History of fog and smoke machines

Hey, everyone, I'd really love it if someone could help me out here... A friend of mine is doing a project on the history of fog and smoke machines (particularly in Greek/Shakespearean theatre) but she's finding it ard to find anything and I thoguht maybe someone here would know where to find stuff. It's a uni project so links and things or advice on where to look would be most appreciated. Thanks everyone! -Angela