The National Formulary makes this elixir by mixing three and three-quarter fluidounces of spirit of phosphorus, sixteen minims of oil of star anise, nine fluidounces of alcohol, and aromatic elixir enough to make sixteen fluidounces. The oil of star anise is added to the spirit of phosphorus, then the alcohol, and the mixture is shaken until it forms a clear liquid, after which the aromatic elixir is added in small portions. Agitate after each addition until a clear mixture results. This elixir should be kept in a cool, dry place, in amber vials, and should not be made in large quantities. Each fluidrachm contains one-fiftieth of a grain of phosphorus.