" Her books on alchemy were marvellous objects, every page a work of the engraver's art, but they nowhere contained instructions like "Be sure to open a window". They did have instructions like "Adde Aqua Quirmis to the Zinc untile Rising Gas Yse Vigorousky Evolved", but never added "Don't Doe Thys Atte Home" or even "And Say Fare-Thee-Welle to Thy Eyebrows. "

― Terry Pratchett , Feet of Clay (Discworld, #19; City Watch, #3)