead the way.

Pelagia lagged behind as they ran to Newe Inn, reminding Bartholomew that while she seemed an unstoppable force, she was actually an elderly lady who could hardly be expected to keep pace with men less than half her age. Ayera fell back to walk with her, but she waved him on with an impatient flick of her hand. When he ran to catch up with the others, Bartholomew noticed that he was limping.

‘Yes,’ the geometrician said, seeing what he was thinking. ‘I was injured during the raid on the castle. I had to fight Tulyet’s men, or my cover would have been lost.’

‘Speaking of Tulyet, Holm and my beadle will have reached him by now,’ said Michael. ‘After he has cancelled the pageant, he will almost certainly aim straight for Cholles Lane, because he will want more detailed answers from us. We shall soon have help in confounding these villains.’

‘If he does, he leaves the castle vulnerable,’ said Bartholomew worriedly. ‘And Dame Pelagia just said that grabbing the taxes is the diversion Walkelate needs to pass his weapon to the French.’

‘He has not cancelled the pageant,’ said Ayera, gesturing around him at the empty streets, and cocking his head at a distant cheer. ‘The warning must have arrived too late.’

With despair, Bartholomew saw he was right. The town was virtually deserted: everyone had gone to the Guild Hall to watch the start of the ceremonies. A few drunkards lounged outside an alehouse, and two dirty boys slunk along carrying a trussed goat between them, but there was no other sign of life.

‘Lord!’ he muttered. ‘It is a perfect opportunity for a hostile force to wade across the river or the King’s Ditch – both are low, because of the recent dry weather. And Dick said the ditch is so full of silt that it is possible to walk–’

‘Hurry!’ interrupted Langelee urgently. ‘We must find and destroy this infernal machine, no matter what the cost to ourselves.’

He and Ayera drew their swords when they reached the library, and he indicated that Bartholomew and Michael should arm themselves, too. A heavy stick appeared in the monk’s beefy paw, while Bartholomew had his childbirth forceps in one hand and Michael’s dagger in the other. Treading with silent grace, Ayera led the way up the spiral staircase, turning to glare when Michael trod on a creaking floorboard.

They arrived upstairs and peered around the door to see Walkelate in the larger of the two rooms. A number of men were there with him. All wore armour, and they were unquestionably the raiders. One was limping from what appeared to be a wound in his thigh. They were cloaked and hooded, and Bartholomew knew, without the shadow of a doubt, that they were the men who had ambushed him. Mentally, he cursed Rougham again for caving in to their threats, but then supposed it was irrelevant if Walkelate had discovered the formula independently, anyway.

‘There is no need to incinerate the castle, Rougé,’ Walkelate was saying. ‘The pageant will provide a perfectly adequate diversion for you to leave Cambridge with the weapon.’

‘Unfortunately, the tales of our imminent arrival have made the Sheriff overly vigilant,’ replied Rougé. His French was flawless, indicating that he was a native speaker. Bartholomew gaped when the man turned, and he saw his face. ‘So bombarding the castle with fire-arrows is necessary to keep him busy. We cannot let him foil us – too much is at stake. Besides, I want the tax money.’

‘We cannot tackle all these soldiers alone,’ whispered Michael, drawing back a little to speak. ‘I am no coward, but I see no point in suicide.’

‘But you just said that Tulyet will be on his way,’ Langelee whispered back. ‘I am sure we can keep these paltry villains busy until he arrives. Eh, Ayera?’

‘He will not come if he is being barraged with burning arrows,’ hissed Michael, although Ayera raised his sword in a salute and grinned rather diabolically. ‘Come away. We cannot achieve anything by staying here.’

‘We will listen, then,’ hedged Langelee. ‘But if I say we must attack, you had better be ready. You, too, Bartholomew. The experience you gained fighting at Poitiers will be vital today.’

Bartholomew was horrified, knowing his meagre abilities would not match up to the Master’s expectations, but Langelee waved him to silence when he started to object, and eased forward again.

‘No one believes you will strike today, Rougé,’ Walkelate was saying. ‘I enlisted Weasenham’s unwitting help – I got him to tell everyone that you are licking your wounds and will not be back. Even Oswald Stanmore believes it, and he is less gullible than most. My ploy worked.’

‘Why does he call him Rougé?’ whispered Michael. ‘That is Bonabes the Exemplarius.’

‘Bonabes is French,’ said Ayera in a low, disgusted voice. ‘And I can tell by the way he carries himself that he is a skilled warrior. Moreover, his weapons are of excellent quality, and well honed.’

Even Bartholomew could see that. He recalled the incident at the castle, when Bonabes had claimed to be out of practice when Holm had insisted that he wore an ancient sword to protect them. The Exemplarius was an accomplished liar, because he had been convincing.

‘The merchants might believe you,’ Bonabes was saying. His amiable demeanour had been replaced by something hard and ruthless. ‘But Tulyet does not.’

‘It does not matter what Tulyet thinks,’ said Walkelate impatiently. ‘My carpenter Frevill has used his family connections to ensure that the Guild of Corpus Christi has ignored Tulyet’s worries, leaving him effectively isolated. Besides, he is hopelessly confused. I was rather clever to start the rumour that your little army hails from inside the town, because he does not know where to look for his enemies and–’

‘Rumours!’ spat Bonabes in distaste. ‘There have been so many of them that even I have wondered which were truth and which were lies. But never mind this. Is the weapon ready?’

‘It is in the cista,’ replied Walkelate. He smirked. ‘All manner of folk have used it as a table and workbench, but no one has thought to look inside. What a shock they would have had if they did! I always say that the best hiding places are those in plain sight.’

‘Yet it is an obvious feature, and people will ask where it has gone once we take it. How will you explain its disappearance without incriminating yourself?’

Walkelate’s smile was smug. ‘I shall set a small fire in the corner of this room – not enough to cause serious harm but enough to mask the departure of the cista. I shall say it was started by a stray fire-arrow. After all, we had better sustain some damage in this raid, or folk will be suspicious.’

‘A fire?’ asked Bonabes, startled. ‘With all this wood? Is that wise?’

‘I can control a small blaze,’ said Walkelate haughtily. ‘I am a skilled experimenter.’

‘Show me the weapon again,’ said Bonabes, shrugging to show he did not care what happened to the library. ‘I want to see it one more time.’

Walkelate opened the cista, and by craning forward, Bartholomew could just make out a compact machine with several barrels. It looked like the Poitiers ribauldequins, but Walkelate’s had bulbous mouths, presumably to allow the wildfire to splatter in a wider arc. There was a waft of something unpleasant, too.

‘This pot contains a sample of my other creation,’ said the architect, handing it to Bonabes. ‘I told you there was no need to bother with the physicians. Not only have I reinvented wildfire, but my recipe is far superior.’

‘And you did it alone?’ asked Bonabes. ‘We cannot afford witnesses.’

‘I had to enlist associates, but none are alive to tell the tale.’

Bonabes regarded him narrowly, and his voice turned soft and a little dangerous. ‘Do these dead associates include the London brothers and Northwood? I was fond of them.’

‘They were talented alchemists, and I needed their expertise,’ said Walkelate sharply. His expression became sly. ‘Their deaths were not my fault, anyway – any more than Adam was yours.’

Bonabes flinched, indicating that his affection for the boy-scribe he claimed to have loved like a son had been genuine. He turned his attention to the pot. ‘It took you long enough. Weeks. And even then, you only succeeded after I forced Rougham to name rock oil as the missing ingredient, and procured you some from Weasenham.’

Walkelate regarded him coolly. ‘You told me it was important not to arouse anyone’s suspicions, so of course I took longer than if I had been granted a free hand. Besides, I did better than you – you have come nowhere near a solution for making paper. And anyway, I was not aware that you were in a hurry.’

‘Of course I am in a hurry,’ snapped Bonabes. ‘Not only is France desperate for a miracle, but working for Weasenham has been torture. It was agony, pretending to be subservient to such a man. The only saving grace is Ruth, and I am coming back for her when this is over.’

‘I still do not understand why you hired all those mercenaries,’ said Walkelate after a moment. ‘Our business could have been managed much better without them.’

‘It could not. Pelagia’s spies would have discovered us in an instant without the confusion they provided. They were an absolute necessity. Moreover, I have enjoyed myself, doing to your town what Englishmen have been doing to France for the past three decades. Now your people know what it is like to live in constant fear.’

Bartholomew grabbed Langelee’s arm. The Master, patriotic soul that he was, was finding the discussion hard to stomach. Meanwhile, Bonabes nodded to his men, who sealed the cista, then lifted it, straining under its weight.

‘France owes you a debt of gratitude, Walkelate,’ he said with a smile that was neither friendly nor sincere. Bartholomew suspected the architect would not live long to enjoy the fruits of his labours. ‘This may turn the tide of the war.’

‘I do not want your gratitude,’ said Walkelate. ‘I want your money. I spent funds I do not have perfecting my library, and I cannot allow it to be tainted with the reek of debt.’

At that point, Langelee wrenched away from Bartholomew and exploded into the room, sword at the ready. Ayera rolled his eyes, but went to stand next to him, shoulder to shoulder.

‘This diabolical weapon is not going to France,’ Langelee snarled. ‘Your game is over.’

The men holding the cista dropped it in alarm, and fumbled for their weapons as Langelee tore towards them with a battle cry that hurt the ears. Ayera dropped into a defensive stance as several mercenaries advanced on him, while Michael waved the cudgel around his head. Bartholomew gripped his childbirth forceps more tightly, although he did not hold much hope of besting trained warriors, and as far as he was concerned, Langelee had just signed their death warrants.

But it was no time to apportion blame, because Walkelate’s fine library was full of the sounds of a frantic skirmish. Langelee was yelling furiously, and the clash of his sword against his opponents’ was ear-splitting as he laid about him with wild abandon. Ayera fought more steadily and rationally, and two raiders quickly fell under his scientific blade.

Bartholomew and Michael were less adept, although the physician managed to knock one man senseless, and break the fingers of another. But the odds were too heavily stacked against them, and it was not long before both were pinned against the wall with knives at their throats.

His stomach lurched when he saw blood spurting from a wound in Ayera’s neck. Horrified, he tried go to his colleague’s aid, but his captor dealt him a stinging blow that made him see stars. By the time his vision cleared, Ayera was dead and Langelee was a prisoner, too, breathing hard and glowering furiously at the three soldiers who kept him in place with the tips of their swords.

‘You will not get away with this,’ the Master snarled. ‘Dame Pelagia knows all about you and your plans.’

‘You should have killed her when she fell into your hands, Rougé,’ said Walkelate angrily. ‘As I recommended. But no, you insisted on taking her to the marshes. And what happened? She escaped, and will continue to be a danger to us.’

Bonabes only indicated that his men were to lift the cista, but one of its handles had been broken in the scuffle, and he fretted impatiently while they fashioned a replacement with a belt.

‘Why does he call you Rougé?’ asked Michael. He sounded calm, although Bartholomew was in an agony of tension, appalled by what had happened to Ayera – and by what might befall their country now the ill-advised attack had failed.

‘I am Bonabes, Sire de Rougé et de Derval,’ replied Bonabes haughtily. ‘Vicomte de la Guerche and Châtelain de Pontcallec. And a loyal subject of His Majesty King Jean of France.’

‘But the Sire de Rougé was taken prisoner after the Battle of Poitiers,’ said Langelee in confusion. ‘And is locked in the Tower of London until a ransom can be paid.’

‘I escaped,’ said Bonabes coolly. ‘But I was still on Poitiers field when I determined to acquire a ribauldequin and learn the secret of wildfire. And God is with me, for it cannot have been by chance that I heard about your University and its scholars’ inventions.’

‘Northwood,’ said Bartholomew in disgust. ‘He was at Poitiers: he told you about us.’

Bonabes inclined his head. ‘He came to the Tower a few months ago, to ask after my welfare – we had become acquainted on the journey there, you see. He was a chaplain, and had been given the care of the French captives’ souls. We became friends.’

‘He helped you escape,’ surmised Bartholomew. ‘But why would he do such a thing?’

‘Academic glory,’ replied Bonabes. ‘I promised to finance certain alchemical projects.’

‘Do not waste time in idle chatter,’ hissed Walkelate. ‘They would not have burst in here if beadles and soldiers were not far behind. Kill them, and take your weapon before it is too late.’

‘How will you explain the presence of corpses in your library?’ asked Bonabes, gritting his teeth in frustration when his soldiers grabbed the cista and the new handle snapped. ‘It is due to open soon.’

‘I shall dump them in the pond. I intend to live here and enjoy the adulation of grateful scholars, so you can trust me to do it properly. Not like last time, when I slipped up with Vale.’

‘Yes, kill them,’ came another voice from the door. ‘We cannot afford loose ends.’

‘You?’ gasped Langelee, while Bartholomew sagged in despair. How much deeper did the rot of treachery run in Cambridge?

‘We should have known that Dunning was involved,’ he said tiredly. ‘Developing weapons is expensive, and Walkelate has just said that he needs Bonabes’s blood-money to prevent the library starting its life in debt. Dunning funded the experiments. It explains why he was always here – not assessing the progress of the library, but the progress of the weapon.’

Dunning shrugged. ‘I never liked this building, and Walkelate needed somewhere to work. It was a convenient arrangement for all, and the University will benefit, so do not complain.’

‘Julitta,’ said Bartholomew wretchedly. ‘It was her idea to give us Newe Inn.’

‘She knows nothing of this,’ said Dunning sharply. ‘She would disapprove. She believes my generosity will leave me poor, but the money I shall make from selling Walkelate’s weapon today will make me fabulously rich. And then I shall head the Guild of Corpus Christi.’

‘So that is why you have insisted on a grand opening ceremony today,’ said Langelee in utter disgust. ‘And why you have spent so much time planning the pageant. You have been preparing the ground for your election as Guild Master.’

‘Yes and no,’ replied Dunning. ‘I do want the pageant and the opening ceremony to be a success – and the beadles you sent to order them cancelled have been dealt with, by the way, Brother – but I also need them to serve as a diversion for our other business today.’

‘At least we know now why everyone here was always so tired,’ muttered Michael. ‘Working on the library all day, and labouring over weapons all night …’

‘Iron filings,’ said Bartholomew suddenly. ‘Kente thought they were from metal brackets to fit bookcases to the walls, but they were from the ribauldequin.’

‘Tulyet’s blacksmith unwittingly provided me with a basic set of barrels.’ Walkelate was unable to resist a brag. ‘But it was still necessary to make one or two fine adjustments–’

‘Why did you not kill Michael and Bartholomew when they came here asking after Frevill yesterday?’ interrupted Bonabes, turning on Dunning. ‘You must have seen it was too risky to leave them alive.’

‘I did not have a sword with me,’ snapped Dunning. ‘Why do you think Walkelate sent them to the stationer’s shop? So you could do the honours. But you did not oblige, either.’

‘Ruth was there,’ said Bonabes angrily. ‘How could I?’

‘You are going to be disappointed, Dunning,’ said Langelee, making no effort to conceal his contempt. ‘Because any funds Bonabes has will be used to pay his mercenaries and to transport the weapon to France. Betraying your country will not make you wealthy.’

‘The King’s taxes are more than enough to cover all our needs,’ said Dunning comfortably. ‘The rest of Bonabes’s men are securing them for us as we speak.’

‘If they can find them,’ goaded Langelee. ‘Tulyet has hidden them, and not even his most trusted warriors know where. You will never have them. He has concealed his ribauldequin, too.’

Bonabes regarded Dunning in alarm, and there was consternation among the mercenaries, too. ‘Is this true? Our arrangement stipulates that I am to have both weapons.’

‘Langelee is lying,’ said Dunning coldly. ‘And I want to hear no more of his tales. Kill them.’

There was nothing Bartholomew, Michael or Langelee could do as they were forced to kneel in a line. One mercenary stood behind them, executioner style, and drew his sword. His cool proficiency indicated it was a task he had performed before.

‘Wait!’ shouted Michael. ‘You have not killed anyone, Walkelate. It is not too late to turn back.’

‘But I do not want to turn back,’ said Walkelate, grabbing a handful of kindling from the hearth. ‘I have learned a lot from my experiments, and I can make a significant contribution to the alchemical sciences now. And what is more important than the advancement of knowledge?’

‘What are you doing?’ asked Dunning, watching the architect in bemusement.

‘He has killed, Michael,’ said Bartholomew in disgust. ‘He poisoned his helpmeets. You just heard him admit that he hid their bodies in the pond.’

‘It was an accident,’ objected Walkelate, casting an uneasy glance at Bonabes, whose eyes had narrowed. ‘How was I to know that red lead is toxic when heated?’

‘Of course you did,’ said Bartholomew scornfully. ‘It is basic alchemy. You knew exactly what would happen, and you even persuaded Holm to hire singers to drown the sounds of their final agonies. You condemned them to horrible deaths with calculated and ruthless efficiency. And Northwood and the London brothers were men Bonabes was fond of.’

But his effort to cause friction failed: Bonabes was too determined to have his weapons to allow himself to be distracted by the mere murder of friends.

‘For God’s sake,’ he snapped to the executioner. ‘What are you waiting for?’

‘Jorz was no accident, though,’ said Bartholomew, twisting to one side, and thus spoiling the man’s aim. Impatiently, he was tugged upright again.

‘He grew suspicious of me,’ explained Walkelate. ‘So I had no choice. But I did it in such a way that everyone assumed he had a seizure. No one will ever know what I did.’

‘You will never clean our blood away in time for your grand opening,’ said Michael quickly, watching the executioner grab Bartholomew’s hair. ‘It will stain your beautiful floorboards.’

‘He has a point,’ said Dunning worriedly. ‘Nothing can be allowed to spoil my ceremony.’

‘I will borrow some rugs from King’s Hall,’ replied Walkelate, his attention on the kindling.

‘Setting the castle alight will ruin the library’s grand opening,’ shouted Michael, desperation in his voice as the mercenary prepared to deliver the fatal blow. ‘All eyes will be on that, and no one will care about your generous donation.’

But Dunning was not listening: he was looking at Walkelate. ‘What are you doing?’

‘He plans to set a fire,’ yelled Michael, toppling sideways and knocking Bartholomew out of the executioner’s grasp with his bulk. ‘Your foundation will be reduced to ashes.’

‘What?’ demanded Dunning. ‘There will be no fires here!’

‘Just a small one,’ said Walkelate calmly. ‘To eliminate evidence of our activities. We cannot have Dame Pelagia poking around and discovering clues we have overlooked. Bartholomew has drawn conclusions from stray metal filings, and it might prove fatal if she does the same.’

‘No!’ cried Dunning. ‘I forbid it!’

But Walkelate had already touched a flame to his sticks, and there was a low roar as they ignited. The resulting blaze was evidently fiercer than he had anticipated, as he flinched away in alarm. Dunning’s jaw dropped in horror.

‘It is the wood oil,’ gasped Bartholomew, fighting back as the executioner tried to manoeuvre him into position again. ‘Kente used buckets of the stuff, and it is highly combustible. Your library will burn to the ground.’

‘No!’ howled Dunning, hauling off his cloak and beginning to beat at the flames. It served to make them burn more ferociously. ‘Bonabes! Help me!’

The heat was so intense that the executioner raised his hand to protect his face. His momentary distraction allowed Bartholomew to lurch forward and punch the pot from Bonabes’s hand. It fell into the fire. With a screech of fury, Bonabes tried to grab it back, but the flames were too powerful.

‘Oh, God!’ shrieked Walkelate, when he saw what had happened. ‘Run!’

‘No one is going anywhere!’ Dunning blocked the door. ‘You will stay here and put out this blaze. The library is my path to immortality, and I am not prepared to lose it.’

But the executioner had had enough, and so had his cronies. They began to advance on the door, swords at the ready, and it was clear that they were not going to let Dunning stop them. Immediately, Langelee surged to his feet and snatched up the blade Ayera had dropped. At the same time, thick, black smoke began to pour from the wildfire pot, and everyone near it started to cough.

‘Damn you!’ cried Bonabes, racing towards Bartholomew with murder in his eyes. ‘You do not know what you have done!’

Langelee leapt forward to deflect the brutal thrust, and the two blades slid down each other with a tearing scream that drew sparks.

‘On the contrary,’ said Dame Pelagia. She was standing behind Dunning, who whipped around in alarm. ‘He knows exactly what he has done.’

Bartholomew slumped in relief as Tulyet and his soldiers poured into the room. There were several brief skirmishes, but the mercenaries knew when they were outmatched, and soon threw down their weapons, claiming they were only hired hands and knew nothing of importance. Then he saw that the pot containing the wildfire was glowing, and his blood ran cold.

‘It is going to explode!’ he shouted urgently. ‘Get away from it! Now!’

But his warning came too late. There was a dull thump, and suddenly burning wildfire was everywhere. It landed mostly on the mercenaries, who had happened to be closest. Then all was confusion, noise and choking smoke. Bartholomew saw Michael’s habit smouldering, and hurried to slash off the smoking material with a knife. He flung it to the far side of the room, where it burst into flames. Michael looked from his ravaged habit to the little inferno in horror.

Bartholomew ran to Ayera, and tried to drag his body to the door, loath to leave him to be incinerated, but the geometrician was heavy and the room was filling with dark, acrid fumes.

‘Leave him,’ gasped Michael, sleeve over his mouth. ‘Outside! Quickly!’

Bartholomew staggered after him, stopping only to haul Langelee away from a skirmish with a defiant mercenary. Tulyet yelled the order for his own men to retreat, and they joined a tight pack who pushed and jostled in their desperation to escape. Coughing hard, his eyes stinging so badly he could barely see, Bartholomew reeled gratefully into the fresh air.

It was a chaotic scene. Several of Tulyet’s soldiers had been injured in the fracas, while the Sheriff himself was hastily divesting himself of armour that smoked ominously. Michael reached out to grab Bartholomew’s arm when the physician turned back towards the door.

‘What are you doing? You cannot go back in there!’

‘Dunning and Walkelate,’ gasped Bartholomew, appalled by the speed with which the fire had taken hold. We cannot leave them in there.’

‘Dunning is dead,’ said Langelee, wiping his dagger on some grass.

‘But Walkelate and the mercenaries!’ Bartholomew tried to struggle free.

‘Most were sprayed with wildfire,’ said Dame Pelagia. ‘Even if you do manage to pull them to safety, all you will do is sentence them to a lingering death. It was on their skin, not their clothes.’

‘But Walkelate is–’

At that moment, a window was flung open, and the architect appeared. He was alight, and his mouth opened in a scream that Bartholomew could not hear over the roaring of the flames.

‘It is too late,’ said Langelee, looking away. ‘The fire will never be extinguished now. Walkelate was a fool to think he could control a blaze with all that oily wood around. And he dared call himself an alchemist!’

‘The castle,’ said Bartholomew urgently. ‘The mercenaries intend to attack it–’

‘I guessed they might try,’ said Tulyet, ‘so I counter-attacked at dawn. The leaders are in my dungeons, and Helbye is rounding up the rest as we speak.’

‘Did Holm tell you to come here?’ asked Bartholomew, sagging in relief.

The Sheriff frowned his bemusement at the question. ‘No. Dame Pelagia chose a better place to eavesdrop than you – one where she would not be taken prisoner by the men she was trying to thwart. She sent word with a fleet-footed beadle.’

‘There will be no fire-arrows now,’ she said, patting Bartholomew’s arm kindly. ‘The good people of Cambridge can enjoy their pageant and never know how close they came to losing their castle.’

‘Thank God!’ breathed Michael. ‘Although our scholars are going to be disappointed when they see what has happened to their library.’

‘Only half of them,’ said Langelee. ‘The rest of us will be glad to see it gone.’

Bartholomew stood for a long time after the others had left, watching the flames consume the building that should have been one of the University’s finest achievements. He wondered whether anyone would ever be brave enough to found another.