Science of Discworld III

Jack Cohen, Figments of Reality: the origins of the curious mind (Cambridge University Press, 1997).

NINE
AVOIDING MADEIRA
    T HE JOINER WAS AMAZED, AS he told his mates in the pub after work
    ‘– so I was just finishing, and this feller comes down the ladder and says beggin’ your pardon, sir, but I’d just like to check that bulkhead, please. Nothing wrong with it, says I, it’s as sound as a bell. Then he says, right, right, of course, but I’ve just got to check something. He pulls this piece of paper out of his pocket and reads it careful, and says he’s got to check that the new timber hasn’t got a rare tropical worm that’ll leave it looking like good wood but weaken it so much that the ship will take in too much water and will have to put in to Madeira for repairs, or something, possibly. I’ll soon see about that, says I and whacks it with my hammer and, blow me, it cracks in half. I’d have sworn it was prime timber, too. Little worms everywhere!’
    ‘Funny you should say that,’ said the man opposite. ‘One of ’em came up when I was working and asked if he could look at the copper nails I was usin’. Well, he takes out a knife, scrapes away at one, it’s a bit of rubbish iron under a skin ’o copper! Had to do half a day’s work again! Beats me how he knew. Tom said the chandler swore they were all copper when he supplied ’em.’
    ‘Hah,’ said a third man, ‘one came up to me and said what would I do if a giant squid pulled the ship under. I told him I’d do nothing,being as I live in Portsmouth.’ He drained his mug. ‘Damned thorough, these inspectors.’
    ‘Yeah,’ said the first man, reflectively. ‘They think of everything …’
    ‘A goose is an inconvenient bird, I’ve always thought,’ said Mustrum Ridcully, carving it. ‘Just a bit too much for one but not quite enough for two.’ He extended a fork. ‘Anyone else want some? Rincewind, just get the man to send up some more oysters, will you? What do you say, gentlemen? Another six dozen? Let’s push the boat out, eh? Hahah …’
    The wizards had taken rooms at an inn, and the owner, watching the bustling staff down in his kitchen, was already thinking happily of an early retirement.
    Money had not been a problem. Hex had merely teleported some from a distant bank. The wizards had debated the moral implications of this for some time, with their mouths full, but had come down in favour of the idea. They were, after all, Doing The Right Thing.
    Only Ponder wasn’t eating much. He nibbled a biscuit and updated his notes, before announcing: ‘We have covered everything, Archchancellor. The nails, the leaking water barrels, the defective compass, the bad meat … there were nine reasons why the Beagle would have called in at the island of Madeira. Hex believes the giant squid may be a red herring. As for the nine … yes, I think we have assured that they will no longer occur.’
    ‘Remind me why that’s important, will you?’ said the Dean. ‘And pass the wine, Mustrum.’
    ‘Without this intervention it’s more than likely that Darwin will leave the ship at Madeira, should the Beagle call there,’ said Ponder. ‘He will be terribly seasick on the voyage.’
    ‘Madeira being –?’ said the Dean.
    ‘One of a group of islands on the way, Dean. After that it’s a longhaul down to the South Atlantic, round the bottom of South America with a few stops, and straight up to the Galapagos Islands.’
    ‘Down, bottom, up,’ muttered the Dean. ‘How can anyone get the hang of globular navigation?’
    ‘The phenomenon we call The Love Of Iron, sir,’ said Ponder, smoothly. ‘We only find it in rare metals that drop from the sky, but it’s very common here. Iron here tries to point north.’
    Silence fell around the table.
    ‘North? Is that the bit at the top?’ said Ridcully.
    ‘Conventionally, sir, yes,’ said Ponder, and rather foolishly added, ‘but on a globe it doesn’t really matter, of course.’
    ‘Ye gods,’ muttered the Dean, putting his hand over his eyes.
    ‘How does the iron know which way to point?’ Ridcully persisted. ‘Metal can’t think.’
    ‘It’s a bit like … like peas turning to follow the Sun, sir,’ hazarded Ponder, not sure if they actually did; perhaps it was pea farmers.
    ‘Yes, but peas are living things,’ said Ridcully. ‘They … know about the Sun, right?’
    ‘Peas aren’t exactly renowned for their brains, Archchancellor,’ said the Chair of