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 frangula, 4 fluidounces.
Alcohol, 1 fluidounces.
Simple elixir, 14 fluidounces.
Carbonate of magnesium, a sufficient quantity.
Triturate the fluid extract in enough magnesium carbonate to form a creamy mixture, then add the simple elixir, and filter. Each fluidrachm represents fifteen grains of buckthorn.