This is made when the stalk, bark, wood or other thick or hard parts of vegetable matter are to be used, which do not readily give up the required substances which they contain. The process usually consists of adding 1 ounce (30 grams) of chopped-up pieces of the plant to 1 pint (500 ml.) of water, and then boiling the mixture until about one quarter of the liquid has been soaked up or has evaporated. An alternative method is to boil the mixture for fifteen minutes, and then let it stand for ten.
This is made when the required substance is contained in the leaves, flowers or other soft or thin parts of the plant. The process is much the same as making tea. 1 ounce (30 grams) of the minced, group or finely chopped-up plant is put in a warm container, and then 1 pint (about 500 ml.) of boiling water is added. This is left to brew for a quarter of an hour.
This is used when the application of heat might release into the water unwanted substances, or destroy the properties of others. The cut-up or powdered roots or other parts of the plant are added to cold water, usually in the ratio of an ounce to a pint. No fixed time applies to how long soaking mixtures are left.
Whether the medicine has been obtained by decoction, infusion or soaking, as soon as it is ready it should be strained. It should be taken or applied within a day from preparation.