The mixture is poured into a pressure chamber, and hydrogen gas is added to 40-60 psi. As the hydrogen gas reacts with the mixture, the pressure is observed to drop. Hydrogen is periodically added until the pressure remains constant. Evaporation leaves behind the methamphetamine. As pressure drops, add hydrogen until no pressure drop is seen.
Conversion is complete.
Hydrogen Chloride Gas is then bubbled through the ether solution to produce meth-amphetamine. This method is very fast, taking as little as two hours, and results in especially clean methamphet- amine. It is also a particularly dangerous process, since reactive metals are explosive when exposed to water, and anhydrous ammonia is violently corrosive to lung tissue. Once methamphetamine is made, it may be washed with acetone to remove impurities and bring its finished color from shades of orange to yellow to white. Investigators can expect to find several cans of ac-etone or alcohol, hot plates and glass or plastic jars used for the crystallization process.