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I’m trying to build a world with steampunk-level technology, but would like it if compasses didn’t work/exist (or, failing that, if they were prohibitively expensive or difficult to get hold of). The technology level of the world excludes the possibility of it being too advanced a device, so I’m wondering: why wouldn’t a compass work in this world?

There is magic in this world, but it’s more limited to the existence of mythological creatures, rather than completely reality-altering stuff, so a more realistic/scientific reason would be preferable if possible.

Other modes of navigation are possible (such as using the sun or stars), but I’m currently envisaging a character flying dragonback over open ocean with no landmarks, it’s nighttime, and the sky is cloudy/it’s stormy. I’d like to exclude the possibility of “oh, I’ll just get the compass from my pocket” as a solution to them getting lost.

I would also prefer it to be a constant thing for this world, rather than there being a convenient solar storm or something. I also know that magnetic fields are a bit changeable, so compass navigation wouldn’t be an exact science anyway, but getting rid of compasses entirely is what I’m aiming for.

If it’s not plausible to have compasses just not exist (idk why, maybe there’s some crazy multiple magnetic field thing going on that would make compasses pointless), why might they be really hard to get hold of? (I’m talking only the richest of the rich might own one.)

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    $\begingroup$ Maybe the world's magnetic field is not a simple dipole. Maybe the molten core rotates independently of the surface, so the orientation of the magnetic field relative to the surface changes in a short time. (Disclaimer: I do not understand what makes Earth's magnetic field.) $\endgroup$ – Anton Sherwood Nov 5 '20 at 3:44
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    $\begingroup$ note compasses are not that helpful without decent maps and preferably a reliable time piece. $\endgroup$ – John Nov 5 '20 at 3:53
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    $\begingroup$ If there is abundant lodestone/iron deposits, they would generate enough interference to make compasses useless. $\endgroup$ – DWKraus Nov 5 '20 at 4:05
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    $\begingroup$ Earth's magnetic field does occasionally switch from a nice dipole to a quadrupole, which leads to a dramatic decrease in perceived field intensity on the surface of the planet. It may be doing it right now -- the intensity of the magnetic field has decreased about 15% during the last 150 years, and the decrease is accelerating. See geomagnetic reversal. It may be that the dragon rider is living during such a reversal. $\endgroup$ – AlexP Nov 5 '20 at 8:03
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    $\begingroup$ Maybe compasses simply weren't invented? $\endgroup$ – Erik Nov 5 '20 at 8:45

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Large magnetic ore deposits everywhere, altering the reading of the magnetic North on a compass.

They have noticed that a magnetized needle aligns along a preferential direction, but that direction changes with the place, so it is unusable for telling the North.

Incidentally the large magnetic ore deposits would be good for your steampunk people, because they would have large amount of metals at easy reach.

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    $\begingroup$ I realise like this as an idea, handy for the steampunk setting! I’m way out of my depth with any science behind this though - would magnetic interference still happen when at high altitude (i.e. on dragonback), or would it only/mainly affect people when at ground level near such ore deposits? $\endgroup$ – K. Price Nov 6 '20 at 1:08
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    $\begingroup$ Should be fine at high altitude if the deposits are big enough -- I think you'd get something that looks like the mars photo in another answer $\endgroup$ – C. McCracken Nov 6 '20 at 1:16
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    $\begingroup$ And as we could expect that cities would prosper on metal-rich areas, compass would also be usefull for travellers. $\endgroup$ – Kepotx Nov 6 '20 at 7:29
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    $\begingroup$ The effect of ore outcroppings on a magnetic compass would appear to be very similar to that of islands on oceanic swells and currents. And it is possible to navigate in that environment with minimal equipment, although it takes a very high level of skill. $\endgroup$ – Mark Morgan Lloyd Nov 6 '20 at 21:59
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Perhaps too easy, but what if your planet simply has no magnetic field, or at least a field too weak to be useful for navigation? Venus has almost no magnetic field, but is otherwise similar enough to Earth that if they traded places, complex life could potentially have emerged on Venus, and Earth would be a hot-house.

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    $\begingroup$ My thought too, seems like the obvious explanation. There'd be much higher levels of solar particles which for us are carcinogenous, but maybe life adapted to that somehow. There's also a risk of the atmosphere being blown away by solar wind, but as Venus shows, that's not always the case. $\endgroup$ – Mark Nov 5 '20 at 12:12
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    $\begingroup$ Earth's magnetic field regularly goes into a weakened, disorganized state that provides little shielding (and would make compasses quite useless), with no impact on surface life that has survived in the fossil record. The atmosphere itself provides plenty of shielding. What the magnetic field does is prevent loss of water (and Venus has lost almost all of its water), and that would takes many millions of years to become significant. $\endgroup$ – Christopher James Huff Nov 5 '20 at 13:08
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    $\begingroup$ @ChristopherJamesHuff I'd forgotten the impact that magnetism has on solar radiation and water loss. But could the latter potentially be dealt with through higher surface gravity / escape velocity? $\endgroup$ – James_pic Nov 5 '20 at 13:41
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    $\begingroup$ To some extent: a higher-mass, lower-density world could have Earthlike surface gravity and a higher escape velocity, and slower escape. A relatively red star would help, as long as it doesn't come with excessive flare activity. But again, it takes many millions of years to happen. The magnetic field could fade and intelligent life evolve and go extinct multiple times before the planet becomes uninhabitable. $\endgroup$ – Christopher James Huff Nov 5 '20 at 14:56
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    $\begingroup$ With no magnetic field, you will have to explain why the local Sun is not sterilizing the surface with radiation. Earth's magnetic field does a LOT to protect the surface from solar radiation, especially during flares and coronal mass ejections. $\endgroup$ – user79911 Nov 5 '20 at 20:24
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Your planet could have a magnetic field like Mars.
Instead of one large, semi-stable dipole, it looks like it has the Measles. (this causes other concerns, as you do not have a good shield against space radiation) enter image description here

Or: Your moon could have a very strong magnetic field, with the result that a magnetic compass just shows you the direction of the moon, and nothing else.

Or: Even the Sun's magnetic field could be stronger at the surface of the planet than the planet's own magnetic field. For Earth the Sun's magnetic field is only about 10 000 times weaker. Having a Sun or companion star with a magnetic field that much stronger is not an astronomical stretch, just make your system's primary a close binary with one element being a white dwarf or neutron star.

Or: Your planet could have a magnetic field exactly like that of Earth. Just as strong, just as directional. But it could "wander" around more rapidly. Earth's current North Magnetic Pole is running off towards India at a rate of about 15 km per year. This requires constant adjustment of maps to get accurate compass bearings. What if your planet's north pole moved a bit faster, say 500km per year? North today would have been NorthWest 10 years ago, and south-by-southeast 50 years ago.
enter image description here

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    $\begingroup$ oooh, I like the ease of hand-waving an extremely magnetic moon. Compass' work, but as you say, point to the moon. $\endgroup$ – CGCampbell Nov 5 '20 at 15:25
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    $\begingroup$ Hm… compass pointing to the moon would still be fairly usable to maintaining straight tracking, just as seeing the moon itself is. $\endgroup$ – Jan Hudec Nov 5 '20 at 18:43
  • $\begingroup$ Then multiple magnetic moons? $\endgroup$ – Mark Nov 6 '20 at 11:53
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    $\begingroup$ I like your idea, but I think you need to speed up the change in polar direction. Or better yet, make it multiple, rapidly moving, poles. en.wikipedia.org/wiki/North_Magnetic_Pole#/media/… You can make the declination really fast as well. No compass will be of use. $\endgroup$ – Flummox - don't be evil SE Nov 6 '20 at 19:48
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How wrong is your compass anyway?

The first thing to start with is a map. This is a map of magnetic declination. Critically what it shows is how wrong your compass is at any point in the world.
magnetic declination

This is of course only the bigger picture. If you're in an area with a lot of magnetic rock you'll find that your compass is even more unreliable on a local level.

What this means in practice for your world is simple a matter of how far off the "true" values your magnetic poles are. For people in the "civilised" regions, towards the temperate zones and equator, a magnetic compass is a reasonable tool. But if you move the magnetic poles further from the true poles then as you get further towards the arctic "adventuring" zones a compass becomes increasingly useless.

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  • $\begingroup$ I'm not sure why you believe that people don't know how to add and subtract, and don't have the skills to make a rotating graduated dial around the compass. Magnetic declination was discovered very early in the history of compass use, and compensating for it was invented immediately afterwards. It's not as if it is hard to determine magnetic declination at any point on Earth: at night, determine magnetic north from the compass, determine true north from the stars, and write down the difference on a piece of paper. $\endgroup$ – AlexP Nov 5 '20 at 11:31
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    $\begingroup$ @AlexP, most people can add and subtract, but for the most part when dealing with magnetic compasses, they don't know they need to at all, never mind how much. With that, the average person doesn't know how to determine true north from the stars, added to which, Polaris isn't a particularly bright star and usually isn't visible from here. Close to the poles the average magnetic compass ceases to work anyway because it's trying to point into the ground and can't balance enough to spin. Little details that will come back to bite. $\endgroup$ – Separatrix Nov 5 '20 at 11:50
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    $\begingroup$ Further, declination changes with time as well as space; corrections, even if known, would go out of date - just dial things up a notch or two from our world and you're there, +1. It really is striking how the low (and slowly changing) declination areas coincide with seafaring cultures that have left written records (Mediterranean, Far East) while I recall reading that Polynesian navigators relied on other methods. $\endgroup$ – Chris H Nov 5 '20 at 13:02
  • $\begingroup$ for that matter, the average person has most likely never seen, nor knowingly used a compass at all.... $\endgroup$ – CGCampbell Nov 5 '20 at 15:20
  • $\begingroup$ @CGCampbell these days? I would guess that a lot of people have compasses built into their phones. With declination tables updated off the Internet.Still useless though if there's a giant vein of iron ore sitting right below your house. $\endgroup$ – John Dvorak Nov 5 '20 at 16:47
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Machine interference

Steampunk machinery achieves things realistic machines wouldn't, but at the cost of producing extremely strong magnetic fields. While the clanks are activated, everything that is ferromagnetic is drawn to them. This has the effect that iron parts don't necessarily need to be welded or screwed into machinery, but it also means you don't want to have too many iron things in a heavily automated area.

This is actually seen in Dishonored 2, where some moving contraptions (clockwork soldiers) include this in their design:

While the head and body of a Clockwork Soldier are mechanically attached to each other, the arms and legs are magnetically attracted to the frame.


Fun fact: one of the earliest connections between magnetism and electricity was discovered when people noticed that when lightning strikes, a compass close to it will point to where the lightning hit for a moment before pointing north again.

Some real life devices can get a compass to act even crazier. If you wish to skip the electrical engineering explanation go straight to the 1:40 mark in this video to see what I mean.

I always imagined the most complex steampunk devices as having lots of such coils in them. The only extra handwaving you need to make such technology interfere with compasses has to do with the intensity of the magnetic fields involved.


Your character and/or the dragon probably have tech on them, so any compass will point to the rest of their equipment. The character may use a compass alright, but he'd have to land (not possible while flying inside a storm over an ocean), and get very far away from their belongings (not safe) to get a reading. And since staying on course requires multiple readings and path corrections, this becomes unfeasible. Only the primitive tribes, which do not use tech, manage to use compasses. Properly civilized people use a degaussed heading thingamajig in conjunction with a steam powered antikythera and a wrist watch to chart their course, but that requires either seeing the stars (not feasible in a storm), or knowing exactly where you are (doesn't seem to be the case), so they are lost anyway.

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  • $\begingroup$ Another real-movie example would be in rot13(Tbqf zhfg or penml), wherein a steel cup too close to a compass caused a navigation error that would take rot13(frireny rkgen qnlf bs geniry) to fix. $\endgroup$ – John Dvorak Nov 5 '20 at 16:41
  • $\begingroup$ @JohnDvorak are you rot13'ing that stuff to avoid giving spoilers? $\endgroup$ – The Square-Cube Law Nov 5 '20 at 16:51
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Shifting Magnetic Fields

Perhaps the molten iron core of the planet is unstable causing fluctuating magnetic fields making compasses as we know them useless.

See "The North Magnetic Pole Just Changed"

The compasses used by the rich don't use magnets but some form of magitech which is rare and expensive.

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  • $\begingroup$ Unfortunately this means too much radiation for life to be feasible, unless you also handwave that. $\endgroup$ – The Square-Cube Law Nov 5 '20 at 3:48
  • $\begingroup$ It's got magic so hand wave away........ $\endgroup$ – Thorne Nov 5 '20 at 4:21
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    $\begingroup$ @TheSquare-CubeLaw: Earth's magnetic field oscillates, reversing polarity from time to time and passing through periods where it is very weak. Life doesn't care. $\endgroup$ – AlexP Nov 5 '20 at 8:21
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    $\begingroup$ I see this as there are strong magnetic fields, they just change too often. $\endgroup$ – CGCampbell Nov 5 '20 at 15:23
  • $\begingroup$ Actually a compass that doesn't use magnet and always shows true north is a fairly simple device. It is simply a gyroscope that measures rotation of the Earth. $\endgroup$ – Jan Hudec Nov 5 '20 at 18:27
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They have a compass...

...but hand compasses are rather finicky. They don't have a very powerful magnetic element, and you need to make sure it's stable enough that the attractive force of the magnet isn't overwhelmed by the rocking of the compass body. So to get an accurate fix - accurate enough to fly by with no other landmarks - you need to hold it very still. On the back of a dragon. In flight.

If you were over land, you could land, get a fix, fly for awhile (and hope you didn't deviate too much from that course while in the air), get another fix, etc. But of course you're not over land, and dragons aren't typically known for their use as a flotation device.

Once you've lost your original track, a compass alone is not hugely useful as a navigation aid, unless you happen to be flying to one of the magnetic poles. If I'm following a track due north, and I get blown westward by the winds, I can figure I need to fly east of north... but I don't know how much, and I can't figure it out without some other kind of landmark, earthly or celestial.

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Aetheric Interference

Examples abound in fiction of magic and EM fields mixing badly.
Harry Potter's universe for example has them pretty much at odds with one another, Magic is explicitly stated to cause electrical devices to go haywire or otherwise fail.

You might not have reality-breaking magic in your universe, but if you just treat it as "Aether" and use your Magitek Steampunk stuff with it in some cases, you have an easy excuse to break technology usefully for your story.

The Aether is a fantastically useful story-telling element that lets your lightning-powered anti-gravity ship work if you can gather it in bottles, or you can use specially treated goggles to see "ghosts", or with the right fabric you can fly like a bird in it.
Basically it's the magical equivalent of Electro-magnetic fields.
However, it's can also be utterly incompatible with those same Fields.

The Aether can cause electrical devices to receive nasty power-surges, cause light to bend oddly (fun to make invisibility shields with), metal objects can float in it under the right circumstances (similar to electrical superconduction) and most relevantly, Compasses tend to point straight at the nearest concentrations of Aether for miles and go utterly bonkers when immersed in it.

Basically you can think of it as "what if magnetic fields were a gas?"

Mix and match whatever traits you like, can you breathe it safely? Is it toxic or corrosive to the wrong materials? How dense is it?
It neatly justifies gratuitous use of brass-goggles and respirators if you want it to.
It could be justified as killing the high-technology industry before it could happen. Integrated circuits and even vacuum tubes simply burn out when exposed to Aether outside of the most carefully shielded laboratories (and every natural-philosopher is using Aether in their experiments and projects, so such labs are going to be rare)

For your dragon-rider, the creature might well need Aether to fly, being a magical creature and most likely being thoroughly aerodynamically unsound like most depictions.
On top of which, the critter itself being saturated with Aether, is basically a massive electromagnet making the rider's compasses useless.

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Navigating with a compass and no good landmarks can get you lost easily. All you know then is how to get to the north or south pole, not how to get anywhere else.

I got lost with a map and a compass once - I was hiking through one of three nearly identical valleys and for 24 hours I didn't know which.

Your dragon rider has an even worse situation. The open sea has no landmarks at all. The dragon flies forward relative to the air, not relative to the ground, so if there's any wind it won't fly precisely in the direction its snout is facing. If the wind changes direction or speed, the dragon will not fly in a straight line. If there's a headwind or tailwind they could have flown a much greater or smaller distance than they think they have. And a dragon is not a precise instrument, so it cannot be relied upon to travel in a perfectly straight line at a perfectly consistent speed even in still air.

Consequently, even if the rider has looked at the compass every five minutes for the whole journey, if they've been out of sight of land for a while they could be far from where they think they are.

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Your story happens in Earth but in the middle of a geomagnetic reversal and geomagnetic field is too weak or irregular to be useful.

Geomagnetic reversals happen quite at random in the Earth - more often than one every million years -, and they take a few thousands years to complete. In that period the field - or at least its bipolar component - diminishes and grows again, but inverted. When the bipolar component is zero, the remaining geomagnetic field could be as useless as those of Venus or Mars described in other answers.

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Unlikely, but for completeness: if there are no ferromagnetic materials in the (top layer of the) planet, the compass would not be invented.

It might limit your story quite a bit to rule out iron though. And it might seem unlikely, seeing how prevalent iron is (being the most stable atom, after all).

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Organic interference. In your scenario, a person riding another living thing, the person or dragon itself could produce small but impactful amounts of disorganized EM interference. Enough to make a compass wiggle and be unreliable or not useful. This could play into the bigger steampunk world, where electronics become difficult to develop if the presence of the researchers messed it up. That'd also make functioning compasses more awkward and bulky, since they'd have to be encased or shielded.

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    $\begingroup$ Along similar thoughts, a dragon is a pretty unusual critter, most depictions would be far too heavy to fly. Perhaps the creature's biology uses bio-electricity in a big way to solve its power-to-weight ratio problems and the resultant magnetic fields make compasses useless. Easily solved by landing and moving away from your dragon, but if you're over the ocean, good luck with that! $\endgroup$ – Ruadhan Nov 5 '20 at 15:19
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Dragons are magnetic

Did you know that the chemicals Dragons need to breath fire are highly magnetic? Compass always points at Dragon, character gets lost, mission accomplished.

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There are clearly lots of better answers, but I thought it might be worthwhile to bring up a different perspective. Just like evolution, human-developed tools seem to stop when they solve problems well-enough. They don't always have to keep improving. My thought is that if something else had already solved the problem in a different way, you would not NEED to develop a compass. True, some people like creating a better mousetrap, but they don't always catch on. I realize this is not technically an answer, but it might offer an alternative explanation, if you have your own tool in mind.

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    $\begingroup$ I was looking to see if someone had posted this already, it's Columbus egg, a compass is an invention, just having it not being a thing is the easiest solution to the problem, especially if people had found other ways to find their way. $\endgroup$ – Inferry Nov 7 '20 at 6:27
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    $\begingroup$ You could even make its invention, or something like it, a plot device later on. But having no one come up with it is as natural as it gets, we have plenty of examples of things that could've been made way earlier had somebody thought of it sooner. $\endgroup$ – Inferry Nov 7 '20 at 6:36
  • $\begingroup$ @Inferry -- I agree; not being invented is the simplest. It is not very exotic, and it is not very exciting, but it is easy to justify. I wrote this prepared for an avalanche of downvotes, and I appreciate the support. $\endgroup$ – MJB Nov 9 '20 at 14:09
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The compass existed for around a thousand years before people thought of using it for navigation (it was originally a tool for divination), and making good use of them takes some skill, training, and good maps. It's entirely plausible for them to just not have been put to that use, or for the relevant characters to not have one or the knowledge and skills to use it.

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You have a small moon in a low orbit that has an extremely powerful magnetic field. (Note that this probably can't be natural.) This often dominates the planet's magnetic field.

Tables could tell you when the moon was far enough away that you could use a compass--but nobody has figured this out. Since compasses don't consistently point north nobody has realized the potential.

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The planet has a liquid interior but no iron core. The magnetic field is unstable and reverses periodically like that of the Sun (which flips every 11 years). A compass would sort of work but inaccurately, and there would be years in which it isn't usable.

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    $\begingroup$ A liquid rock core wouldn't produce a magnetic field that reverses more often, it just wouldn't produce a magnetic field. A magnetic field reversal works without any changes, though, since it could be centuries or millennia before compasses are accurate and reliable again. $\endgroup$ – Christopher James Huff Nov 7 '20 at 13:38
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Open Ocean, No Landmarks, Nighttime, Cloudy to Stormy Sky ... Compass of no use or non-existant.

Iron is needed for a compass needle, and your world just doesn’t have enough ferric material.

This would mean your steampunk machinery is non-ferric based.

However, if dragons in your world are migratory like passenger pigeons, they would be tuned in to the planetary magnetic fields through natural evolution and a small storm would not throw them off course.

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