This section is from the "Elixirs And Flavoring Extracts. Their History, Formulae, & Methods of Preparation" book, by John Uri Lloyd. Also available from Amazon: Elixirs and flavoring extracts,: Their history, formulae, and methods of preparation;
Fluid extract of gentian, 1/2 fluidounce
Solution of citrate of ammonium, 1 fluidounce
Tincture of chloride of iron, 1/2 fluidounce
Simple elixir, carbonate of magnesium,
distilled water, of each a sufficient quantity.
Triturate the fluid extract of gentian in a mortar with carbonate of magnesium in amount sufficient to form a thick paste, and then gradually add four fluidounces of distilled water and filter. Mix the tincture of chloride of iron with the solution of citrate of ammonium and add to the preceding filtrate, and then add of simple elixir a sufficient amount to make the whole measure sixteen fluidounces.
Each fluidrachm (teaspoonful) of the finished elixir contains about two minims each of tincture of chloride of iron and fluid extract of gentian. The citrate of ammonium is introduced to prevent blackening of the elixir, as explained under elixir of calisaya and chloride of iron with citrate of ammonium. '
Elixir of gentian and chloride of iron was mentioned first in the Druggists' Circular, 1871, and afterward (1873) Prof. Joseph P. Remington presented a process through the American Journal of Pharmacy. The Newark Pharmaceutical Association (1871) recommended an elixir of gentian and pyrophosphate of iron, and at a still earlier date Mr. William B. Thompson had presented a process for this elixir through the Druggists' Circular.