Murder by the Book

Chapter 8

It was not far from Bene’t College to Cholles Lane, and it took only a few moments for Bartholomew to run the distance, Cynric at his heels. It was now pitch black, and the streets smelled of warm dust and horse manure, overlain with the dank, rich odour of the river.

The door to Batayl was open, and Bartholomew walked inside to find the hostel deserted. Raised voices told him that everyone was in the tiny garden, which was accessed through a second door at the back of the house. Batayl’s eight students, Browne, Michael and two beadles were crammed into it, all clustered around Coslaye, who lay on the ground.

‘Perhaps you should take your lads inside, Browne,’ Michael was saying. ‘There is no need for them to witness this sad sight.’

‘There is every need,’ Browne snapped. ‘Their Principal has been most wickedly slain by Carmelites, and they should see this vile handiwork.’

‘Enough,’ said Michael warningly. ‘We must assess the evidence before–’

‘Evidence be damned!’ shouted Browne. ‘We all know who did this terrible thing.’

The students howled their support, and it was not easy for Bartholomew to dodge through their waving fists to reach Coslaye. He managed, finally, shoving his new bestiary at Cynric, and inspecting the fallen Principal in the feeble light shed from a lamp held by Pepin.

Coslaye lay on his front, arms thrown out to the sides. He had been dealt a substantial blow from behind, heavy enough to smash his skull. An examination revealed no other suspicious marks, except a bad bruise on his left foot.

‘How did he come by this?’ he asked.

‘It probably happened in Newe Inn, which is always littered with dangerous bits of wood and tools,’ said Browne, his sullen expression making it clear that he considered the injury of far less importance than the one to Coslaye’s head, which had killed him. ‘Walkelate is always inviting us in there, probably in the hope that we will be maimed – in revenge for us opposing his stupid library.’

Bartholomew inspected the foot more closely, and deduced that something sharp had struck it, such as might have happened if a dagger had been lobbed. He stared at the mark. Had Coslaye been among the men who had ambushed him, injured by one of Pelagia’s knives? But why would he want a formula for wildfire? Or had Coslaye been hurt attacking the castle, and Robin had seen him among the raiders? But Coslaye claimed to have been quarrelling with the Carmelites at the time, and so could not have been wielding a sword.

Michael nodded to his beadles, who began to usher the Batayl men back into their hostel. They objected, particularly Browne, but the beadles were used to recalcitrant academics, and soon had them where they wanted them to be.

‘What can you tell me, Matt?’ asked Michael, once they had gone.

‘That Coslaye was hit from behind with something heavy. And that the damage to his foot is several days older.’

‘Did he know his killer? Or is this the work of a stranger?’

Bartholomew regarded him askance. ‘How am I supposed to deduce that?’

‘By the way the body landed?’ suggested Michael. ‘Or the position of the wound? You have drawn such conclusions before, so do not look at me as though I am short of wits.’

‘He is on his front, so he may have been running from a stranger when he was struck. Of course, he could equally well have been trying to escape from a murderous friend. Alternatively, his body could have been moved after he died, to make us think he was fleeing from someone.’

‘That is hardly helpful,’ said Michael reproachfully. ‘Let us discuss his foot, then. What do you make of that?’

‘It looks as though the damage was caused by a pointed implement that struck it with some force, but that was prevented from breaking the skin by his hard-leather shoe.’

‘Did you ever notice Coslaye limping? If we can ascertain when he came by this injury, we may be able to work out how it happened.’

Bartholomew thought hard. ‘I was attacked on Wednesday night, and we met Coslaye the next day when he was quarrelling with the Carmelites, but I do not recall whether he hobbled or not. The next time I saw him, he was lying down – he was ill from bad food. And the time after that he was sitting, reading to his students.’

It told them nothing, and Michael’s expression was unhappy as he led the way inside the hostel, where he asked the Batayl men again what they thought had happened.

‘And do not accuse the Carmelites unless you have solid evidence to prove it,’ he warned.

Browne glowered and folded his arms, petulantly declining to speak unless he could reiterate his firmly held convictions.

‘Perhaps it was suicide,’ suggested Pepin with a Gallic shrug. ‘Coslaye has not been himself since Dunning gave Newe Inn away.’

‘It was not suicide,’ said Bartholomew, trying to gauge the Frenchman’s expression in the flickering light. Had he dispatched his Principal for being a Francophobe? ‘Killing yourself with a blow to the back of the head is virtually impossible.’

‘Virtually impossible,’ pounced Pepin. ‘That means there is a chance that I am right. Yes?’

‘A very small one.’ Bartholomew gave up trying to read Pepin, and turned to Browne. ‘Did you and Coslaye come straight home after visiting Newe Inn earlier this evening?’

‘Coslaye did, but I had business elsewhere.’ Browne scowled when Michael indicated that this was not enough of an answer. ‘All right, I went to watch the Carmelite Priory. But so what? It is not illegal to stare at friaries. I only wish I had stayed longer, because then they could not have sneaked into our home and murdered our Principal!’

There was a growl of agreement from the students, while Bartholomew thought that Browne’s reply did Pepin no favours – if Coslaye had arrived home without Browne, and all the others had been at a sermon in St Mary the Great, it meant that Coslaye and Pepin had been alone together.

‘The Carmelites hate us,’ said Browne, eagerly seizing the opportunity to put his case. ‘And it is obvious what happened: when Coslaye did not immediately agree to Etone’s offer of a truce, one of them came here and murdered him, just as they tried to murder him when they threw that book at the Convocation.’

‘Mon Dieu!’ cried Pepin suddenly, raising the lamp to illuminate what Cynric held. ‘Maybe you are wrong to accuse the White Friars, because here is a big book – one with blood all over it!’

‘It is Bartholomew’s,’ said Browne. ‘I saw him bring it. Is he Coslaye’s murderer, then?’

‘Do not be ridiculous,’ said Michael, raising his hand when several students moved threateningly towards the physician. ‘He is not in the habit of dispatching patients, especially after expending so much effort on making them well.’

‘Surgery!’ spat Browne. ‘Such techniques are contrary to God’s will. Doubtless Satan wanted the soul he should have had at the Convocation, and ordered Bartholomew to put matters right.’

‘If Coslaye’s surgery was against the will of God, then it cannot have been the Devil demanding his death now,’ said Michael scathingly. ‘If you must make slanderous accusations, at least ensure they are logical. However, I think we had better inspect your own books before we go any further.’

Without waiting for Browne’s response, he stalked towards the shelf where Batayl kept its small collection of reading material. When all eyes were on the monk, Cynric promptly shoved the bestiary back at Bartholomew with a moue of distaste.

‘Here is our murder weapon,’ said Michael, withdrawing the tome at the very bottom of the pile. He held it aloft, so the Batayl men could see the dark mess along its spine. ‘The blood is still wet, and you can see hair adhering to it. Coslaye’s.’

‘It is Acton’s Questio Disputata,’ breathed Pepin. ‘The book that almost killed him last time.’

Browne’s face was white with horror. ‘The fact that Coslaye was dispatched with one of our books does not mean that we did it. Anyone could have come in, grabbed the tome and hit him.’

‘Perhaps,’ said Michael flatly. ‘Now answer some questions. Who found him out here?’

‘Browne did,’ replied Pepin, rather quickly. ‘When everyone came back from the sermon, we had something to eat, then sat inside together, waiting for Cynric to come and talk to us about Poitiers. Browne–’

‘Poitiers!’ spat Browne angrily. ‘I am sick of hearing about Poitiers! We won – France is demoralised, she is crippled by debt, her peasants are on the verge of revolt, and our own army continues to ravage her farms and villages. Is this not enough? Must we continue to gloat over the bloody slaughter of her boys, too?’

‘Coslaye was not here,’ Pepin went on, after a brief pause in which everyone looked startled by the outburst. ‘And after a while we became worried, because we all knew how eager he was to hear Cynric. We went to look for him. Browne came out here to check the latrines and there he was …’

‘How long had he been missing?’ Michael demanded.

‘When he returned from Newe Inn, he sent me out to buy some ale to drink while we listened to Cynric,’ replied Pepin. ‘He was not here when I got back, and none of us saw him again until Browne found his corpse.’

‘You have three choices for suspects, Brother,’ said Browne tightly. ‘Namely Bartholomew, a Carmelite or the Devil. It is a pity you did not bother to catch the villain who tried to kill poor Coslaye the first time, because if you had, we might not be mourning him now.’

The next day was cloudy, and the dry heat of the past few days had turned humid. Bartholomew was called before dawn to tend one of the men in the castle, and then was summoned to the hovels on the towpath, where the riverfolk lived. As usual, they were uncommunicative, and it took some time to ascertain exactly what they wanted him to do. Eventually, he managed to evince that several were suffering from stomach pains.

‘Carp,’ said Torvin tersely.

Bartholomew was not surprised. The river was an open sewer, and waste was discharged into it by several friaries, Colleges and hostels, not to mention private houses and two mills. The fish in it were far from healthy, but the riverfolk devoured them anyway, despite his repeated urging to set their nets farther upstream.

‘When did they eat it?’ he asked.

The riverfolk exchanged glances, and he had the feeling that a silent conversation was taking place, one from which he was excluded.

‘Friday,’ replied Torvin eventually.

‘Three days,’ mused Bartholomew. Pangs from tainted food usually eased sooner. He examined all five patients, then sat back perplexed. They looked unwell, with ashen complexions and dark smudges under their eyes, but did not seem to be in unbearable discomfort. He wrote out the remedy he usually dispensed for upset stomachs, then sent a child to the apothecary, remembering to include threepence with the note, because the riverfolk had no money of their own.

‘Perhaps you should avoid fish from the river until after it rains,’ he suggested. ‘Then the rubbish will be washed away, and the water will be cleaner.’

‘They were not from the river,’ said Torvin. ‘They came from Newe Inn’s pond.’

Bartholomew remembered how ill he had felt after swallowing water from the pool. Then he frowned as something occurred to him: Batayl had also suffered from roiling innards, and Browne had admitted to poaching from the library’s grounds – fish that Pepin had added to his stew. Had the stolen carp been responsible for the sickness that had claimed an entire hostel, rather than the dangerously old meat that he had assumed was the culprit?

‘It is not stealing,’ said Torvin, misunderstanding his silence. ‘No one else wants it.’

‘It is University property now,’ said Bartholomew. ‘You do not want to be caught there, so it might be wise to stay away. Besides, I think there is something wrong with the water.’

‘It did stink,’ conceded Torvin.

‘Stink of what?’

‘Corpses,’ replied Torvin darkly. ‘But we were too hungry to care. Will this mean you lose five marks to Surgeon Holm? Because we are caught taking carp?’

‘Not unless you tell him. I certainly will not.’

Amused and conspiratorial smirks flew between the riverfolk, and they all nodded. When the child returned with the remedy, Bartholomew fed it to his patients, then walked home. He had missed church, and the procession was making its way down St Michael’s Lane. Ayera was talking to Langelee at the front of the column, and Bartholomew experienced a twinge of unease when he remembered that he would have to tackle the geometrician that day about Gyseburne’s accusation. With a lurch of alarm, he saw Ayera was limping.

‘Not now,’ said Ayera, when Bartholomew indicated he wanted to talk. ‘I have an appointment, and I am late already. Suttone’s masses are much longer than William’s.’

‘An appointment?’ asked Thelnetham, overhearing. ‘Surely, it is too early for business?’

‘Not when horses are being discussed,’ said Ayera, although his smile was distinctly strained.

‘This is important,’ pressed Bartholomew.

‘So is the horse. I have been negotiating to buy it for weeks now, and would hate to lose it after all my efforts.’

‘Buy it with what?’ asked Bartholomew sceptically. ‘I thought your uncle had left you with nothing.’

Ayera’s smile froze. ‘I hardly think my finances are your affair, and it is ungentlemanly in you to raise such matters. Now, if you will excuse me, I have people to meet.’

He strode away, leaving Bartholomew staring helplessly after him. Now what? Should he follow, to see where Ayera was really going at such a peculiar hour? He took a step up the lane, but someone grabbed his arm and stopped him.

‘No.’ Clippesby’s face was pale, and his eyes had the curiously wild expression that said something was upsetting him. ‘He will prove to be too dangerous an adversary.’

‘What do you mean?’ Bartholomew relented when the Dominican flinched at the agitation in his voice, and spoke more gently. ‘What have you seen, John?’

‘The owls in Bridge Street …’ Clippesby saw Bartholomew’s exasperation and began again. ‘I happened to be in the castle when that raid took place, hiding with two frightened cows. And I saw Ayera. He was mud-splattered, fully armoured, and he was talking to that scribe.’

‘What scribe?’

‘The Carmelite Willelmus, whom Doctor Rougham later spirited away for personal nursing. I did not catch much of the discussion, because they kept their voices low, but I did hear Ayera say that the attack had failed because the raiders had retreated too soon.’

‘So?’ asked Bartholomew, although his stomach churned. ‘He was a soldier once, and is more than qualified to make that sort of assessment.’

‘But what was he doing at the castle at such an hour? Especially wearing armour.’

Bartholomew shrugged, loath to accept the conclusions to which Clippesby’s claims were driving him. ‘Perhaps he has taken a lover outside the town, and he stopped at the castle on his way home when he saw there was trouble.’

‘His lady lives in the Jewry, and he tends to dress nicely for her – his best tabard, not a grubby cloak with a hood that conceals his face. He does not don full battle gear for her, either.’

‘What are you saying?’ demanded Bartholomew, hating what the rational part of his mind was telling him; he still did not want to believe it. ‘That Ayera joined the attack on the castle?’

‘The bats assure me that he will have an excuse that exonerates him completely,’ said Clippesby, taking refuge in his eccentricity with considerable relief. But the guileless smile he tried to force would not come. ‘Unfortunately, the cows do not agree.’

‘We must catch Coslaye’s killer before Thursday, Matt, or Batayl is certain to make trouble at the ceremony,’ said Michael worriedly after breakfast. ‘They will blame the Carmelites, whose feisty novices will react with violence. Or worse, Batayl may accuse one of the library’s supporters – such as you – of the crime. They already know you own a bloodstained book.’

‘I have an alibi for Coslaye’s death,’ objected Bartholomew. ‘I was at Bene’t College.’

‘You think Heltisle will rally to your defence, do you? He has never liked you, and I imagine he will be delighted to see you in trouble.’

‘It would please him,’ acknowledged Bartholomew. ‘However, he will not stand by and see me accused of murder when he knows I am innocent. Besides, he gave me a book, so perhaps he–’

‘A book he wanted out of his College. He was not being generous – he just saw it as a convenient way to avoid giving you cash. But never mind this. We are going to be busy today, not just with Coslaye’s murder, but with the other deaths, too.’

‘And the castle raid,’ said Bartholomew. He took a deep breath and forged on when Michael regarded him questioningly. ‘Because Ayera may be involved. Two witnesses saw him there.’

‘What witnesses?’ asked Michael sceptically.

‘Clippesby and Gyseburne,’ supplied Bartholomew reluctantly. ‘But Gyseburne will deny it if you question him, because he says Ayera frightens him.’

Michael shook his head firmly. ‘Their claims are a nonsense. Langelee told me only last night that Gyseburne had a reputation for secret drinking in York, which led him to all manner of lunatic imaginings, while Clippesby has been odder than usual of late. He announced before church this morning that his rat would be enrolling as a Regent in the Faculty of Canon Law.’

Bartholomew should have been relieved that the accusations against Ayera had been explained away – and he knew for a fact that Gyseburne did enjoy a drink, while Clippesby was currently in one of his more fey phases – but there remained an unpleasantly niggling doubt at the back of his mind, and he knew it would only ease when he had heard Ayera deny the charges himself. He decided to speak to the geometrician as soon as he could corner him alone.

‘How will you move forward on your investigations?’ he asked of Michael, forcing his mind back to the present. ‘You have no new leads to follow.’

‘No,’ agreed Michael. ‘So we must go out and find some. Please note that I am including you in my plans. I cannot manage alone, not without a Junior Proctor. Besides, you did mention a desire to see justice for Northwood, a man you liked and who was your friend.’

Bartholomew said nothing, loath to admit that what he had learned about Northwood since had made him wonder whether he had really known the man at all: his bullying of novices, his inexplicable dealings with exemplars, the possibility that he had blackmailed Vale, and the fact that he had probably been experimenting with lamp fuel on the sly. Of course, to counter all that was his patient tutoring of Julitta and the fact that he had refused to help Tulyet build a weapon. In all, Bartholomew was not sure what to make of Northwood.

Their first stop was the Carmelite Priory, where they learned that everyone had an alibi for Coslaye’s death, because they had all been at a meeting to discuss arrangements for Corpus Christi. Etone had even conducted a roll call, as he had wanted to ensure that every friar, novice and lay-brother was briefed on his responsibilities for the forthcoming festivities. It would have been impossible for anyone to slip out and go a-murdering.

‘Thank God!’ sighed Michael as they left. ‘We had better inform Batayl immediately, to ensure they do not stage a revenge killing.’

‘Yes, but exonerating the Carmelites means you have no good suspects. Personally, I thought Riborowe or Jorz might be responsible. For friars, they are vindictive men.’

‘They are,’ agreed Michael. Then he stopped walking and closed his eyes. ‘Blast! I neglected to ask them to confirm Coslaye’s claim that he was arguing with them over soot when the castle was raided, and now it is too late – they will be at their prayers. I must be losing my touch.’

Bartholomew studied him closely. ‘You seem distracted. Is anything specific worrying you?’

Michael’s smile was wan. ‘Other than the prospect of a riot when the library opens, and the unsolved murders of Vale, Northwood, the Londons, Coslaye and possibly Sawtre and Rolee, too? Well, there is the rumour my beadles reported this morning – that something terrible will happen on Corpus Christi. Several of them have heard it, and the tale seems to have taken root among scholars and townsmen alike.’

‘What sort of “something terrible”?’

‘They were unable to say. Regardless, I am extremely concerned.’

While Michael went to inform Batayl that the Carmelites did not kill Coslaye, Bartholomew returned to College, where he put his students through their paces until the bell sounded for the noonday meal. They escaped with relief when Clippesby approached to report that Langelee had asked William to preside over dinner that day because he was busy elsewhere; the meal would be delayed for a few moments while the Franciscan tried to learn the appropriate grace. Puzzled, as the Master rarely delegated mealtime duties, Bartholomew used the spare time to hunt down Ayera, but the geometrician had not been seen in the College since church.

Uneasy in his mind – he and Michael were the only ones with permission to leave Michaelhouse during teaching hours, so Ayera should have been home – Bartholomew took his place at the high table. As usual, Michael sat on one side of him, while Clippesby was on the other, although the Dominican did not stay there for long: his rat escaped during William’s muddled and largely improvised prayers, and he was asked to leave.

Dinner was a paltry affair of stale bread and a watery stew that tasted powerfully of old fish. It reminded Bartholomew of the concoction that had poisoned Batayl, which then made him think of the riverfolk and his own illness. Had Newe Inn’s water killed Northwood and the others? Cynric was adamant that the pond was evil, and while Bartholomew did not believe such notions, he did know that superstitions sometimes held a grain of truth. Perhaps there was something wrong with the pool, and Cynric was right to be wary of it.

‘I think I was overly ambitious earlier, when I suggested we just go out and unearth a few clues,’ said Michael, dispiritedly. ‘It is easier said than done.’

‘Do you have no new information at all?’ asked Bartholomew. ‘Or no good suspects?’

‘I have hundreds of suspects – that is the problem. Northwood, the London brothers and Vale supported the library, which means half the University bore them malice. Literally. And their sly experiments with lamp fuel mean we must include the medici on the list, too.’

‘Holm is the only one you should seriously consider.’

Michael gazed at him. ‘It is unlike you to take against someone so. What has he done wrong?’

Bartholomew did not want to admit that his antipathy stemmed from the fact that he hated the thought of Holm hurting Julitta. ‘He is an abysmal surgeon,’ he hedged. ‘He was on the side of the French at Poitiers, and he can barely open his mouth without lying. He told Dunning that he was at the castle all Saturday night, but he was not – he slunk off at dusk. And Clippesby says he has a lover.’

‘Really?’ asked Michael keenly. ‘Who is she?’

‘I did not let him say.’ Bartholomew shrugged defensively when Michael rolled his eyes. ‘It was gossip, Brother, and I am no Weasenham.’

‘I suppose Holm is unappealing, but no more so than the rest of your colleagues.’

‘Gyseburne is a decent man,’ objected Bartholomew. ‘He–’

‘He is abnormally fascinated with urine, which you now tell me can be used to make things explode. Coupled with his secret drinking, it means he is a man to watch very carefully.’

‘It does not,’ argued Bartholomew. ‘My colleagues – with the exception of Holm – are only interested in healing.’

‘And in making their fortunes with lamp fuel,’ added Michael dryly. ‘There is no group of men better qualified to kill by stealth, as I have said before.’

‘But that assumes Northwood and the others were experimenting with lamp fuel, and we have no evidence to prove they were. They may have been trying to make ink or paper. There will be money in those commodities, too.’

‘I suppose so,’ conceded Michael reluctantly. ‘And Northwood was a Carmelite, so was in a position to monitor what Riborowe and Jorz were doing.’

‘I cannot see Northwood spying,’ said Bartholomew. ‘And I am not sure what to make of the tales we have been told about him, either. He never gave me the slightest indication that he was eager to amass riches. He was just a man keen to stretch his mind and learn new things.’

‘That is not necessarily a virtue.’ Michael grimaced. ‘I know I sound like William, but we must set some limits on scholarship, or who knows where it might lead? Look at Tynkell, Riborowe, Langelee and Walkelate, who helped to build a ribauldequin for the French wars. Is that any way to use the wits God gave them?’

‘Restrictions will not prevent that sort of activity, Brother. It will only hinder those who are trying to make discoveries for the common good. It is–’

The debate was interrupted by the sudden appearance of Cynric.

‘Come quickly,’ the book-bearer said. ‘Someone has knocked Master Langelee over the head.’

Langelee was sitting disconsolately in Michaelhouse’s kitchen with Agatha hovering protectively behind him. Ayera was there, too, telling her how he had found the Master staggering around dazedly in Cholles Lane. Bartholomew inspected the bump on the back of Langelee’s head, but although it was no doubt uncomfortable, there did not seem to be any serious damage.

‘What were you doing in Cholles Lane?’ asked Michael, watching Langelee wince as Bartholomew applied a cool compress. ‘Visiting a tavern?’

‘I do not frequent taverns during the daylight hours,’ replied Langelee haughtily. ‘I was in Newe Inn’s garden, if you must know. I was curious to see the place where those four scholars died.’

‘Why?’ asked Bartholomew suspiciously.

‘Because it was a peculiar business, and it involved my University,’ replied Langelee tartly. ‘You two do not seem to be making any progress, so I decided to poke about myself.’

‘And did you learn anything?’ asked Michael, ignoring the slight.

Langelee grimaced. ‘No.’

Michael turned to Ayera. ‘And what were you doing in the vicinity? You do not have licence to wander about the town during teaching hours.’

Ayera’s expression was difficult to read. ‘I do not answer to you, Brother.’

‘I gave him permission to be out today,’ explained Langelee. ‘His family have offered to lend him the money to purchase that horse – the one that will benefit the College if we put it to stud – so he went to inspect it. And thank God he happened by! I can well imagine the rumours that would have started if the Master of Michaelhouse had been discovered lying insensible in Newe Inn’s garden.’

‘But Ayera claimed he found you in Cholles Lane,’ said Bartholomew. ‘Not in–’

‘I was stunned, so my memory is foggy,’ interrupted Langelee curtly, while Ayera’s face remained curiously blank. ‘Do not nit-pick, Bartholomew.’

‘Newe Inn’s pond is haunted,’ declared Agatha matter-of-factly, before the physician could press the matter further. ‘Everyone in the town knows it. And on certain very dark nights, strange smells seep out. It is the reek of Hell escaping.’

‘I did not notice any smells,’ said Langelee. ‘But someone came along and hit me very hard. It is fortunate I have a thick skull, because I am sure he meant to kill.’

‘Do you have any idea who the rogue might have been?’ asked Ayera.

‘None at all, but when I find out, I am going to hit him back!’

‘Please do not,’ begged Michael. ‘I do not want another murder to investigate, and there may be an innocent explanation for what happened – one of the workmen may have seen you, and mistook you for a thief. But I shall visit Newe Inn as soon as I have set my students some work. No one strikes the Master of my College and gets away with it.’

Agatha and Langelee followed him out, leaving Bartholomew alone with Ayera. The geometrician went to pour himself a cup of wine, at which point Bartholomew noticed two things: that Ayera’s hands were unsteady and that he was still favouring his left leg. He decided there would not be a better time to ascertain the truth.

‘There has been a report that you were among the men who attacked the castle,’ he said baldly.

Ayera gaped at him. ‘Me? Why would I be involved in such a thing?’

‘I cannot imagine,’ replied Bartholomew. ‘But perhaps it explains why you are wearing half-armour under your academic tabard now, and possibly why you are limping, too.’

Ayera continued to stare. ‘I often wear armour under my tabard. This is a dangerous town, in case you had not noticed. And I hurt my knee just now, helping Langelee back to the College.’

‘May I see it?’ Bartholomew was more than capable of distinguishing between sprains and injuries sustained in armed skirmishes.

‘No, you may not.’ Ayera’s expression was impossible to read. ‘Or are you calling me a liar?’

‘I will apologise if you show me a wrenched knee.’

‘What is going on?’ came a voice from the door. It was Langelee, and Bartholomew wondered how long the Master had been listening. For a large man, he could move with considerable stealth, a skill learned when he had performed dubious deeds for the Archbishop of York.

‘Bartholomew is accusing me of attacking the castle,’ replied Ayera, with a short laugh to tell the Master what he thought of such a ridiculous assertion.

‘Then he will stop it at once,’ said Langelee angrily. ‘There is discord enough in the College with William and Thelnetham sparring all the time. I will not have you two at it, too.’

‘Where lies the problem?’ asked Bartholomew, spreading his hands. ‘I am a physician, and I do not like to see my colleagues suffer. I may be able to ease this painful joint.’

‘I said stop,’ snapped Langelee. ‘And if you persist with these absurd claims, I shall do what other Masters would have done years ago – withdraw permission for you to put patients before your academic duties. That will make you think twice about causing friction in the Fellowship.’

The accusation was wholly unfair, because Bartholomew had never shirked his teaching responsibilities and Langelee knew it. ‘But–’

‘No buts. You enjoy considerable freedom at the moment. Do not make me curtail it.’

Bartholomew watched unhappily as the Master stalked from the kitchen. He half expected Ayera to shoot him a gloating smile as he followed, but the geometrician’s face was oddly impassive. When they had gone, Bartholomew flopped on to a bench and rubbed a hand through his hair. Perhaps he should have been more subtle, and attempted to solicit information without Ayera realising what he was trying to do. But Ayera was not stupid, and would certainly have seen through such tactics. He looked up tiredly when Cynric came to find him.

‘There has been another death, boy,’ Cynric said quietly. ‘In Gonville Hall’s library this time.’

Bartholomew’s stomach lurched. ‘Who?’

‘The messenger did not say, but you had better hurry. The dead do not like to be kept waiting. There are too many angry souls floating around the town already, without adding another.’

It was not far to Gonville and Bartholomew, with Michael puffing at his heels, arrived there in moments. He was relieved when he saw Rougham waiting.

‘This is terribly embarrassing,’ Rougham said, wringing his hands. ‘I hope we can rely on your discretion. We do not want trouble with Bene’t College – they have the ear of the Guild of Corpus Christi, and we cannot afford to lose benefactions over this matter.’

‘What matter?’ gasped Michael. ‘What are you talking about?’

Rougham did not answer, and instead led them to the library. It contained mostly books on law, so Bartholomew had visited it only rarely. Like the libraries in King’s Hall and Bene’t, it was an elegantly appointed chamber, with a profusion of dark polished wood. The books sat in neat lines, each one attached to the wall by a chain to prevent theft. The room was usually busy with students, but it was quiet that day, and empty. Except for one man.

The feisty little scholar called Teversham was lying at a very peculiar angle by one of the lecterns, almost as if his upper half was suspended in thin air. At first, Bartholomew did not understand what he was seeing, but when he crouched next to the Bene’t Fellow, he saw a book-chain wrapped around his neck. He examined the body quickly, noting that there was a triangular indentation in Teversham’s forehead, which matched perfectly the corner of the lectern.

‘The floor is dreadfully uneven,’ said Rougham. ‘We will fix it one day, but at the moment, all our spare cash is going towards the chapel. Teversham must have tripped and struck his head.’

‘And landed on the book-chain?’ asked Michael sceptically. ‘Which strangled him?’

‘It is technically possible,’ said Bartholomew. ‘His head certainly came into contact with the lectern at some point, and he may well have fallen forward and become entangled.’

‘Where, unable to breathe but too dazed to do anything about it, he died,’ finished Rougham. ‘Thank you, Bartholomew. ‘Perhaps you are not such a bad Corpse Examiner after all.’

‘Of course, he might equally well have been shoved into the lectern deliberately, and the chain wrapped around his throat when he was too befuddled to resist,’ added Bartholomew.

Rougham glared. ‘I take it back.’

‘Teversham is not a member of Gonville – he is a Fellow of Bene’t,’ said Michael. ‘So what was he doing here? I surmise he was alone, because otherwise someone would have rescued him.’

‘He came to consult Leycestria’s Qui Bene Praesunt,’ explained Rougham. ‘And he was alone, because I was lecturing on Plato, and ordered all the Gonville scholars to listen to me. Teversham was an old friend, and I thought he could be trusted not to do anything silly. Clearly I was wrong.’

‘Clearly,’ agreed Michael dryly. ‘Have you had any other visitors today? Or seen anyone loitering who should not have been here?’

‘No,’ said Rougham. ‘Yet your questions imply foul play, but this was an accident. Of course it was! We cannot have Bene’t scholars murdered in Gonville! It would cause trouble for certain.’

‘It would,’ acknowledged Michael. ‘However, I do not see how this can be a mishap. It is too … contrived. It is surely a case of unlawful killing.’

‘Not necessarily,’ said Bartholomew. ‘There is no sign of a struggle, and the floor really is uneven. In other words, there is nothing to say one way or the other what really happened.’

Michael rubbed his eyes tiredly. ‘Yet another death with a curious paucity of clues. Either we are dealing with a very sly killer, or we are both losing our touch.’

‘Or there is nothing to find,’ countered Rougham. ‘Not every death in the University is suspicious, Brother, and if you think so, it is time to follow Tynkell’s example, and retire.’

There was no more to be done, so Michael went to break the news to Bene’t. Bartholomew was ordered to wait outside, lest Heltisle took exception to his presence. The physician sat on the edge of a horse trough and pondered Teversham’s curious end. He had not been doing it for long before a shadow fell across him, and he looked up to see his sister.

‘What is happening in your wretched University now, Matt?’ she asked, perching next to him.

‘In what respect?’ asked Bartholomew anxiously.

‘All these deaths. Browne from Batayl has just told me that not only did four men die in the Common Library garden, but that Sawtre and Rolee died in libraries, too. He is braying to everyone that such places are dangerous.’

‘They seem to be, at the moment,’ said Bartholomew, supposing the rumours would really fly when word seeped out about Teversham’s demise.

‘Then please stay out of them,’ begged Edith. ‘I could not bear to lose you.’

When she had gone, Bonabes and Ruth strolled past. Every so often, one would bump against the other, and their hands would touch. They obviously thought they were being discreet, but a number of people noticed and grinned behind their backs. Michael appeared after what felt like an age.

‘They took it badly,’ he said, his plump face pale. Breaking such news was never pleasant. ‘But that is not surprising after Rolee. Two Fellows is a lot to lose in as many days.’

‘If Teversham was murdered, his death raises a whole new set of questions,’ remarked Bartholomew. ‘Because he, unlike the other victims, opposed the Common Library. Violently.’

‘True,’ said Michael. ‘And it means that I am now extremely confused and can no longer see even a glimmer of sense in all that has happened.’

‘Perhaps there is none to see,’ suggested Bartholomew. ‘And they are just a series of random and unconnected events.’

‘You do not really believe that,’ said Michael grimly. ‘And neither do I.’

Bartholomew groaned when Michael said they needed to visit Newe Inn to investigate the assault on Langelee – he was rapidly becoming sick of the place. When they arrived, it was to find Walkelate dealing with parcels of books donated by people who wanted to be recorded as the foundation’s first benefactors. The door to the libri concatenati was closed, and the chamber holding the libri distribuendi was frantically busy. Sawdust was everywhere, and Bartholomew wondered how Walkelate could possibly think it would be ready in three days.

‘Langelee was assaulted?’ Walkelate whispered in horror, when Michael explained why they were there. ‘Here?’

‘In the garden,’ replied Michael. ‘By the pond, apparently, shortly before sext.’

‘Then his assailant chose his time well, because everyone was out then except Kente. The labourers and their apprentices went to a meeting in the Guild Hall about the pageant, while Frevill and I went to the Carmelite scriptorium, to commission labels for our shelves.’

‘But Kente was here?’

‘Yes. He is out at the moment, purchasing gilt, but he will not be long. Will you wait?’

Michael nodded. ‘The attack on our Master is a serious matter, and–’

He turned at the sound of feet on the stairs. It was Dunning, come to inspect progress again. His daughters were with him, with Bonabes behind. Walkelate promptly abandoned Michael, and scurried to greet them, assuring them that the work was much further forward than the untrained eye might think. Dunning did not look convinced.

‘It must be perfect,’ he said, worriedly, ‘or my Guild will think me a fool for wasting my money.’

‘It will be perfect,’ promised Walkelate. ‘But Aristotle is finished at last, and we will mount him on his shelf later today. Have you ever seen more exquisite craftsmanship?’

‘It is fine,’ acknowledged Dunning, running appreciative fingers across the bust. ‘Especially now you have given him less of a nose. I was right to ask you to remodel it, because he looked foreign with the great beak he had originally.’

‘Yet I think you will find he was foreign,’ Michael pointed out, amused. ‘Greek, I believe.’

‘Nonsense,’ declared Dunning dismissively. ‘Aristotle was an Englishman.’

‘The opening ceremony is important to him,’ said Julitta, coming to talk to Bartholomew while Michael regaled her sceptical father with an account of the philosopher’s antecedents. ‘He is beginning to be nervous, lest all does not go according to plan.’

‘Why should it not?’ asked Bartholomew.

‘Well, not every scholar likes the place,’ Julitta pointed out wryly. ‘Brother Michael told me only yesterday that he spends half his life quelling arguments about it.’

‘There was one between Essex Hostel and Bene’t College in our shop this morning,’ added Ruth, who was listening. Bartholomew was not surprised to see Bonabes close behind her. ‘I thought they were going to start hitting each other, but Bonabes managed to evict them first. They slunk away once they were outside, because several beadles were watching.’

‘Father is afraid there will be a spat during the ceremony,’ elaborated Julitta. ‘But I imagine that is less likely if Brother Michael arrests the villain responsible for whatever happened to poor Northwood and the others.’

‘Michael will find the culprit,’ Bartholomew heard himself promise. ‘And I shall help.’

‘Thank you.’ Julitta smiled as she laid a hand on his arm. It felt warm through the material of his shirt, and made his skin tingle. She lowered her voice. ‘I am looking forward to you teaching me how to read once our patients no longer need such time-consuming care. I cannot wait to see my husband’s face! As I said the other night, it will be the most wonderful gift for him.’

‘He will hate it,’ predicted Bonabes, when Julitta had gone to stand with Dunning. ‘Because it means she will be able to monitor his spending of her father’s money.’

Ruth winced, and turned the subject back to the University’s troubles. ‘Did you know that Browne is telling everybody that the London brothers died because God does not approve of libraries? I doubt trouble will be averted if Michael produces God as his villain!’

‘Browne is talking rubbish,’ said Bartholomew. ‘There is a human hand at work here.’

‘I agree,’ said Ruth. ‘And I have learned something that might help you find the culprit. It is about Northwood. Apparently, he used the money from selling the novices’ exemplars to buy materials for his experiments. The apothecary told me.’

‘What kind of materials?’ asked Bartholomew.

‘Red lead and myrrh. Both in very large quantities. And I think I know why, too. Rougham and Holm refused to let him help you invent lamp fuel, and my husband declined his offer to be part of our paper-making trials. So he must have decided to branch out on his own. He was inspired by those scholars from Oxford and their clever inventions, and he wanted to do something similar.’

‘I wish we had included him,’ said Bartholomew ruefully. ‘We might have solved the problem by now, because he had a sharp mind.’

‘Lots of scholars have sharp minds, yet their work proceeds at a snail’s pace,’ said Bonabes disapprovingly. ‘Surely, it cannot be that difficult to make lamp fuel and ink? Perhaps I shall turn my hand to these questions when we have mastered paper. There is a lot of money to be made from them, and I could do with some extra pennies.’

He glanced at Ruth, and Bartholomew was under the distinct impression that any additional income would be used to buy something for her. And her returning smile told him that whatever was purchased would be treasured far more than anything from her husband. When they saw him watching, they flew apart abruptly, Bonabes to inspect Aristotle with exaggerated interest and Ruth to look out of the window.

‘This garden is a sad, forlorn place,’ she said. ‘I have never liked it, and I hate to think of anyone breathing his last here. There is an odd smell, too. Do you think the tales are true, and the pond is home to demons?’

‘Of course not,’ called Bonabes, indicating his ears were still attuned to her voice, even across the room. ‘It is just marsh air, which has a reputation for foul stenches. Some are even poisonous.’

Bartholomew stared at him. Could Northwood and the others have inhaled toxic gases released by the peaty mud at the bottom of the pond? He recalled the beadles claiming they had felt sick when they had disturbed the water, so it was certainly possible. He bowed a brief farewell, and hurried into the garden, aware of Michael puffing behind him, demanding to know where he was going. He did not stop until he reached the pool.

Beadle Meadowman was there, coated with slime as he continued the messy business of dredging through the deeper layers of sediment. He looked hot, tired and cross.

‘I have not found anything, Brother,’ he said. ‘This is a waste of time.’

‘Were you here when Langelee was attacked?’ asked Michael, watching in bafflement as Bartholomew knelt at the water’s edge and leaned down to sniff it.

Meadowman pursed his lips. ‘No – or I would have stopped it.’

‘Then did you see anyone loitering?’ asked Michael, as Bartholomew abandoned the pond and turned his attention to the excavated silt, taking handfuls of the stuff and smelling it carefully.

Meadowman nodded bitterly. ‘Oh, yes. Half the town likes to gawp at the spot where four men died, and opinions are divided as to whether the Devil or God is responsible.’ At last, he could contain himself no longer. ‘What are you doing, Doctor Bartholomew?’

‘I thought the pond or its sediment might contain toxic fumes,’ explained Bartholomew. He saw Michael’s hopeful expression, and shrugged apologetically. ‘But they do not.’

‘Pity,’ muttered Michael, disappointed. ‘That would have been the best solution: death by misadventure and no murder at all.’

While Michael waited for Kente to return, Bartholomew went back to his teaching, hoping it would take his mind off the worries that clamoured at him. His students did not appreciate his zealous attentions, however, and when Cynric arrived with an invitation from Meryfeld, asking him to visit that evening for a resumption of their experiments, they used his momentary distraction to flee.

As there were no pupils to divert him, and the atmosphere in the conclave was icy – Langelee snapped at him when he tried to speak to Ayera – he went to check the wounded soldiers at the castle. Julitta was there, and he lingered far longer than necessary, just to be in her company. When he finally tore himself away, he found Cynric waiting to say that Isnard was unwell. He arrived at the bargeman’s house to find him hunched miserably over a bucket.

‘Have you been eating fish? Perhaps poached from Newe Inn and sold by the riverfolk?’

‘No,’ said Isnard weakly. ‘My malady is much more serious. Holm is trying to poison me.’

Bartholomew regarded him askance. ‘Why would he do that?’

‘For your five marks,’ replied Isnard dolefully. ‘He knows I am innocent, but is unwilling to pay you, so he is trying to kill me instead. He bought me an ale at the King’s Head, and I should have known better than to accept it.’

‘How many other ales did you have?’ asked Bartholomew pointedly.

Isnard waved an airy hand. ‘Not many. Do you think he has done for me, Doctor?’

Bartholomew gave him the remedy he always dispensed for over-indulgence, and watched the colour seep back into the bargeman’s cheeks. When Isnard began to feel better, he started to chat.

‘That armed raid was nasty. It is said by some that the villains are local men, like Ayce of Girton, who bear a grudge against the town and will do anything to harm it. However, there is another rumour that the raiders are strangers – specifically a remnant of the French army, determined to avenge themselves for Poitiers. What do you think?’

‘I doubt the French would pick on Cambridge.’

Isnard sniffed. ‘If you say so. What do you make of the four bodies in Newe Inn? I suspect they are connected to the attack – the victims heard or saw something, and were murdered for their silence. Like Adam, the soldier and the riverman.’

‘I wondered the same. But those three had their throats cut, and there was no obvious cause of death for Northwood and his companions.’

‘So what? There were lots of raiders, and each probably has his own preferred way of killing.’

It was a valid point. ‘Have you learned any more about them? Or have the riverfolk?’

‘Only that they have been slinking into our town regularly after dark – as you found out when we had to rescue you the other night. Obviously, they come to look around.’

‘To look around for what?’

Isnard shrugged. ‘Sheriff Tulyet believes they are smugglers, but I have been thinking about that, and I am sure he is wrong.’

‘Why?’

‘Because I would have seen their boats. No, the raiders are not smugglers, Doctor, and you can tell the Sheriff that I said so.’

By the time Bartholomew arrived at Meryfeld’s house, his medical colleagues had been at the wine. They were not as drunk as they had been when they had thrown together the lethal combination of ingredients to create wildfire, but they were certainly frivolous. Meryfeld laughed a lot anyway, but Gyseburne and Rougham were serious men, and it was disconcerting to see them in boisterously silly spirits. Bartholomew’s heart sank.

‘It is all right,’ said Meryfeld, misinterpreting his concern. ‘We saved you some claret.’

‘Where have you been, Matthew?’ asked Gyseburne conversationally. ‘With a patient?’

‘Isnard,’ replied Bartholomew. ‘He drank too much last night, and has been sick all day.’

Holm sniggered. ‘The man is a terrible sot.’

‘He told me you bought him the offending ale,’ said Bartholomew, rather accusingly.

‘I was in the King’s Head,’ acknowledged Holm. ‘A patient invited me there, and it would have been churlish to refuse, but I did not buy Isnard ale. As everyone in Cambridge knows – except you, it would seem – he is a criminal, and I do not associate with those.’

‘You do if you imbibe at the King’s Head,’ retorted Rougham, holding out his goblet for more wine. ‘No one who frequents that place is innocent in any sense of the word. Except Agatha the laundress. She drinks there, but I would not dare say anything rude about her – she would make garters of my innards.’

‘A lady drinks in a tavern?’ asked Gyseburne disapprovingly. ‘Surely, that is irregular? Or is she a whore?’

Rougham crossed himself. ‘Have a care, Gyseburne! That woman does as she pleases, and she is extremely dangerous.’ He tossed off the contents of his goblet, and indicated he wanted more.

‘She is not that bad,’ said Bartholomew, sipping the wine. It was very good, and when he had finished one cup and was on the second, he, too, felt his anxieties recede. ‘But she cannot cook.’

‘I am an extremely good cook,’ said Holm. ‘My father taught me, and he baked for the King.’

‘The King hires surgeons to prepare his food?’ asked Meryfeld, bemused.

Holm coloured. ‘My father had many talents,’ he hedged.

‘How fare your patients at the castle?’ asked Rougham of Bartholomew. ‘Will any more die?’

‘No, they will all live,’ replied Holm, before Bartholomew could speak. ‘I healed the lot.’

‘So you tell everyone, but it was Matthew who did all the work,’ said Gyseburne, rather acidly.

‘Yes, but he laboured under my direction,’ declared Holm. ‘I am a surgeon, and he is a physician, so how can he have performed these delicate techniques alone? He does not have the skill. Only I do.’

‘You might deceive your fiancée with your bragging lies, but we are not stupid,’ said Gyseburne, coolly. ‘We know the truth.’

‘We do, but it is better for Bartholomew if folk believe that it was Holm who undertook the surgery,’ said Rougham. ‘I say we let him have the credit.’

He had a point, and Bartholomew was certainly prepared to overlook Holm’s conceit in exchange for a quiet life. He nodded his appreciation of Rougham’s suggestion.

‘I can cure stones in the kidneys, too,’ announced Holm, aware that he had lost his colleagues’ approbation and aiming to remedy the matter. ‘I am sure the rest of you cannot.’

‘I have had some success with potions that break them up,’ said Gyseburne. ‘I have detected their remnants in urine after treatment, and patients have claimed a lessening of pain.’

‘I direct a hard punch to a specific area,’ Holm went on, ignoring him. ‘Which smashes the stones into pieces and allows them to pass harmlessly through the urethra.’

Bartholomew cringed. ‘I cannot imagine such a technique would work. It is–’

‘It does – every time. Indeed, I am thinking of going to London when I am married, to punch the stones of the wealthy. I shall make a fortune.’

‘You and Julitta will leave us?’ asked Bartholomew, trying to mask his dismay.

Holm regarded him oddly. ‘We might. I have not decided yet.’

‘Let us go to the garden and begin our experiments,’ said Meryfeld, tiring of the discussion. ‘Time is passing, and I would rather not work in the dark, if it can be avoided.’

His apprentices had already set out a table and various ingredients, along with the large cauldron they used to mix their potions. It bore ominous stains, while parts of the rim had been blown away when trials had not gone according to plan. As usual, Holm, Rougham and Meryfeld sighed impatiently when Bartholomew insisted on measuring each ingredient and recording it in the ledger they had kept since the winter.

‘This is why it is taking so long,’ grumbled Holm. ‘We should just toss in whatever we like.’

‘But then if we do discover a good mixture we will not know what went in it,’ argued Bartholomew, just as he did every time they experimented together.

‘Honey,’ said Meryfeld, approaching with a jar and a wooden spoon. ‘Let us add honey. And if we do not produce decent fuel, I can decant the stuff and sell it as cough syrup.’

‘You cannot let anyone drink this!’ cried Bartholomew, shocked. ‘There is brimstone in it!’

‘Brimstone is not poisonous in small quantities,’ declared Meryfeld. He dipped his spoon in the mixture and took a sip before anyone could stop him. ‘See?’

The others watched him intently, but although he pulled a face to indicate the mixture did not taste pleasant, there was no other reaction.

‘Here is some lye,’ said Rougham, hurling a substantial dose into the basin. Bartholomew threw down the pen and folded his arms in disgust. Rougham had not allowed him to measure it, so the test was over as far as he was concerned. ‘Now you cannot give it to your patients, Meryfeld, because lye is definitely not good for people.’

The calculating expression on Meryfeld’s face suggested he might overlook that fact, and Bartholomew found himself wondering whether the man always declined to reveal what he included in his medicines because half of it was unsuitable for human consumption.

‘And here is some urine,’ said Gyseburne, producing a jar and adding a generous glug. Immediately, something began to fizz, and there was a terrible smell.

‘You have spoiled it!’ cried Meryfeld, hand over his nose. He scowled, and Bartholomew had the distinct impression that Gyseburne had just spared Meryfeld’s clients from being sold a very dangerous “cure”.

There was no more to be done once the mixture was ruined, so the medici left to go home. It was dark, and the streets were unusually deserted; neither townsfolk nor scholars wanted to be out when armed invaders were at large. Gyseburne went north, and Bartholomew found himself walking down Bridge Street with Rougham and Holm. The surgeon was holding forth about his skill with broken limbs, and Rougham was talking about his designs for Gonville’s chapel windows, neither listening to the other, when Bartholomew heard a sound.

‘What was that?’ He cocked his head to listen.

‘The raiders?’ asked Rougham, fearfully. He increased his pace to what was almost a run. ‘We should not linger. It feels dangerous tonight, and we still have some way to go.’

He stopped abruptly when several figures materialised in the darkness ahead of them. He swallowed hard, and Holm whimpered.

‘You may have our purses,’ Rougham called unsteadily. ‘But you must leave us unharmed. We are physicians, on an errand of mercy.’

‘These two are physicians,’ bleated Holm. ‘But I am a surgeon. I heal people, whereas they only dispense expensive remedies and calculate horoscopes.’

‘God’s blood, Holm!’ breathed Rougham, shocked. ‘That was not comradely.’

‘You can go,’ said one of the figures to Holm. ‘We are not interested in you.’

Holm scuttled away without a backward glance, and Bartholomew hoped he would have the sense to summon help. The shadows approached, but he could not tell whether they were the same men who had waylaid him before. He slipped his hand inside his medical bag, fingers curling around the comforting bulk of the childbirth forceps.

‘Tell us the formula for wildfire,’ said one man softly, following a brief scuffle after which Bartholomew and Rougham were pinned against a wall with swords at their throats and the forceps lay on the ground. ‘Refuse, and you die. And do not expect rescue a second time, because it will not be coming.’

‘But we do not know it,’ squawked Rougham. ‘We hurled random ingredients into a–’

‘Then think. We know it involved brimstone, pitch and quicklime, along with a lot of other substances that are irrelevant. But there was one other vital element. What was it?’

‘Rock oil,’ blurted Rougham, desperation in his voice.

‘No!’ cried Bartholomew, horrified. ‘It was not–’

The spokesman hit him with the hilt of his sword, hard enough to knock him to his knees. The next few words were a meaningless buzz as his senses swam.

‘Rock oil was the secret ingredient,’ Rougham went on weakly. ‘It was a gift from a patient, but I could not find a medical application for it, so I tossed it in the pot. That is why we will never recreate wildfire in our quest for lamp fuel. We have no more rock oil.’

‘What is rock oil?’

‘A black, jelly-like substance,’ replied Rougham. ‘It can be–’

‘Rougham, stop!’ gasped Bartholomew, appalled. He had honestly believed that he was the only one who had remembered the rock oil, and was shocked to learn he had been wrong.

‘Wait!’ cried Rougham, when the leader raised his sword to hit Bartholomew again. ‘I can tell you more. It is not found in England – you will have to order it from the Holy Land.’

‘If you are lying–’ began one of the others, taller and heftier than his companions.

‘He is not,’ said the first man. He turned to his cronies. ‘Now kill them.’

‘What?’ shrieked Rougham, shocked. ‘But I told you what you wanted to know!’

‘Yes, and we are grateful. But not grateful enough to spare you.’

Staggering to his feet, Bartholomew fumbled in his bag for one of his surgical knives, determined not to go without a fight. He lashed out at the big man, causing him to howl in pain, but the others moved in quickly and the ‘weapon’ was dashed from his hand. He was groping desperately for another when there was a shout from farther down the street. Tulyet’s soldiers were coming.

The attackers promptly turned and shot down a nearby alley, pausing just long enough to roll a cart across its mouth. By the time Tulyet’s guards had scrambled across it, the ambushers had vanished into the night.

‘You told them about the rock oil, Rougham,’ breathed Bartholomew, making no effort to disguise his dismay. ‘How could you?’

‘Because I did not want to die.’ Rougham’s voice was unsteady, and he leaned heavily against the wall. ‘I was trying to save both our lives.’

‘Dying would have been preferable to revealing such a deadly secret to men like them!’

Rougham rubbed a hand across his eyes. ‘Do not rail at me, Bartholomew. I am not proud of what I did, but I was frightened. And all is not lost, anyway. As you no doubt know, rock oil comes from a wilderness far east of the Mediterranean, not the Holy Land. I misled them rather cleverly.’

‘It will not deter them for long. What have we unleashed on the world? What evil have we done?’

Rougham was silent, and Bartholomew knew there was no point in berating him further. He walked away, to stand alone and bring his temper under control. As he bent to retrieve his forceps and knife, he glimpsed the merest of movements in the shadows. Hands raised, he approached.

‘They have the secret,’ he told Dame Pelagia. ‘You alerted Tulyet’s men too late.’

‘Damn!’ she whispered. ‘I should have known you physicians were too dangerous to leave alive. Did I hear you mention rock oil to Rougham just now? Is that the secret ingredient?’

Bartholomew started to deny it, but faltered into silence as her beady eyes bored into his – he was not good at lying at the best of times, but it was a lost cause with Pelagia.

‘What are we going to do?’ he asked numbly. ‘We cannot let them escape with this knowledge.’

‘No,’ agreed Pelagia. ‘But you have done more than enough tonight. Go home.’

And with that enigmatic remark, she slipped away into the darkness.