I've been a long time fan of the Brechts through my long history with the Birthright setting. At its height several years ago an article was brought to my attention discussing the existence of black powder in Cerilia.

I'm not sure of the source now, or if my memory even serves me correctly, but i seem to recall that Muden had closely guarded secrets in the design of an astrolabe (or was it sextant?) and the development of a black powder/gunpowder they called "Hellfire".