'Ah. This is going to be about the privies again?' said Moist, his heart sinking. 'I feel I am responsible for the moral welfare of the young people in my charge,' said Miss Maccalariat sternly. 'You are smiling, Postmaster, but I will not be funned with.'
'Your concern does you credit, Miss Maccalariat,' said Moist. 'Special attention will be paid to this in the design of the new building, and I will tell the architect that you are to be consulted at every stage.' Miss Maccalariat's well-covered bosom inflated noticeably at this sudden acquisition of power. 'In the meantime, alas, we must make do with what the fire has left us. I do hope, as part of the management team, you will reassure people on this.' The fires of dreadful pride gleamed off Miss Maccalariat's spectacles. Management! 'Of course, Postmaster,' she said. But, mostly, Moist's job was just to . . . be. Half of the building was a blackened shell. People were squeezed into what was left; mail was even being sorted on the stairs. And things seemed to go better when he was around. He didn't have to do anything, he just had to be there. He couldn't help thinking of the empty plinth, where the god had been taken away. He was ready when dusk came. There were plenty of ladders around, and the golems had managed to shore up the floors even up here. Soot covered everything and some rooms opened on to blackness, but he climbed ever up. He struggled through what remained of the attics, and clambered through a hatch and on to the roof. There wasn't much of it. The descent of the rainwater tank had brought down a lot of burning roof with it, and barely a third remained over the great hall. But the fire had hardly touched one of the legs of the U, and the roof there looked sound. There was one of the old postal pigeon lofts there, and someone had been living in it. That wasn't too surprising. Far more people wanted to live in Ankh-Morpork than there was Ankh- Morpork for them to live in. There was a whole sub-civilization at rooftop level, up here among the towers and ornamental domes and cupolas and chimneys and— —clacks towers. That's right. He'd seen the clacks tower, and someone up here, just before his life had taken a turn for the strange. Why would a loft built for carrier pigeons have a semaphore tower? Surely the pigeons didn't use it? Three gargoyles had colonized this one. They liked clacks towers anyway - being up high was what being a gargoyle was all about - and they'd fitted into the system easily. A creature that spent all its time watching and was bright enough to write down a message was a vital component. They didn't even want paying, and they never got bored. What could possibly bore a creature that was prepared to stare at the same thing for years at a time?
Around the city, the clacks towers were lighting up. Only the University, the Palace, the Guilds and the seriously rich or very nervous ran their towers at night, but the big terminal tower on the Tump blazed like a Hogswatch tree. Patterns of yellow squares ran up and down the main tower. Silent at this distance, winking their signals above the rising mists, outlining their constellations against the evening sky, the towers were more magical than magic, more bewitching than witchcraft. Moist stared. What was magic, after all, but something that happened at the snap of a finger? Where was the magic in that? It was mumbled words and weird drawings in old books and in the wrong hands it was dangerous as hell, but not one half as dangerous as it could be in the right hands. The universe was full of the stuff; it made the stars stay up and the feet stay down. But what was happening now . . . this was magical. Ordinary men had dreamed it up and put it together, building towers on rafts in swamps and across the frozen spines of mountains. They'd cursed and, worse, used logarithms. They'd waded through rivers and dabbled in trigonometry. They hadn't dreamed, in the way people usually used the word, but they'd imagined a different world, and bent metal round it. And out of all the sweat and swearing and mathematics had come this . . . thing, dropping words across the world as softly as starlight. The mist was tilling the streets now, leaving the buildings like islands in surf. Pray, she'd said. And, in a way, the gods owed him a favour. Well, didn't they? They'd got a handsome offering and a lot of celestial cred for not, in fact, doing anything at all. Get down on your knees, she'd said. It hadn't been a joke. He knelt, pressed his hands together, and said, 'I address this prayer to any god who—' With a silence that was frightening, the clacks tower across the street lit up. The big squares glowed into life one after the other. For a moment, Moist saw the shape of the lamplighter in front of one of the shutters. As he disappeared into the dark, the tower started to flicker. It was close enough to illuminate the roof of the Post Office. There were three dark figures at the other end of the roof, watching Moist. Their shadows danced as the pattern of lights changed, twice every second. They revealed the figures were human, or at least humanoid. And they were walking towards him. Gods, now, gods could be humanoid. And they didn't like to be messed about. Moist cleared his throat. 'I'm certainly glad to see you—' he croaked. 'Are you Moist?' said one of the figures. 'Look, I—'
'She said you'd be kneeling down,' said another member of the celestial trio. 'Fancy a cup of tea?' Moist got up slowly. This was not godly behaviour. 'Who are you?' he said. Emboldened by the lack of thunderbolts, he added: 'And what are you doing on my building?'
'We pay rent,' said a figure. 'To Mr Groat.'
'He never told me about you!'
'Can't help you there,' said the shadow in the centre. 'Anyway, we've only come back to get the rest of our stuff. Sorry about your fire. It wasn't us.'
'You being—' said Moist. 'I'm Mad Al, he's Sane Alex, and that's Adrian, who says he's not mad but can't prove it.'
'Why do you rent the roof?' The trio looked at one another.
'Pigeons?' suggested Adrian. 'That's right, we're pigeon fanciers,' said the shadowy figure of Sane Alex. 'But it's dark,' said Moist. This information was considered. 'Bats,' said Mad Al. 'We're trying to breed homing bats.'
'I don't believe bats have that kind of homing instinct,' said Moist. 'Yes, it's tragic, isn't it?' said Alex. 'I come up here at nights and see those empty little perches and it's all I can do not to cry,' said Undecided Adrian. Moist looked up at the little tower. It was about five times the height of a man, with the control levers on a polished panel near the bottom. It looked . . . professional, and well used. And portable. 'I don't think you breed any kind of birds up here,' he said. 'Bats are mammals,' said Sane Alex. Moist shook his head. 'Lurking on rooftops, your own clacks . . . you're the Smoking Gnu, aren't you?'
'Ah, with a mind like that I can see why you're Mr Groat's boss,' said Sane Alex. 'How about a cup of tea?' Mad Al picked a pigeon feather out of his mug. The pigeon loft was full of the flat, choking smell of old guano. 'You have to like birds to like it up here,' he said, flicking the feather into Sane Alex's beard. 'Good job you do, eh?' said Moist. 'I didn't say I did, did I? And we don't live up here. It's just that you've got a good rooftop.' It was cramped in the pigeon loft, from which pigeons had, in fact, been barred. But there's always one pigeon that can bite through wire netting. It watched them from the corner with mad little eyes, its genes remembering the time it had been a giant reptile that could have taken these sons of monkeys to the cleaners in one mouthful. Bits of dismantled mechanisms were everywhere. 'Miss Dearheart told you about me, did she?' said Moist. 'She said you weren't a complete arse,' said Undecided Adrian. 'Which is praise coming from her,' said Sane Alex. 'And she said you were so crooked you could walk through a corkscrew sideways,' said Undecided Adrian. 'She was smiling when she said it, though.'
'That's not necessarily a good thing,' said Moist. 'How do you know her?'
'We used to work with her brother,' said Mad Al. 'On the Mark 2 tower.' Moist listened. It was a whole new world. Sane Alex and Mad Al were old men in the clacks business; they'd been in it for almost four years. Then the consortium had taken over, and they'd been fired from the Grand Trunk on the same day that Undecided Adrian had been fired from the Alchemists' Guild chimney, in their case because they'd spoken their mind about the new management and in his case because he hadn't moved fast enough when the beaker started to bubble. They'd all ended up working on the Second Trunk. They'd even put money into it. So had others. It had all kinds of improvements, it would be cheaper to run, it was the bee's knees, mutt's nuts and various wonderful bits of half a dozen other creatures. And then John Dearheart, who always used a safety lanyard, landed in the cabbage field and that was the end of the Second Trunk. Since then, the trio had done the kinds of jobs available to new square pegs in a world of old round holes, but every night, high above, the clacks flashed its messages. It was so close, so inviting, so . . . accessible. Everyone knew, in some vague, half-understood way, that the Grand Trunk had been stolen in all but name. It belonged to the enemy.
So they'd started an informal little company of their own, which used the Grand Trunk without the Grand Trunk's knowing. It was a little like stealing. It was exactly like stealing. It was, in fact, stealing. But there was no law against it because no one knew the crime existed, so is it really stealing if what's stolen isn't missed? And is it stealing if you're stealing from thieves? Anyway, all property is theft, except mine. 'So now you're, what was it again . . . crackers?' Moist said. 'That's right,' said Mad Al. 'Because we can crack the system.'
'That sounds a bit over-dramatic when you're just doing it with lamps, doesn't it?'
'Yes, but “flashers” was already taken,' said Sane Alex. 'All right, but why “Smoking Gnu”?' said Moist. 'That's cracker slang for a very fast message sent throughout the system,' said Sane Alex proudly. Moist pondered this. 'That makes sense,' he said. 'If I was a team of three people, who all had a first name beginning with the same letter, that's just the kind of name I'd choose.' They'd found a way into the semaphore system, and it was this: at night, all clacks towers were invisible. Only the lights showed. Unless you had a good sense of direction, the only way you could identify who the message was coming from was by its code. Engineers knew lots of codes. Ooh, lots. 'You can send messages free?' said Moist. 'And nobody notices?' There were three smug smiles. 'It's easy,' said Mad Al, 'when you know how.'
'How did you know that tower was going to break down?'
'We broke it,' said Sane Alex. 'Broke the differential drum. They take hours to sort out because the operators have to—' Moist missed the rest of the sentence. Innocent words swirled in it like debris caught in a flood, occasionally bobbing to the surface and waving desperately before being pulled under again. He caught 'the' several times before it drowned, and even 'disconnect' and 'gear chain', but the roaring, technical polysyllables rose and engulfed them all. '—and that takes at least half a day,' Sane Alex finished. Moist looked helplessly at the other two. 'And that means what, exactly?' he said. 'If you send the right kind of message you can bust the machinery,' said Mad Al. 'The whole Trunk?'
'In theory,' said Mad Al, 'because an execute and terminate code—' Moist relaxed as the tide came back in. He wasn't interested in machinery; he thought of a spanner as something which had another person holding it. It was best just to smile and wait. That was the thing about artificers: they loved explaining. You just had to wait until they reached your level of understanding, even if it meant that they had to lie down. '—can't do that any more in any case, because we've heard they're changing the—' Moist stared at the pigeon for a while, until silence came back. Ah. Mad Al had finished, and by the looks of things it hadn't been on a high note. 'You can't do it, then,' said Moist, his heart sinking. 'Not now. Old Mr Pony might be a bit of an old woman but he sits and niggles at problems. He's been changing all the codes all day! We've heard from one of our mates that every signaller will have to have a personal code now. They're being very careful. I know Miss Adora Belle thought we could help you, but that bastard Gilt has locked things up tight. He's worried you're going to win.'
'Hah!' said Moist. “We'll come up with some other way in a week or two,' said Undecided Adrian. 'Can't you put
it off until then?'
'No, I don't think so.'
'Sorry,' said Undecided Adrian. He was playing idly with a small glass tube, full of red light. When he turned it over, it filled with yellow light. 'What's that?' Moist asked. 'A prototype,' said Undecided Adrian. 'It could have made the Trunk almost three times faster at night. It uses perpendicular molecules. But the Trunk's just not open to new ideas.'
'Probably because they explode when dropped?' said Sane Alex. 'Not always.'
'I think I could do with some fresh air,' said Moist. They stepped out into the night. In the middle distance the terminal tower still winked, and towers were alight here and there in other parts of the city. 'What's that one?' he said, like a man pointing to a constellation. 'Thieves' Guild,' said Undecided Adrian. 'General signals for the members. I can't read 'em.'
'And that one? Isn't that the first tower on the way to Sto Lat?'
'No, it's the Watch station on the Hubwards Gate. General signals to Pseudopolis Yard.'
'It looks a long way off.'
'They use small shutter boxes, that's all. You can't see Tower 2 from here - the University's in the way.' Moist stared, hypnotized, at the lights. 'I wondered why that old stone tower on the way to Sto Lat wasn't used when the Trunk was built? It's in the right place.'