I have to ask just how a toxin-filled world would even be capable of anthropologically supporting the steps upwards to an industrial revolution. Even fluctuations in weather conditions on a [i]weekly[/i] basis could likely lead to a lot of "coastal" settlements along the miasma sea to become virtually depopulated just because of a stray wind pattern. You can't really make the comparison to our own oceans, because the oceans themselves were a symbiotic part of human development. You can't fish or sail from a gaseous sea of aerosol poison. Realistically, it would make virtually anything that would have a remote chance of coming into contact with the miasma sea virtually unnavigable, which itself would stifle most forms of travel beyond the largest and tallest of mountain chains. This is to say nothing on what could come of errant weather's effects on agricultural development. If the peaks of mountains are above the mist, the soil is going to be very rocky and not particularly conductive to anything other than grasses, mosses, and shrub-based plants, as well as some [i]very[/i] hardy trees. Couple this with the fact that almost [i]any[/i] form of precipitation would result in Acid Rain On Steroids, and I think that all of this immediately rules most forms of agriculture viably. 

	If anything, the human populations of the world would practically be constricted to - generously speaking - isolated, semi-nomadic tribes that would need to constantly relocate due to shifting wind currents that might threaten to wipe out entire permanent settlements. Barring serious advances in architecture that would likewise require incredible mega-projects - i.e. self-sealed buildings that would be required to have their own [i]virtual atmosphere[/i] to be sealed from the miasma - I can't particularly see the justification in any civilization larger than hunter-gatherers, or perhaps even ancient slave-based societies like you might see in Mesopotamia or Anatolia. But I can't envision any society gathering much traction beyond that - nevermind the myriad of advancements that is required for anything beyond nomadic societies: Any serious mining or metalworking operation requires permanence, and when the world as a whole is threatened by stray breezes of miasma that could depopulate whole towns, I don't see any serious advances in technological progress, barring some, "Aliens came and gave us airships" shit.