[RightWhale]

Alchemists didn't use the same symbols for elements and processes that we do now. Their writing might seem just so much mysticism until it is seen that they are describing chemical processes. Thus the red dragon might be a form of sulfur. By writing in this allegorical style, they would also have protected their craft since none but initiates could read with understanding. It was a pre-scientific age, so don't expect a lot of good science; their knowledge was severely limited by modern standards.

[Bernard Marx]

Yeah, I'm familiar with the secretive nature of alchemy and the guilds in general. Now that you mention the red sulfur/dragon connection it rings a bell: I've run into it before. It might be key to the question I've been mulling about the dragon tradition in England and why dragons play such an important role in both Orient and Occident. Sulfur's an important ingredient in gunpowder and it's just plain nasty stuff when ignited. It's also found near fiery volcanoes which have a way of bringing famine and pestilence to affected areas.