From the DOJ report, quote, Drying anthrax spores requires either a sophisticated drying machine called a lyophizer, a speed vac, or a great deal of time and space to let the spores air dry. Like a bathtub. That is, to allow the water to evaporate in the lab. Because drying anthrax is expressly forbidden by various treaties, overt use of any of these methods, if noticed, would raise considerable alarm and scrutiny.