In many old houses once you break through the lath-and-plaster (or it breaks on you and you need to repair it) there is a disgusting amount of "coal dust" that comes out. Where do these carbon particles come from? Yes old houses used to be heated with coal. But I assume the furnaces had chimneys to vent the combustion products. So why is there so much dust within walls and ceilings?
posted by MonkeySaltedNuts on Oct 16, 2007 - 21 answers