Extracts are preparations, usually of a semi-solid consistency, containing the active parts of various plants extracted in one of several ways. In the case of some extracts, the juice of the fresh plant is simply pressed out and puri?ed; in the case of others the active principles are dissolved out in water, which is then to a great extent driven o? by evaporation. Other extracts are similarly made by the help of alcohol, and in some cases ether is the solvent.
Health Encyclopedia