A Vein Of Deceit

Book 15: Chronicles of Matthew Bartholomew

by Susanna Gregory

Genres: General Fiction; Historical Fiction; Medieval; Mystery; Amateur Sleuth; Historical Mysteries; Thrillers; Crime Fiction; Historical Thrillers; Medical Thrillers; Suspense

Synopsis

There is something very amiss in the finances of Michaelhouse. Despite a new influx of well-heeled students, there is an acute lack of funds for the upkeep of the buildings, even for decent provisions. It is only when the brother in charge of the account books dies unexpectedly that some sort of explanation is revealed: he has been paying large amounts of money for goods the college itself has never received.

Although shocked by this evidence of fraud, Matthew is more concerned with the disappearance from his herbarium of a quantity of pennyroyal, a preparation known to cause a woman to miscarry, and a pregnant visitor to his sister's household has died from an overdose of pennyroyal. Had she meant to abort her child, or had someone else wanted to ensure she was unable to provide an heir to her husband's wealthy estates?

When Matthew learns that it was her husband who had received Michaelhouse's money for undelivered goods, he begins to search for other connections and exposes a very treacherous vein of deceit.

Release date: December 2, 2010

Publisher: Sphere

Print pages: 480

Sample

August 1357, Haverhill, Suffolk

It was a glorious summer afternoon, with fluffy white clouds flecking an impossibly blue sky, trees whispering softly in a
gentle breeze, and the lazy sound of bees humming among the hedgerows. Cows lowed contentedly in the distance, and the air
was rich with the scent of ripe corn and scythed grass.


There had been a fierce heatwave earlier in the year, followed by torrential rains that had devastated farmland all over the
country. Fortune had smiled on the parish of Haverhill, though: its crops had survived the treacherous weather, and the harvest
was expected to be excellent – its villagers would not go short of bread that winter, and the fat sheep dotting the surrounding
hills indicated they would not be short of meat, either.


But the three men who stood around the little tongue of exposed rock in the middle of the wood saw none of this plenty: their
minds were on another matter entirely.


In the centre of the trio was Henry Elyan, lord of the larger of Haverhill’s two manors. He was a slim, elegant man who took
considerable pride in his appearance – he loved clothes, and spent a lot of money ensuring he was never anything less than
perfectly attired, from his fashionable hat to his stylishly pointed shoes. His weakness for finery exasperated his wife,
who was always reminding him that while Elyan Manor was not poor, it was not exactly wealthy, either, and they had a duty to their tenants to use their profits more wisely than frittering them away on extravagancies.


‘Are you sure, Carbo?’ he asked of the man on his left. ‘You cannot be mistaken?’

Carbo gave one of his peculiar smiles, the kind that made Elyan wonder whether it was wise to place so much trust in the man
– it was common knowledge that he was insane. Of course, Carbo had not always been out of his wits. He had been a highly respected
steward for many years, and his descent into madness had been fairly recent. No one knew why he had so suddenly lost his mind,
although Elyan did not accept the widely held belief that grief for a dead mother had tipped him over the edge. He was sure
there was another explanation, although he could not imagine what it might be.


‘I am not mistaken,’ Carbo said in an oddly singsong voice. ‘It was God who brought me to this place and told me what lies
beneath. And God is never wrong.’


The last of the three men was Elyan’s neighbour, who owned Haverhill’s second, smaller manor. Hugh d’Audley was thin, dark
and pinched, and everything about him suggested meanness and spite. Elyan had never liked him, but money would be needed to
exploit Carbo’s astonishing find, and d’Audley was the only man in the area who might be in a position to lend some. So Elyan
had set aside his natural antipathy towards the fellow and was trying his damnedest to be pleasant.


D’Audley, however, was sighing impatiently, making no attempt to hide the fact that he thought his time was being wasted.
‘Of course Carbo is mistaken! He is deranged, and you are a fool to set stock by anything he says.’


‘Coal is God’s most special gift to the world,’ chanted Carbo, kneeling to rest a reverent hand on the narrow thread of dark rock he had found on his seemingly aimless wanderings. If he was offended by d’Audley’s curt words, he gave
no sign. ‘He calls it black gold. Black gold.’


D’Audley rolled his eyes, and Elyan despised him for his stubborn inability to look past Carbo’s lunacy and see what might
lie beyond. He felt like grabbing the man and shaking some sense into him. Did he not know that coal seams were unheard of
in Suffolk, so finding one in Haverhill was a fabulous piece of luck? And Elyan knew, with every fibre of his being, that
it was going to make him rich – that he would never again have to listen to his wife carping on about the price of fine linen,
or begrudging him the cost of his soft calfskin shoes. The prospect of such unbridled luxury made him giddy, and it was only
with difficulty that he brought his attention back to the present.


‘How do you know about coal and mining so suddenly?’ d’Audley was demanding of Carbo. ‘You have lived in Haverhill all your life, so
how can you possibly claim expertise about minerals?’


‘God told me,’ replied Carbo distantly. ‘He explained about the black gold.’

‘You see?’ said d’Audley, turning rather triumphantly to Elyan. ‘The man is addled!’

Elyan did not reply. The copse in which Carbo had found the lode was dense with brambles and alder, and no one had bothered
to forge a path through the prickly tangle before. There had to be some reason why Carbo had done it, so perhaps God had guided him there. Or was d’Audley right, and grubbing around in the undergrowth was just something madmen did?


‘It is very fine,’ crooned Carbo, ignoring d’Audley as he stroked the rock. ‘The best black gold.’

‘Actually, it is not,’ countered d’Audley. ‘I used the bucketful you gave me last night, and it smoked and spat like an old kettle. Good coal burns quietly and cleanly, but this stuff is rubbish.’


‘Perhaps it was just wet,’ suggested Elyan, refusing to let d’Audley’s sour humour spoil his burgeoning hopes. ‘But regardless,
it will make us wealthy – assuming you want to be part of it, of course? I shall need money to excavate, and if you invest,
you will share the profits.’


‘But I am not convinced there will be profits,’ said d’Audley, looking disparagingly at the thin line of crumbling black rock.


Elyan shrugged, feigning indifference to his neighbour’s scepticism. Unfortunately though, mining was expensive, and he could
not finance such a venture alone; he needed d’Audley’s help.


‘It is your decision,’ he said with studied carelessness. ‘I asked you first because you are my friend, and I wanted you to
share my good fortune. But if you are not interested, I shall approach Luneday instead – he knows a good opportunity when
he sees one.’


He would do nothing of the kind, of course – the lord of neighbouring Withersfield Manor was only interested in pigs, and
was unlikely to spend money on anything else. But d’Audley hated Luneday with a cold, deadly passion, and was blind to reason
where he was concerned.


‘Wait,’ snapped d’Audley, as Elyan started to walk away.

Elyan smothered a smirk before he turned; just as he had predicted, d’Audley was appalled by the notion that Luneday might
benefit from a venture he himself had rejected. ‘Wait for what?’


‘Wait for me to mull it over,’ replied d’Audley sullenly. ‘I cannot make such a decision on the spur of the moment. I need
time to think about it.’


‘Then do not take too long,’ warned Elyan. ‘I want to begin operations as soon as possible.’

They both turned when Carbo started to sing. The ex-steward was lying on top of the seam, treating it to a popular ballad
about love and devotion. D’Audley’s eyebrows shot up, and Elyan took his arm and pulled him away before Carbo’s antics lost
him an investor.


‘My wife is well,’ he said pleasantly, flailing around for a subject with which to distract d’Audley. ‘After twenty years
of marriage, Joan and I had all but given up hope of an heir, yet our baby will be born in December.’


‘Congratulations,’ said d’Audley flatly, and Elyan realised, too late, that this was not the subject to win d’Audley’s good
graces. If he, Elyan, were to die childless, then d’Audley was one of three parties who stood to inherit his estates. A child
would change all that and, unsurprisingly, d’Audley had not greeted the news of Joan’s pregnancy with any great delight.


‘Yet who knows what the future might bring,’ Elyan gabbled on, cursing himself for his thoughtless tongue as he struggled
to make amends. ‘Joan is old to be having a first child, and the midwife says it will be a miracle if she delivers a healthy
son.’


But d’Audley was not listening. He was staring at a nearby holly bush, eyes narrowed. ‘Is that a foot I see poking out from
under those leaves?’


Elyan looked to where he pointed, then strode forward for a better view. Carbo began muttering to himself, rocking back and
forth on his heels as he watched the two Suffolk lordlings with eyes that were too big in his pale, thin face. Elyan reached
the bush and gingerly pulled back the branches, careful not to snag his beautiful russet-coloured tunic. A body lay beneath,
half buried in leaf litter. It was that of a young man, who wore a black tabard over his shirt and hose. A reddish-brown stain
on his chest indicated he had been stabbed or shot with an arrow.


‘That is academic garb,’ said d’Audley, stepping back smartly, and covering his mouth and nose with his sleeve. The weather
was hot, and the corpse was far from fresh. ‘He must belong to one of the Cambridge Colleges – a student, perhaps. What is
he doing here?’


‘I have no idea.’ Elyan was horrified. ‘He cannot have come to spy on my coal, because the only people I have told about it
are my wife, my clerk, my grandmother, Gatekeeper Folyat …’


He trailed off, uncomfortably aware that this was a considerable list – and Folyat was a notorious gossip. Unfortunately,
the gatekeeper had caught him crawling about in Haverhill’s bramble-infested woods and Elyan had felt compelled to offer him
some explanation; he did not want his villagers thinking he was as mad as Carbo.


‘Have you told any scholars about the seam?’ asked d’Audley.

‘No.’ Elyan hesitated. ‘However, my clerk went to Cambridge last week. Perhaps he—’

But d’Audley was not interested in what Elyan’s clerk might have done. ‘This lad has been murdered,’ he declared, glancing
around him uneasily. ‘Stabbed or shot. We had better hide the body before anyone sees it.’


Elyan gaped at him. ‘What? But surely, we should contact the Sheriff, and—’

‘No!’ D’Audley’s voice was loud and harsh. ‘The last time a Sheriff visited Haverhill, he liked it so much that he declined
to leave, and we were obliged to feed him and his retinue for nigh on a month. I am not squandering money like that again,
so we shall shove this boy in the ground and forget we ever set eyes on him.’


‘I will fetch a spade,’ said Elyan, after a moment of silent deliberation. His inclination had been to argue – to do what
the law expected of him – but d’Audley had a point: entertaining Suffolk’s greedy Sheriff had been expensive, and he would rather they spent their resources on excavating what the mine had to offer.


‘And then we had better deal with Carbo,’ said d’Audley, gesturing to where the madman was humming to himself, eyes closed.
‘It is obvious that he is the killer, and he should be locked away before he turns on one of us. We should summon his brother,
and—’


‘It is not obvious at all,’ interrupted Elyan, startled. ‘He may be a lunatic, but there is no harm in him. However, that
sinister Osa Gosse has taken to haunting our parish of late, and he will commit any crime for the right price. It is far more
likely that he killed this young man.’


D’Audley regarded him with an unreadable expression. ‘Perhaps this corpse is a sign – a warning that I should be wary of joining
your venture. So you can bury it: this is your land, so it is your problem, not mine. Watch the mud on your fine clothes, though. It stains.’


And with that, he turned on his heel and stalked away. Elyan watched him go with an expression that verged on the murderous.

October 1357, Cambridge

The scream echoed along Milne Street a second time. Doors were opening, lights flickered under window shutters, and voices
murmured as neighbours were startled awake. Matthew Bartholomew, physician and Doctor of Medicine at the College of Michaelhouse,
broke into a run. Folk were beginning to emerge from their houses, asking each other why Edith Stanmore was making such an
unholy racket in the middle of the night. The noise was coming from her house, was it not?


It was cold for the time of year, and Bartholomew could see his breath pluming in front of him as he sprinted along the road;
it was illuminated by the faint gleam of the lamp his book-bearer, Cynric, was holding. There was rain in the air, too, spiteful
little droplets carried in a bitter wind that stung where they hit. He glanced up at the sky, trying to gauge the hour. Other
than the disturbance caused by the howls, the town was silent, and the velvety blackness indicated it was the darkest part
of the night, perhaps one or two o’clock.


‘What is happening?’ called one of Milne Street’s residents, peering out of his door. It was Robert de Blaston the carpenter;
his wife Yolande was behind him. ‘Who is making that awful noise? Is it your sister? I can see from here that her lamps are
lit.’


Bartholomew sincerely hoped it was not Edith howling in such agony. She was his older sister, who had raised him after the early death of their parents, and he loved her dearly.
Stomach churning, he forced himself to slow down as he negotiated his way past Blaston’s home. The recent addition of twins
to the carpenter’s ever-expanding brood meant they had been forced to move to a larger property, and he was in the process
of renovating it; the road outside was littered with scaffolding, wood and discarded pieces of rope. Bartholomew’s instinct
was to ignore the hazard and race as fast as he could to Edith’s house, but common sense prevailed – he would be no use to
her if he tripped and knocked himself senseless.


‘It is not Edith – it is a woman in labour,’ said Yolande, seeing his stricken expression and hastening to reassure him. Bartholomew
supposed she knew what she was talking about: the twins brought her number of offspring to fourteen. ‘Edith must have taken
in a Frail Sister.’


Bartholomew faltered. A lady named Matilde had coined that particular phrase, as a sympathetic way of referring to Cambridge’s
prostitutes. He had been on the verge of asking Matilde to marry him, but had dallied too long, and she had left the town
more than two years before without ever knowing his intentions. It had been one of the worst days of his life, and even the
expression ‘Frail Sisters’ was enough to make him reflect on all that his hesitancy had caused him to lose. But he came to
his senses sharply when he blundered into some of Blaston’s building paraphernalia and became hopelessly entangled.


‘There are more Frail Sisters than usual,’ Yolande went on, watching her husband try to free him – a task not made any easier
by the physician’s agitated struggles. ‘Summer came too early and spoiled the crops, so a lot of women are forced to earn
money any way they can.’


Another cry shattered the silence of the night. In desperation, Bartholomew pulled a surgical knife from his medical bag and
began to hack at the rope that had wrapped itself around his foot. He could not really see what he was doing, and the carpenter
jerked away in alarm.


‘I cannot imagine why you are in such a hurry,’ Blaston muttered, standing well back. ‘You are not a midwife, so you are not
obliged to attend pregnant—’


‘He is different from the other physicians,’ interrupted Yolande briskly. ‘The Frail Sisters trust him with their personal
ailments, because Matilde said they could.’


Suddenly, Bartholomew was free. He began to run again, aiming for the faint gleam ahead that represented his book-bearer’s
lamp. Cynric, of course, was far too nimble to become enmeshed in the carpenter’s carelessly strewn materials. There were
two more wails before the physician reached Edith’s house, and without bothering to knock, he flung open the door and rushed
inside.


Edith’s husband, Oswald Stanmore, was a wealthy merchant, and his Milne Street property was luxurious. Thick woollen rugs
were scattered on the floor, and fine tapestries hung on the walls. Not for him the stinking tallow candles used by most people;
his were beeswax, and gave off the sweet scent of honey. A number were lit, casting an amber glow around the room. They illuminated
Edith, kneeling next to someone who flailed and moaned. The rugs beneath the patient were soaked in blood; there was far too
much of it, and Bartholomew knew he had been called too late.


‘Thank God you are here, Matt!’ Edith cried when she saw him. Her face was pale and frightened. ‘Mother Coton says she does
not know what else to try.’


Bartholomew’s heart sank. Mother Coton was the town’s best midwife, and if she was stumped for solutions, then he was unlikely to do any better. He knelt next to the writhing
woman and touched her face. It was cold and clammy, and her breathing was shallow. He had been expecting someone younger,
and was surprised to see a woman well into her forties. Her body convulsed as she was seized by another contraction, and the
scream that accompanied it was loud enough to hurt his ears.


‘It is getting worse,’ said Edith in a choked voice. ‘Do something!’


‘She took a potion to rid herself of her child,’ explained Mother Coton. She was a large, competent person, whose thick grey
hair was bundled into a neat coif. ‘Pennyroyal, most likely.’


‘No,’ objected Edith. ‘I am sure she—’

‘I know the symptoms,’ interrupted Mother Coton quietly. ‘I have seen them hundreds of times. She brought this on herself.’

‘But Joan wanted this child,’ cried Edith, distressed. ‘She had all but given up hope of providing her husband with an heir, and was delighted
when she learned she was pregnant.’


Mother Coton declined to argue. She turned to the physician. ‘Can you save her? You snatched Yolande de Blaston from the jaws
of death after I told her family to expect the worst. God knows how – witchcraft, probably. Will you do the same for this
woman?’


‘I cannot,’ said Bartholomew, hating the dismay that immediately flooded into Edith’s face. It upset him so much that he barely
registered why Mother Coton thought he had been successful with Yolande; he was used to people assuming his medical triumphs
owed more to sorcery than book-learning and a long apprenticeship with a talented Arab medicus, but he did not like it, and usually made a point of telling them they were mistaken. ‘I can only ease her passing.’


‘No!’ shouted Edith, beginning to cry. ‘You must help her. Please, Matt!’

Her tears tore at his heart, but she was asking the impossible. He began to drip a concentrated form of poppy juice between
the dying woman’s lips, hoping it would dull the pain and make her last few moments more bearable.


‘I have never seen this lady before,’ said Mother Coton to Edith, while he worked. ‘And I know most of the pregnant women
in Cambridge. Is she a visitor?’


Edith nodded, sobbing. ‘We were childhood friends, although I have not seen her for years – not since she married and left
Cambridge. We met by chance in the Market Square two days ago, and she has been staying with me since. She came to buy ribbons
for the baby clothes she plans to make.’


‘Then I am sorry for your loss,’ mumbled Mother Coton, in the automatic way that suggested these were words uttered on far
too regular a basis.


‘Is Joan’s husband staying here, too?’ Bartholomew asked. ‘If so, we should summon him.’

‘He is lord of Elyan Manor, in Suffolk. But he did not come with her to shop for baby baubles – he stayed home.’ Edith’s hands
flew to her mouth in horror. ‘Oh, Lord! What will Henry say when he learns what has happened? He will be distraught – Joan said this child means a lot to him.’


‘She came alone?’ asked Bartholomew, surprised. Suffolk was a long way away, especially for a woman at such an advanced stage
in her pregnancy.


‘She came with her household priest, who had business with King’s Hall. He is staying at the Brazen George.’ Edith clambered quickly to her feet. ‘I shall send a servant to—’


‘It is too late,’ said Bartholomew, as Joan’s life-beat fluttered into nothing. ‘I am sorry.’

Edith stared at him, and any colour remaining in her face drained away. ‘Then she has been murdered,’ she declared in an unsteady
voice. ‘Do not look at me in that disbelieving way, Matt. I have never been more sure of anything in my life.’


Bartholomew was used to losing patients – he had been a physician for many years, and was the first to admit that the field
of medicine was woefully inadequate, even among the most dedicated and skilled of practitioners – but that did not mean he
found it easy. Even when he did not know the victim, there were grieving friends and kin to comfort, and dealing with death
was the part of his profession he most disliked. He led Edith to a bench, and held her in his arms while she wept.


‘She was my oldest friend,’ she whispered, heartbroken. ‘We spent all day picking ribbons for her baby. Then we ate just after
sunset, and sat laughing about old times. How can she be dead now?’


Bartholomew had no answer. He glanced up, and saw Mother Coton was still with them. He had sent his book-bearer to fetch a
bier, while two maids were swabbing the blood from the floor, so she was not lingering to be helpful. It took him a moment
to realise she was waiting to be paid.


Fees were usually the last thing on his mind on such occasions, and it was a constant source of amazement to him that others
felt differently. He could not pay her himself – Mother Coton’s charges were princely and he was far from rich – so he was
obliged to interrupt Edith’s tearful reminiscences and remind her of her obligations. Fortunately, the need to address practical matters forced Edith
to compose herself. Wiping her eyes, she took a key from a chain around her neck and unlocked a chest.


‘I do not care what your experience tells you, Mother Coton,’ she said, handing over several coins with a defiant glare. ‘Joan
did not take something to end her pregnancy.’


The midwife made no reply, although her expression said she thought Edith would accept her diagnosis in time. Bartholomew
was inclined to agree: Joan’s symptoms matched those of an attempt to abort. Of course, Edith’s testimony suggested Joan was
happy with the prospect of motherhood, but it was not unknown for women to change their minds, and Joan was old for a first
pregnancy – perhaps she had not wanted to risk dying in childbirth.


One of the maids picked up Joan’s cloak, intending to lay it over the body. As she did so, a little pottery jar dropped out.
Had it landed on the flagstones, it would have shattered, but it fell on a rug, then rolled under the bench. Bartholomew bent
to retrieve it.


‘A tincture containing pennyroyal,’ he said, after removing the stopper and sniffing the contents. He poured a little into
his hand, then wiped it off on his leggings. ‘Not the herb, but the oil, which can be distilled by steaming. It is highly
toxic.’


Mother Coton nodded her satisfaction at being right. ‘It is the plant of choice for expelling an unwanted child.’

‘Then someone gave it to her,’ said Edith firmly. ‘She did not take it of her own volition.’

Mother Coton looked as if she might argue, but then raised her shoulders in a shrug, and when she spoke, her voice was kinder
than it had been. ‘You should rest now, Mistress Stanmore. It has been a long night, and things will look different in the
morning.’


One of the maids escorted her out, while the other took away the blood-soaked rugs and finished cleaning the floor. She was
efficient, and it was not long before all evidence of traumatic death had been eradicated – with the exception of the cloak-covered
corpse. Edith stared unhappily at it.


‘Where is Oswald?’ Bartholomew asked, realising for the first time that his brother-in-law had not made an appearance. Stanmore
was solicitous of Edith, and although theirs had been an arranged marriage, they were touchingly devoted to each other.


‘Lincolnshire. He told you at least twice that he was going, and asked you to look after me.’

‘Did he?’ Bartholomew was appalled to find he could not remember. Term had just started, and he had been saddled with more
students than he could properly manage. He was struggling to cope. Of course, that was no excuse for failing in his obligations
to his family.


‘Yes,’ she replied. ‘Otherwise he would have ordered me to stay at our manor in Trumpington, where he thinks isolation will
keep me safe. He does not like the notion of me being in town alone.’


‘Then I have let him down,’ said Bartholomew guiltily. ‘I have barely seen you since term began.’

She shot him a wan smile. ‘It was what I was hoping. I do not want a protector breathing down my neck, and the servants are
here. So are the apprentices. And then Joan came …’


‘You say she was visiting Cambridge?’ asked Bartholomew, sensing her need to talk.

Edith nodded through fresh tears. ‘She was my closest friend when we were children. Do you not remember her? Our favourite
game was to dress you and the dog up like twins.’


Bartholomew raised his eyebrows. ‘It seems to have slipped my mind.’

‘She has not changed.’ Edith’s smile was distant. ‘We still laugh at the same things, and she was so happy to be giving her
husband an heir. She thought she was too old to conceive.’


Bartholomew would have thought so, too. ‘It is unusual to be pregnant for the first time at her age.’

Edith’s thoughts were miles away, and she did not hear him. ‘She joked with your colleague Wynewyk in the Market Square –
she persuaded him to choose the colour of the ribbon she was buying, and their witty banter attracted quite a crowd. They
were flirting, making people laugh.’


Bartholomew regarded her askance. ‘I sincerely doubt it! Wynewyk prefers to flirt with men.’

‘Well, he was doing it with Joan today,’ said Edith stiffly. ‘They were very funny.’

Bartholomew did not want to argue with her. ‘Why was she staying with you, if you had not met for so many years?’

‘Her husband does business with King’s Hall, and sent his priest there to draft some agreements. She decided to travel with
him, to shop for baby trinkets. She was going to lodge in the Brazen George, but when we met by chance in the Market Square
I decided she would be more comfortable here, with me. But someone still managed to kill her …’


‘No one killed her,’ said Bartholomew gently. ‘And if you say she wanted this child, then we must assume her death was an
accident – she took the pennyroyal by mistake. Her pregnancy was obviously well along, so no apothecary would have prescribed
it. She must have bought that tincture herself, without realising it would harm her.’


Edith sniffed, then nodded, although he could see she was not convinced. He supposed she did not have the energy to debate
the matter; it was very late, and he knew from the amount of spilled blood that the battle to save Joan had raged for some
time before he had been summoned.


‘We ate supper and talked a while,’ said Edith unhappily. ‘Then she went to bed, while I stayed up, sewing Oswald a new shirt.
Not long after, she stumbled into this room, and there was blood … I wanted to call you, but she said she needed a midwife.
Perhaps I should have ignored her wishes …’


‘Mother Coton knows what she is doing. You did the right thing.’

Edith sniffed again, then looked up when there was a soft tap and the maid answered the door. ‘Here is Cynric, and he has
brought three of your pupils to carry Joan away. He is a thoughtful soul.’


Bartholomew’s book-bearer had been with him since he was an undergraduate, and was more friend than ser