Gunpowder made its first appearance in China circa 800 and in Europe around 1250 .
but it occurs to me that there could have been explosions far earlier. You don’t need gunpowder or nitrated compounds to give you a big boom. There have been devastating explosions in grain elevators and mills. People have been grinding flour in mechanized mills since at least Roman times, and maybe earlier. Even without the mechanization, all you really need is a large collection of flour dust, a way to disperse it, and a source of ignition. European mills frequently had fireplaces. All you’d need was for someone to drop a bag of flour from on high, have it rip against something, and produce a sufficient dispersed cloud of flour.
You’d think that there’d be lots of opportunity for this in the many centuries between the first stockpiling of ground flour and the modern world, especially since, until pretty recently, caqndles and other open flame were the only means of providing light (and enclosing the flame in a glass lantern, as they did in the powder rooms on ships wasn’t really an option for most of that time). Yet the earliest flour explosion I find reference to on the 'net is from Turin in 1785. There are plenty of references to it online, but bhere’s one:
http://www.safetynet.de/Publications/articles/paper2.pdf
Anybody hear about anything earlier? Or have any idea why there aren’t any accounts of such things until so late, well after the introduction of gunpowder? What, for that matter, would they have called an “explosion” back then?