'What's wrong with it?'

'Blowed if I know.' Mustrum Ridcully prodded the thing with a stick. A long stick. 'Are you okay, what are you doing man?'

Ponder Stibbons had climbed onto the first level of the decorative sculpture "A Pile of Matches", a delicate and dangerous feat in itself as the carving was not only made of wood but had working phosphorus heads, adding the exciting possibility of ignition to the list of life-threatening outcomes.

The previously unknown Bergholt Stuttley Johnson design had recently been unearthed by the Ankh-Morpork and Sto Plains Hygienic Railway engineers in a remote valley, which also contained some interesting temporal anomalies[*]. The wizards of Unseen University had agreed to relocate the sculpture for as many rides as they wanted on the railway, along with free ice creams when they arrived in Quirm. 'I thought I might be able to see what it was doing,' he called down.

'It's perfectly obvious that it isn't doing anything! Get down from there, if you fall off you'll do yourself a Geography!'

'Talking of which, where is the funny looking fellow with the questionable taste in millinery?' said the Head of Unforseen Circumstances, 'He'll know. It belongs to him, doesn't it?' Huck, as Dr Hix had swiftly become known, was new to the academic legions of UU and therefore ignored with the utmost contempt, as he hadn't yet had to sit down for his inaugural one-to-one with Ridcully, or "The Vexation", as it was termed by anyone who had been subjected to the horrifying ordeal.

The Bursar looked at Dr Hix with a peculiar expression on his face. 'When's his next dose due, Runes?' whispered Ridcully. The Lecturer in Recent Runes looked slightly terrified at being interrupted from the thorough inspection he was carrying out of his own sandals, to give the impression he was deep in contemplation and shouldn't be disturbed.

The Senior Wrangler decided to enter the fray, 'I think it looks a bit sad, should we try feeding it something? What does it eat?'

'Mostly people who upset it,' Ridcully said. The Wrangler took a couple of paces backwards and stood, nonchalantly, behind the Chair of Indefinite Studies who, although not perhaps as appetising would at least make for more of a mouthful.

Stibbons was now standing on the fifth match, he turned and steadied himself, then girded his loins to look the 20 feet down to the scene below. Raising his voice he started talking, then stopped and raised it some more to compete against the seven wizards, the auditory equivalent of a quorum of howler monkeys. "I think I've found something.' A couple of the addressees actually looked vaguely upwards to see what the noise was, after some further arguing and pointing in various directions the rest of them turned their heads towards him. 'I say, I've discovered something that may or may not help our investigations."

A number of whispers, of the piercing variety, made their way up through the thinner air. Phrases like "what's he shouting about?", "why's he telling us?" or "is it nearly time for Third Breakfast yet?" were amongst them. Ponder reached into his robes and pulled out his newly purchased Chriek's Instantaneous Iconograph, he shook it about a bit to wake the imp then pressed the button to capture the scene below. A small square of paper rolled out of an opening at the front, accompanied by some choice words from within about Ponder's framing of the scene.

Deciding to use the direct, if somewhat more mentally strenuous, method of getting to the ground he spread his hands and became the causal nexus in a consequential pivot between himself and a roughly Ponder Stibbons-sized rock residing in the gardens[†], as a result of which, the rock catapulted up into the air to compensate for the mass of a bespectacled wizard dropping slowly and gently to the ground.

The Archchancellor snatched the iconograph from Stibbons's hand and squinted at the image. Ponder reached out and turned the picture over so it was the right way up, then pointed at the tracks on the grass. 'Footprints?' Ridcully asked.

'Ostensibly!' Ponder never liked being too specific when dealing with the Archchancellor's single-minded lateral thinking approach.

The wizards aggregated, like a well fed continental drift, behind them to see what was going on. The Senior Wrangler's eyes scanned back and forth between the picture and the patch of grass which it illustrated. 'There's nothing there, your imp must be broken.'

The Lecturer in Recent Runes made a tutting sound, 'Look closer man, they're octarine. Whoever or whatever made those was emitting thaums like it's going out of fashion.'

Ridcully licked his finger and looked at it carefully to gauge the strength of the magic field, but Stibbons, being more practical, reached into his robe and pulled out his thaumometer, recently upgraded to indicate the direction, as well as the strength of the magic. He held the device in front of him, much as you might hold an unidentified ticking parcel, and pointed, saying 'This way.'

The procession of thaumaturgists moved away from the motionless travel accessory which had initially attracted their attention. They shuffled along behind the Head of Inadvisably Applied Magic, trying to make it look like they wanted to be first in line, but carefully pacing themselves to head up the rear, in case there was any actual excitement. The unconventional conga line threaded between bushes, around statues and then drew up short at one of the University's outside walls, where another hastily developed iconograph showed the phantom plantar profiles appearing to proceed directly through a persuasively solid wall.

'Well that solves that mystery then!' The Chair of Indefinite Studies turned to leave, but was persuasively rotated and made to admit that, perhaps, the apparent lack of any further progress by the invisible footprints didn't mean the investigation was over.

Ridcully, who was more observant than the other wizards could bring themselves to admit, pointed out that there was a faint shimmering circle on the wall. He walked up to it and looked more closely, the top of the ring was at head height and the rock behind the, for want of a better word, hole, seemed slightly out of focus. Mustrum licked his finger again and reached out towards the surface. His digit started to glow with a greenish-yellow purple light. As he got closer to the wall the intensity of the light increased until his index finger shone like a psychedelic lighthouse.

The other senior wizards covered various orifices, expecting a gaudy explosion of some sort, but as Ridcully's finger breached the surface there was an ominous lack of action. He pushed further forward and his hand disappeared from view. 'Well it's definitely a portal of some sort. Can you find out where it goes, Stibbons?'

'Um, yes sir.' He walked up to the portal, reached his arms through and brought them back, still clutching the iconograph, which was perfunctorily rolling out a new picture.

After waiting for the appropriate amount of time for the paint to dry, while being subjected to the Senior Wrangler's list of dangerous things that could be on the other side, Ponder held the picture up. Necks were craned, eyes were screwed up, the Lecturer in Recent Runes, never too proud to blatantly state the obvious, stated 'It's a field!'

The picture showed a pleasant green hillside, with trees and bushes spotted across it like a mild rash. A dark stained wooden fence split the image in two, in the foreground there was a hazy mess of last season's nature, spindly twigs pointed every which way, some reaching as high as the top of the fence. 'Looks a bit like Skund!' said the Chair of Indefinite Studies.

There was a sudden, violent flash of octarine from the box hanging around Ponder's neck. A couple of the wizards, already on edge, almost lost control of their lower level faculties.

Stibbons nearly fell through the gateway, but instead careered sideways and cracked his head on the brickwork. After regaining his composure, he opened the little hatch on the back of the iconograph and peered inside. There were colourful scorch marks on every wall of the little room, partly through the expiration of the imp inhabitant, partly from the pots of paint caught up in the explosion. 'What happened?' asked the Archchancellor.

Ponder looked sadly at his perished picture box, then said, 'I have an idea, does anyone have anything magical?' After some heated discussions, Huck held out a hand in which he bore a small vial of liquid which glowed rather pleasingly. 'That's a Temporal Agitator[‡] isn't it?' The Head of Unforseen Circumstances nodded curtly to Stibbons looking, with almost uncanny foresight, a bit upset that he might not get the chance to enjoy a second Third Breakfast today.

Ponder pulled some tongs from a concealed pocket, then gripped the small flask and thrust it through the gateway. Upon retrieving it he started counting under his breath and had reached the number 57, when the glowing liquid seemed to suffer a sudden attack of reality, lost its octarine glow and went transparent, black hairline cracks appeared in the container. He carefully snapped the top off the phial and sniffed it. 'Water!'

The Head of Unforseen Circumstances looked morosely at the floor and muttered a quiet oath which, due to the unusually strong magical field surrounding the portal, manifested itself as a small hippopotamus wearing a bowler hat and carrying a rolled up newspaper under its arm. After a couple of moments of confusion, the hippo unfolded the paper, doffed his hat and wandered off towards the Wizards' Pleasaunce, reading about a cabbage looper outbreak on the Sto Plains.

The Chair of Indefinite Studies unexpectedly gave a sharp and slightly effeminate shriek from the rear of the gathering, the other wizards moved away in self-defence, before turning to see what was happening. Looking extremely morose, the Luggage was standing behind him and staring or to be more accurate pointing its keyhole forlornly at the swirling patterns on the wall. The Chair edged slowly forward until he was out of snapping distance then turned to regard the trunk. 'Well at least the thing is mobile again. What's it after?' Ridcully asked.

Ponder Stibbons pointed towards the magical doorway, 'My suspicion would be, there's something on the other side that it wants.' When the Archchancellor raised his eyebrows, preparing to ask why it didn't just go through, Ponder continued, 'I think what we are looking at here is a gateway to another place, but a place where magic doesn't, or in fact can't exist. If anything magical travels through that portal it probably expires after about a minute, Sapient Pearwood included.

The eight mages looked down at the pitiful travel accessory, which was radiating a deep feeling of loss from every knothole. Ridcully made a decision, 'Well we have to do something about it, the thing is like part of the furniture round here.' He glared at the Senior Wrangler who was about to point out that it was, literally, a part of the furniture. 'It's almost a staff member. I'll be back in a minute.' And he strode away.'

Small talk being low on the list of 100 hundred things wizards are good at, there was an interminable silence, interceded by the occasional giggle from the Bursar. As the hush became more intense Dr Hix made the fatal mistake of asking if anyone had seen last night's foot-the-ball game between Borogravia and Genua. It didn't take long for the conversation to escalate into pandemonium, with the Senior Wrangler pointing out that the Lecturer in Recent Runes wouldn't know a foul if he was served it for Early Breakfast.

The discussion was abruptly curtailed when a stout arrow took off the Bursar's hat and pinned it neatly to a nearby Golden Disagreeable, which was so surprised it dropped an apple and completely lost its philosophical train of thought about a new branch of religion[§].

The Archchancellor grimaced at the effort of reloading his crossbow, 'If we can't take magic through then we'll have to do with artillery! Who's coming with me?' There were a series of less than positive noises from the congregation, who would all much rather be in their studies wearing carpet slippers, with a nice warm milky drink and a good grimoire, than gallivanting to uncharted who-knew-where to make a suitcase feel a bit more like itself! 'Who's going first?'

As Ridcully was pushing the Bursar headlong towards the iridescent circle, a few things happened within a very short space of time. The Luggage suddenly started jumping up and down, which rather upset the Chair of Indefinite Studies, who hadn't quite got over the previous excitement of being jolted by such a dangerous item of personal travelling equipment, this made him give another short strident yell. The Chair's shouting surprised the Archchancellor who accidentally loosed another quarrel which sailed, uninterrupted this time, towards the portal. Last, but by no means least, the spinning effervescing lights on the wall blazed momentarily before they were breached by a thick rectangular piece of wood, which the arrow partially perforated before quivering to a halt.

The wizards looked on dumbfounded at the wooden panel, which had paused briefly in its approach after being hit by the swift and lethal wooden projectile. The board also emanated a strangled noise which sounded a bit like "gwaaark".

The timber was eventually lowered to reveal a pair of wild eyes, still staring at the pointy tip of the missile, which was a hairs breadth from the concave chest, attached to the permanently disinclined shoulders it dangled below. 'Urrnk!' was the next thing that the owner of the eyes managed to vocalise, before collecting their thoughts for another go. 'I'm glad I took precautions, at least I know where I am!'

The hardboard was dropped to reveal a man in an unusual outfit. The materials covering the unimposing apparition were dark, with tubular legs that were actually leg shaped, as opposed to the more usual and freedom enhancing robes worn by the wizards. The top was a single piece of thin black fabric with a picture of a wizard holding a long staff[**] and a lamp. Some unrecognisable runes were shown underneath two words emblazoned across the front, 'What's a Led Zeppelin?' asked the Lecturer in Recent Runes, his question was disregarded, as per the agreed best practice amongst other senior faculty members.

The Luggage extended its legs and bounded over, nearly knocking the outlandishly dressed newcomer over, then opened its lid to reveal a neatly ironed pile of clothing. The man rummaged around in the case and eventually came up for air clutching what must once have been a hat. He shook it out to try and give it the shape it had never quite possessed, then reverently lowered it onto his head to make sure everyone knew he was a "Wizzard".

Ponder Stibbons, who was always good with names, was the first to speak. 'It's Rincewind, isn't it?'

The Chair of Indefinite Studies nodded his head as some long disused neurons started firing, 'the Professor of Cruel and Unusual Geography. We were just talking about you man, where have you been? Your Luggage was pining for you, although it might have been pearing!'

Having recovered from almost being pierced, Rincewind seemed to remember what he was doing and composed his features into an agonised half-smile. 'It's very important that you don't go through the gateway,' he pointed at the portal, which seemed to have changed it's ever swirling patterns since his arrival.

'Why?' Asked the Head of Unforeseen Circumstances, who should have known better, 'Is it dangerous, will it unleash unimaginable horrors from the Dungeon Dimensions, is it an alternative reality of the trouser legs of time where you can't get a decent pint?'

Ridcully waved Huck into silence. Although he was as emotionally sensitive as a rhinoceros with horn ache he was still aware that Rincewind needed some time. 'Let's go to my office, someone get the man a drink.'

As with Senior Academics the multiverse over, Ridcully's office was a cornucopia of disparate and seemingly provocative trophies from a lifetime of reading, hunting, fishing and, possibly, genetic engineering. Rincewind had been offered a seat facing the Archchancellor, the other wizards crowded in behind him and tried, unsuccessfully, to ignore the fact that there wasn't enough space for their expansive forms to fit comfortably in the room.

A pint of Turbot's Really Odd ale was standing in the only space on the repurposed snooker table which wasn't already covered with paperwork, books, bones, octograms or crudely drawn pictures of other staff members in amusing or insulting situations. Rincewind waited patiently as the hubbub diminished and watched the sediment slowly sink through the murky fluid.

Silence finally prevailed. 'Do any of you remember Roundworld?' Wizards, while experts at the mental gymnastics required to hold spells, runes, symbols and the multitudinous mealtimes that such arduous cerebral exercise warrants, are still notoriously bad at actually remembering the fine details of their own lives. Most shook their heads while a couple muttered some words about monkeys, meteorites and some men named Darwin and Shake-something, some kind of a weapon wasn't it?

'It turns out that when we created the Roundworld universe we somehow inextricably tied ourselves to it, but the link isn't one-way. I've been doing some quite extensive studies and it turns out they don't just get their developments from us, it works the other way around too. They had a version of the clacks long before we did and there are carriages that work by burning oil to release energy.'

The Senior Wrangler thought about this for a moment before asking, 'Doesn't that upset the horses?'

'They don't use horses, the energy from the combustion makes them move. In fact there's no magic at all, the whole place runs on something called science. They seem to make discoveries by experiment and accident.'

'I once discovered that it makes a terrible mess when you try to catch a swamp dragon using a slingshot.' The Archchancellor said, remembering how long it took to remove the smell.

Rincewind continued, unabashed, 'The door to Roundworld, I call it the "Round Door", actually came into existence a year ago, I discovered it because I fell through when I was coming back from the, erm…Temple of Small Gods, one night…'

The Chair of Indefinite Studies mouthed, 'He means The Drum.'

'…the first thing I discovered was that the time dilation effects we observed when we went through before weren't quite as pronounced. Time was passing faster there, but not at the level of civilisations.'

Ponder Stibbons had been thinking about the gateway for some time and a question had been scrabbling at his senses, 'Why haven't we seen the portal before, I've walked past that part of the wall hundreds of times?'

Rincewind made the face that everyone makes when taking their first sip of the day from a pint of real ale, halfway between a smile and trapping your finger under a horse. He tried to put the stein back on the desk but was defeated by the tidal wave of interesting items, which had slowly flooded over the wanton gap left by the mugs removal, he gave up. 'It doesn't always seem to exist, it also moves around! After I fell in, I seemed to have some kind of connection to the thing and it followed me. I'd be shopping and it'd be there near the vegetable stall, or I'd be getting ready for bed and it'd be behind the curtains. So eventually I decided I'd better go through again and have a proper look around.'

The other wizards scratched their heads, as he continued. 'Anyway, the first time I went I was trying to keep a low profile, which is difficult when you're wearing a foot-long pointy hat, but was almost immediately flattened by a car, that's one of their horseless carriages. The driver stopped and took me home, offered me a drink and asked why I was wearing a dress. After I explained that it was a robe, I told him where I was from and what I was doing there and he started asking me questions and writing things down in a notebook. I think the act of nearly running me down completed the link and he became the focus for the Round Door on the other side.'

The Senior Wrangler asked, 'What did you tell him about?'

'Oh, you know, the almost end of the world and when I had to read the 7a[††] Great Spells from the Octavo.' Everyone turned to look at the Luggage, which had become the final resting place for the only copy of the Creator's misplaced cosmos manufacturing manual. The Luggage had the decency to look embarrassed. 'He said he was going to write a book about it. As I understand, it sold quite a lot of copies!'

'The next time the Round Door appeared was not long after that poor sourceror boy had encouraged us to destroy the fabric of reality. Funnily enough I told my Roundworld friend about that and he wrote another book. That did pretty well too!'

'The portal has been taking me back every so often, usually when there was something interesting to talk about. Then it reappeared a few months ago, things had been quiet round here and I was surprised when I saw it, but when I went through I knew something was wrong.' Rincewind took another mouthful of ale and looked dejectedly at the paperwork avalanche, which was making slow but steady progress towards the Hubwards edge of the desk, where it was hoping to make a break for freedom and the slopes of Cori Celesti.

Ponder Stibbons cleared his throat before asking, 'What was the problem?'

In the grand tradition of Ankh Morpork street theatre, the assembly listened with bated breath. 'Usually when I went through he'd be there waiting for me. He seemed to know when I was going to turn up each time. But this time I was alone, at least for a minute or two. Then I heard someone falling over in the mud nearby, it turned out to be a nice young man called Rob, he invited me for a cup of tea and told me a story.'

This man, Rob, had been employed by my Roundworld associate to help him, since he had found out he had PCA,' the wizards' countenances projected enlightenment like a black hole radiates light, 'which stands for Posterior Cortical Atrophy.' This expansion didn't help.

The Lecturer in Recent Runes turned to the Chair of Indefinite Studies and whispered at an ear shattering volume, 'Sounds a bit like that unfortunate incident you had in your bathroom last month!'

Rincewind managed to ignore the interruption, 'it's a condition that makes the outer layer at the back of your brain degenerate and affects your cognitive skills. It means you have difficulty recognising shapes, objects or writing.' Everyone turned to regard the Bursar, who was staring vacantly at the Archchancellor's obligatory stuffed alligator, which was staring back at him with a look of vague panic on its permanently ingrained features. 'It doesn't send you Bursar though, it just slowly eats away at your ability to recognise things.'

The room had gone very quiet. No one made a sound apart from the Wizzard at the eye of their attention hurricane. 'You start off by losing your keys and eventually you can't find your house. Rob explained the whole thing to me and told me that there was no cure, it would only get worse. Since then the Round Door has taken me back twice more, he's living in Wiltshire now, which is a bit like Überwald, but with more pigs!'

'I could see him deteriorating. I don't think he told other people but he figured that because I was from forn parts I was a good pair of ears,' everyone stared at the sides of Rincewind's head to see if this were true, 'He told me about the disease, the effects, the frustration, the lack of control, the depression and the anger. But because he had his assistant, Rob, he was getting along a lot better than most do.'

'After I returned that time, I wasn't sure if I'd be going back again. So I was quite surprised to find the portal embedded in the wall near Scholar's Entry, when I was on my way to breakfast this morning.' The digestive system belonging to the Chair of Indefinite Studies made a pitiful gurgling sound at the mention of its previous meal, which seemed rather distant now it came to ruminate on the subject. He quietly undertook the not insignificant task of rubbing his stomach.

'What happened then, man?' The Archchancellor would have moved to the edge of his chair if he hadn't been there already, in deference to the odds and ends of everyday and never-should-have-been oddments stacked up and occasionally clinging unpleasantly to the backrest.

Rincewind gave a heavy sigh, then took a preparatory breath. 'The Roundworld side of the gateway was, unusually, inside a building. But it was a building I knew. I think the Round Door and L-Space had collided, so I appeared inside his library, which is a wonderful thing to behold, even if you've been the deputy ape at Unseen University. The house was strangely quiet though. I eventually found out why. My Roundworld friend was in bed, surrounded by his family, with his cat perched near his feet.'

'He had contracted an illness and that, along with the PCA, had pushed his body to the limit. His wife, Lyn, invited me in and asked me to stay with them,' a tear welled up and rolled without drama through Rincewind's meagre covering of facial hair. 'He died while I was there, in his bed, with the people who loved him. And now he's gone. There's no coming back, or challenging Death to a game of chess, no ghosts, nothing but the end of life on Roundworld. Which is actually better, when you come to think about it!'

A number of crinkly handkerchiefs had been discovered in pockets and were dabbing at long disused tear ducts. Ridcully, who could be bought a drink, a starter and main course, then taken to a seedy club on the outskirts of town for an evening of drinking strangely coloured and amusingly named alcoholic beverages by an emotion, before he recognised it, was looking into the middle distance with misty eyes, 'So, what now?' he asked, primarily so the room wasn't suffused with silence.

'I have a suspicion.' Rincewind got up unexpectedly and headed out the door. After a confused moment the rest of them followed him, soon ending up, once more, in front of the Round Door. 'I'd stand back if I were you,' he said as the Wizards crowded round. The swirling colours disappeared, leaving a circular hole into another reality, the same landscape, in fact, that Stibbons had taken a picture of an eternity ago.

'I think that my Roundworld friend's remarkable, magical and white-hot mind was what opened up the portal in the first place, without him I don't think it can exist.' He gestured for the Luggage and found the small glass globe which, quite disregarding the normal laws of quantum mechanics, contained the planet and it's complementary universe on the other side of the portal.

There was another change within the Round Door. It looked like rain but the drops were falling upwards and magic was starting to fizz around the places where it struck the portal's edge. Suddenly, and quite without offering any explanation, it turned in on itself and imploded out of existence, in exactly the same way that an iceberg doesn't.

At the same moment Rincewind threw the globe into the air and watched closely as it became a shining octarine meteorite falling upwards into the troposphere, accelerating through the stratosphere and mesosphere, until it was a distant but unmistakable dagger carving its way through the Ionosphere. Then it, too, disappeared in a flash of reality.

Not being one to let an opportunity for expounding something that everyone already knew pass by, the Lecturer in Recent Runes said, 'It's gone!'

'Yes,' Rincewind sat on the Luggage, which vibrated almost imperceptibly in the arboreal equivalent of a purr, 'I think that this is the end of our connection to Roundworld, which is a shame. I liked the way things worked there. They used science and reason to deal with their problems, as opposed to enchantment and swords. The books my good friend wrote about us were very popular, but now he's gone there won't be any more stories. Like that funny thing that happened with the Head of Unforseen Circumstances when he had to visit the Quirm College for Young Ladies. Or that interdisciplinary trip to Pseudopolis to argue with the faculty of Brazeneck College during the Big Thing War.'

Rincewind's monologue had become introspective enough to persuade the other wizards that it was time to find something to eat. They wandered away in ones and twos, following their stomachs towards the Dining Hall. After a minute the Wizzard stood up and turned to regard the Luggage, it looked as anxious as a travelling accessory can, its fretwork radiated fretfulness.

After breaking the habit of a self-preserving lifetime, Rincewind patted it on the lid, 'Come on then,' the Luggage seemed to hold its breath. 'We need to pack. There's someone I need to catch up with, we're taking a trip to Bes Pelargic.' And with that the pair left the courtyard, the University and Ankh Morpork behind them for the last time.

[*] Not least of which was a highwayman who forced money onto the construction workers. They were not unhappy about this state of affairs until the coins transformed back into their original mineral state - quartz, embedded in a half ton of granite - some new trousers, along with several jars of soothing ointment, were quickly deployed from New Ankh Station.

[†] Rather surprising a gnome having a heated debate with a raven about a recently borrowed, unreturned lawnmower.

[‡] A temporal agitator is a potion which allows the consumer to move half an hour back or forth within their own timeline, useful for if you missed Early Tea or get peckish before Second Dinner.

[§] The forest shattering new idea was that, rather than the orthodox and widely held belief in reincarnation as a thousand rolls of lavatory paper, the good would be rewarded with a new life as a hat stand, the most righteous having an integrated umbrella rack.

[**] With a knob on the end!

[††] The number between seven and nine is dangerously magical and can have rather unpleasant effects in a strong magical field, such as the one found on the Discworld. Any wizard who utters it is likely to find themselves abruptly surrounded by nauseatingly shaped creatures who would like nothing more than to become intimately acquainted with their inner workings.