DOUGLAS MIXTURE
Douglas Mixture is an old-time tonic, much esteemed by a good many breeders of pigeons and poultry. It is made by dissolving eight ounces of iron sulphate (copperas) in two gallons of water and then very slowly adding one ounce of sulphuric acid. Put in jugs and it will keep indefinitely. If a tablespoon of this is put in the drinking water occasionally, it will act as a tonic and make the blood richer. It is especially recommended for use during the molting season.