Silt skimmers not working in the desert is nonsensical

It doesn’t make sense that you can have a floating boat on silt and not on land. It’s psionics. Why would it even care what is below the vessel? I am aware of Troy Dennings ad hoc explanation in The Obsidian Oracle about psionicists having to imagine that the Sea of Silt used to be an ocean to operate the vessels. It didn’t make a lick of sense then, and doesn’t make sense now.

Furthermore, the lack of rivers really makes trade difficult. Having “silt skimmers” traversing the desert would make trade viable.

I assume that the generally uneven surface on land is what makes them impractical. Not that they couldn’t work, just that they aren’t that efficient. However, a psionically driven warship is another matter, though perhaps uneven land surfaces makes it harder to control while giving a smooth ride?


They wouldn’t even need to be psionically levitated to travel on land; wheeled craft powered by sail would fly across the salt flats of the Great Ivory Plains.

Give everyone cool-looking goggles, and you have the beginnings of “sandpunk” right there.


Perhaps they could be limited to the roads. That would also make all the raids on trade caravans a lot more realistic, as it makes it easier to pinpoint where a trade caravan will be eventually.

Yeah. Sword and Sandal Mad Max.

THIS pretty much.

A psionic powered ship just floats, everything else operates much like a real sailing vessel. Also Obsidian Engines are massively expensive. I would say the Wind Howdahs from ** Raiders of the Chanth (Dun #44)** are more likely available to the some of the wasteland tribes.

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I find this list of Athasian vehicles.

I’ll have to review that one to see how they work. Raiders is one thing, but I was thinking of the merchant houses. Actually, I’ve recently been on a deep dive into historical trade. Unfortunately, the Dark Sun trade as we have it now lacks verisimilitude and can’t be done. The original designers did not understand the criticality of rivers and oceans in trade. That’s what got me thinking about the silt skimmers. The silt skimmers can replace the trade on the ocean, but the trade via river is missing entirely if they cannot traverse the land somehow.

Hate it when verisimilitude gets in the way of one’s fantasy.

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One can suspend disbelief about almost anything, as long as the logic is internally consistent. That’s why people could accept Jedi shooting lightning bolts from their hands, but not a spaceship destroying another spaceship by a kamikaze attack via hyperspace, something that had never happened in Star Wars history to date.

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I completely disagree with this and think it’s based off misunderstanding the nature of trade. There are two mistaken factors here.

  1. Rivers and oceans were central to human trade because they were the most economical option in many locations. This was of course the case in Europe and the Mediterranean, but many other places as well, including European settlement in the “new world.” But it’s totally anti-historical to suggest that in the absence of this option, trade doesn’t exist. When it does exist, it’s often preferable BUT in the absence of rivers or seas, land routes become the most economical option and were in fact common throughout human history in environments without navigable water. The most famous example is the 4,000 mile Silt Road/Silk Routes and the Steppe Route between China and the Eastern Mediterranean. If you’re interested in a less Euro-centric view of world history, there’s a great book by Oxford historian Peter Frankopan called “Silk Roads” that will totally cause you to rethink what you know about history, especially if you have a view that trade can’t exist without rivers. This is a really great book if you’re interested in human history, economic history or cultural exchange period.

  2. The real world didn’t have mekillots (or any other creature) capable of pulling 100 ton land-based argosies.

The key consideration for the viability of trade is simply whether it can be done profitably. If you’re hung up on real world verisimilitude, research what’s called Ricardian Comparative Advantage which establishes the basics of when trade would be expected to occur. The key condition is simply that some city-states are capable of producing needed items at enough of a cost advantage that it’s profitable to then transport the goods and sell them elsewhere. Athas obviously satisfies this criteria. IF you had rivers, that might be your most profitable route. But transporting goods via mekillot or any type of caravan is entirely realistic in the absence of a cheaper route.

In other words, the only condition that must be satisfied is that goods must be valued in their destination city such that Sale price in City-State X > Purchase price in City State Y + Transportation Cost (Between City State Y and X). And of course if the supply gets low enough, at some point this condition must be satisfied.

It’s just completely and totally wrong to suggest as a “matter of verisimilitude” that trade couldn’t exist without rivers. On the contrary. The trade MUST exist, and the question is just at what sort of prices.


That’s not the only consideration that must be satisfied. It’s a necessary condition, but not the sole determinant.

My concern isn’t that trade would not exist, but that trade would be difficult, and not exist as it is claimed to exist within the setting. In a situation of overland trade, the only goods that will be going any distance would be good of the highest value. Overland traders will not operate at a loss simply because X is higher in Tyr than it is in Balic. In order for the trip to be profitable, the difference in price must be considerably higher and the demanded goods must be inelastic in demand. That means that any given good must be so in demand that almost any price will be paid.

We have an entire book, Athasian Emporium with goods that will never be economic to sell in another city state, because the cost of transporting the goods is likely higher than the profits that can be realised. And it’s not simply the case that you can raise your prices beyond the willingness of customers to pay. The customers will replace the goods with an inexpensive local substitute. Those mekillots have to be fed, maintained, and controlled.

Without the rivers, trade is limited to high value goods, like iron, that have inelastic demand. That doesn’t mean that the setting won’t work by taking this into account, but it does mean that Balican kola nuts aren’t sold in Tyr, barring innovations like permanent teleportation circles.

My point about trade was ancillary to my larger point that it doesn’t make sense that you could float on silt but not on sand.

That doesn’t mean that the setting won’t work by taking this into account, but it does mean that Balican kola nuts aren’t sold in Tyr

I don’t think the boxed set carefully considered the economics of all its prices, but nevertheless, the trade as proposed totally pencils out:

All prices here per the boxed set:
A mekillot costs 20 cp. It needs 300 lbs of food and 16 gallons (80 lbs) of water a day.
A crew member (soldier/driver/etc) can be hired for .2 bits per day. A crew of 20 therefore costs 4 cp a day. We’ll stipulate that food and water is provided as part of the contract for an additional 4 cp a day.
A 40,000 ton armored wagon can be acquired for 1,000 cp.

Per the 2E distance calculator, Balic to Tyr is a journey of 10 days traveling 10 hours per day at the slowest movement rate.

The fixed cost of the 10-day caravan is 1,000 cp (wagon) + 40 cp (2 mekillots) + 40 cp (10 days of crew) + 80 cp (8 tuns of water) + 800 cp (8,000 lbs of food) + 40 cp (miscellaneous) = 2,000 CP.

The total weight of this cargo is around 18,000 lbs, leaving 22,000 lbs of cargo capacity.

Kola nuts are 4 cp per pound at their base price in the Athasian emporium. Thus we would conclude the cost of 22,000 lbs of kola nuts is 88,000 cp in Balic.

Dune Trader stipulates that prices are often double in cities where they’re rare. So that’d be 8 cp per lb. You could sell this cargo for 176,000 cp in Tyr, and turn a profit of 86,000 cp. But even if you feel this implies inelastic demand (I disagree… people would certainly buy less kola nuts at this price but it’s a luxury and nobles won’t stop buying them entirely), even if the price is just 5 cp in Tyr, then the merchant can sell his cargo for 110,000 ceramic pieces, resulting in a profit of 20,000 ceramic pieces.

Although the prices and weights aren’t really part of a holistic economic system, we can still use them to pencil out whether caravans and goods, as statted, lead to kola nuts being sold in Tyr. The answer is that they would and it’s fairly profitable to successfully transport a cargo of kola nuts from Balic to Tyr in a conventional DS argosy caravan. The merchant houses, of course, would drive their costs even lower by obtaining items at better than market rates, reusing wagons, reusing mekillots, doing better-than-average at defending their caravans, refueling at way points rather than transporting the food and water for an entire journey, etc.

If you want silt skimmers in the desert it’s fine by me. Seems like they’re badly designed for the task at hand, especially when the argosy-based trade pencils out just fine.


Surely that must be a typo in the boxed set. Given the amount of feed required to get the mekillot to the point where it is properly trained to strong enough to haul goods, surely the sale price cannot be 20 cp. I think you will agree that this is impossible, and we cannot use this impossibility as a basis for the calculation.

According to Athasian Emporium, an argosy is 10,000 cp. A mekillot costs 200 cp (although weirdly, this is the “barter price” and we never see a normal price for mekillots). A mekillot steak is 150 cp a pound! That means that the only trading any dune trader should be doing is in mekillots, then slaughtering them for the value added steaks.

I think the point about trade holds. Of course there will still be trade, but Ricardian comparative advantage will be wiped out in most cases by the cost of transporting the goods. That means narrowing down which trade goods are going to be traded, regardless of price. I suspect that would be iron, obsidian and other non perishables, while kola nuts and the like are either not traded, or traded in small quantities to the wealthy only.

I’m keen to know why. If you mean that a silt skimmer might have trouble climbing a mountainous sand dune, then I am inclined to agree with you. If on flat lands, like following a road, I don’t see why a “desert skimmer” is not analogous to travelling by sea, with all the economic implications of that.

I agree that the mekillot price is too low, but you can actually make the mekillot more than 400 times as expensive as their 2E boxed set price and the kola nut trade between Balic and Tyr will still be profitable, even without assuming repeat travel with the mekillot.

The argosy that costs 10,000 cp is one that carries 200,000 lbs. I was running the numbers for a smaller 40,000 lb one. Either way, the ability of giant transports to carry tens of thousands of pounds means that the trade, as described in the books, makes completely reasonable sense.

On the silt skimmers, I guess it’s a question of how much weight we imagine one would be capable of carrying over land. There was also a wind-powered transport described in Ivory Triangle so the idea isn’t without precedent.


I’m assuming that the load will depend on the strength of the materials and quality of the build. Assuming that floats the same as those on the sea of silt, I suppose that part of the weight of the load is offset. The relative speed of the trip would be the crucial element. Also I’m not sure about the method of propulsion.

Silt skimmers don’t really work on land for 2 reasons. For your wheel based skimmers, you’re limited by weight - wheels are huge, often hollow (and turned by undead or the like), and therefore won’t be able to sustain a huge cargo weight - although you would save on food and water for animated undead in the wheel drums. Heavy stone rollers/wheels would negate the light weight you need to make a wheel skimmer work with the wind.

Obsidian engine powered skimmers are a different problem. The Dragon Magazine article which introduced Obsidian Engines (#237) states that flying skimmer research is a non-starter, partially for weight, and also partially for the following reason:

“Furthermore, silt, for some reason, is more of a conductor of psionic energies than air (many scholars postulate that the Sea of Silt’s origins have something to do with this fact).”

So there’s something about the nature of the silt itself which is conducive (conductive?) to psionic silt skimmers that land lacks.

That said, not every caravan is a huge mekillot driven argosy. House Inika specialises in crodlu and inix based caravans that focus on small and easily carried goods (kola nuts?) and the costs for those caravans would be much lower.


Psychic impressions and auras are clearly a thing in psionics (Object reading, Aura sight, Sensitivity to Psychic Impressions, etc). It’s not unreasonable to imagine that they could contribute to the functioning of a psionically powered silt skimmer. Afterall, although psionic has a somewhat different feel than magic, it’s still not science and doesn’t operate on the same principles as science. Still if you do want some scientific basis as well. The silt creates a certain amount of buoyancy and has fluidic properties that dry land does not, this reduces the amount of levitational power required to float the skimmers. Finally if you are going to complain about something not making sense, the Sea of Silt itself makes far less sense than the skimmers that navigate it. There is no way a sea of dust could exist the way it is described. It’s obviously a fantasy thing that is meant to operate in a way more similar to water than would be possible with our physical understanding of what dust is like. Heck even the name implies this as silt in the real world is not a dry thing, but rather closely associated with water and bodies of water.


I don’t remember where I saw it, but there was a fantastic alternate description for how silt skimmers worked. Something about fluid said and under-silt air currents which made certain pathways through the silt sea passable by simply floating (apparently this is physics Liquid Sand Hot Tub- Fluidized air bed - YouTube). This creates an interesting tension where the navigators actually have to navigate the currents by sight (or perhaps with psionic/magical perception), and it also allows for drama when the currents suddenly shift.
This could also be used to explain why certain pathways are well used (stable currents) while others are known to be dangerous, or even impassable except with full psionic levitation. Which would be more expensive. The more stable currents could even be navigated without psionics at all.


In my Athas Silt Skimmers are non psionical they work on Silt, because Athasian Silt works magically as water. On Land you need a Psionical or magical addition.