‘Oh? Er . . . well done,’ said Blouse.
‘Take the pictures, Otto,’ said de Worde. These gentlemen have a war to fight.’
‘Out of interest, Mr de Worde,’ Blouse interrupted, ‘how did you get the pictures back to your city so quickly? Magic, I assume?’
‘What?’ De Worde looked momentarily off balance. ‘Oh no, sir. Wizards are expensive and Commander Vimes has said that there is going to be no first use of magic in this war. We send things by pigeon to our office in the keep and then by clacks from the nearest trunk tower.’
‘Oh, really?’ said Blouse, showing rather more animation than Polly had seen up until now. ‘Using numbers to indicate a scale of grey shades, perhaps?’
‘Mein Gotts!’ said Otto.
‘Well, yes, as a matter of fact we do,’ said de Worde. ‘I’m very impressed that you—’
‘I have seen the clacks towers on the far bank of the Kneck,’ said Blouse, his eyes lighting up. ‘Very clever idea, using big shuttered boxes rather than the old-fashioned semaphore arms. And would I be right in my surmise that the box on the top, which opens its shutters once a second, is a kind of system, er, clock that makes certain the whole clacks line keeps in step? Oh, good. I thought so. One beat a second is probably the limit of the mechanisms, so no doubt all your efforts now are concentrated on maximizing the information content per shutter operation? Yes, I imagined that would be the case. As for sending pictures, well, sooner or later all things are numbers, yes? Of course, you would use each of the two columns of four boxes to send a grey code, but it must be very slow. Have you considered a squeezing algorithm?’
De Worde and Chriek exchanged a glance. ‘Are you sure you haven’t been talking to anyone about this, sir?’ said the writer.
‘Oh, it’s all very elementary,’ said Blouse, smiling happily. ‘I had thought about it in the context of military maps which are, of course, mostly white space. So I wondered if it would be possible to indicate a required shade on one column and, on the other side, indicate how far along that rank that shade would persist. And a delightful bonus here is that if your map is simply in black and white, then you have even more—’
‘You haven’t seen inside a clacks tower, have you?’ said de Worde.
‘Alas, no,’ said Blouse. ‘This is simply “thinking aloud” based on the de facto existence of your picture. I believe I can see a number of other little mathematical, ahem, tricks to make the passage of information even swifter, but I am sure these have already occurred to you. Of course, a fairly minor modification could potentially double the information burden of the whole system at a stroke. And that is without using coloured filters at night, which I’m sure even with the overhead of extra mechanical effort would surely increase throughput by— I’m sorry, did I say something wrong?’
The two men both wore a glazed expression. De Worde shook himself. ‘Oh . . . er, no. Nothing,’ he said. ‘Er . . . you seem to have got the grasp of things quite . . . quickly.’
‘Oh, it was perfectly straightforward once I started thinking about it,’ said Blouse. ‘It was exactly the same wr>en I had to redesign the department’s filing system, you see. People build something that works. Then circumstances change, and they have to tinker with it to make it continue to work, and they are so busy tinkering that they cannot see that a much better idea would be to build a whole new system to deal with the new circumstances. But to an outsider, the idea is obvious.’
‘In politics as well as, er, filing systems and clackses, do you think?’ said de Worde.
Blouse’s brow wrinkled. ‘I’m sorry, I don’t think I follow . . .’ he said.
“Would you agree that sometimes a country’s system is so out of date that it’s only the outsiders that can see the need for wholesale change?’ said de Worde. He smiled. Lieutenant Blouse did not.
‘Just a point to ponder, maybe,’ said de Worde. ‘Er . . . since you wish to tell the world of your defiance, would you object if my colleague takes your picture?’
Blouse shrugged. ‘If it gives you any satisfaction,’ he said. ‘It’s an Abomination, of course, but these days it’s hard to find something that isn’t. You must tell the world, Mr de Worde, that Borogravia won’t lie down. We will not give in. We will fight on. Write that down in your little notebook, please. While we can stand, we will kick!’
‘Yes, but once again may I implore you to—’
‘Mr de Worde, you have I am sure heard the saying that the pen is mightier than the sword?’
De Worde preened a little. ‘Of course, and I—’
‘Do you want to test it? Take your picture, sir, and then my men will escort you back to your road.’
Otto Chriek stood up and bowed to Blouse. He unslung his picture box.
‘This vill only take vun minute,’ he said.
It never does. Polly watched in horrified fascination as Otto took picture after picture of Lieutenant Blouse in a variety of what the lieutenant thought were heroic poses. It is a terrible thing to see a man trying to jut out a chin he does not, in fact, have.
‘Very impressive,’ said de Worde. ‘I just hope you live to see it in my paper, sir.’
‘I shall look forward to it with the keenest anticipation,’ said Blouse. ‘And now, Perks, please go along with the sergeant and put these two gentlemen back on their way.’
Otto sidled up to Polly as they walked back to the cart. ‘I need to tell you somezing about your vampire,’ he said.
‘Oh, yes?’
‘You are a friend of his?’ said Otto.
‘Yes,’ said Polly. ‘Is something wrong?’
‘Zere is a problem . . .’
‘He’s got twitchy because he has run out of coffee?’
‘Alas, if only it vas that simple.’ Otto looked awkward. ‘You have to understand that ven a vampire forgoes . . . the b-vord, there is a process that ve call transference? Ve force ourselves to desire something else? For me this vas not painful. I crave the perfection of light and shade. Pictures are my life! But your friend chose . . . coffee. And now he has none.’
‘Oh. I see.’
‘I vunder if you do. It probably seemed so sensible to him. It is a human craving, and no one minds if you say, as it might be, “I am dying for a cup of coffee”, or “I’d kill for a cup of coffee”. But without coffee, he vill, I am afraid . . . revert. You understand, this is very difficult for me to talk about. . .’ Otto trailed off.
‘By revert you mean . . . ?’
‘First vill come mild delusions, I think. A psychic susceptibility to all kinds of influences from who knows vhere, and vampires can hallucinate so stronkly zat zey can be contagious. I zink zat is happening already. He vill become . . . erratic. This may last for several days. And then his conditioning vill break and he vill be, vunce again, a true vampire. No more Mr Nice Coffee Drinker Guy.’
‘Can’t I do anything to help him?’
Otto reverentially laid his picture box in the back of the cart, and turned to her. ‘You can find him some coffee, or . . . you can keep a vooden stake and a big knife ready. You vould be doink him a favour, believe me.’
‘I can’t do that!’
Otto shrugged. ‘Find someone who vill.’
‘He is amazing!’ said de Worde, as the cart rocked back down through the trees. ‘I know the clacks is against your religion, but he seems to understand all about it.’
‘Like I said, sir, he assesses stuff,’ said Jackrum, beaming. ‘Mind like a razor.’
‘He was talking about clacks algorithms that the companies are only just now investigating,’ said de Worde. ‘That department he was talking about—’
‘Ah, I can see nothing gets past you, sir,’ said Jackrum. ‘Very hush-hush. Can’t talk about it.’
‘To be frank, sergeant, I’d always assumed that Borogravia was, well . . . backward.’
Jackrum’s smile was waxy and bright. ‘If we seem to be a long way back, sir, it’s only so’s we can get a good run-up.’
‘You know, sergeant, it’s a great shame to see a mind like that wasted,’ said de Worde, as the cart lurched in a rut. ‘This is not an age of heroes and famous last stands and death-or-glory charges. Do your men a favour and try to tell him that, will you?’
‘Wouldn’t dream of it, sir,’ said Jackrum. ‘Here is your road, sir. Where will you be heading now?’