Abstract: A method of making herbal extracts entails continuously percolating a solvent through a bed of herbaceous material in the vessel at a temperature between room temperature and about 60° C. to produce an extract comprising active principles contained in the herbaceous material. The thus produced extract is highly concentrated and contains a large proportion of the active principles in the raw material, and can be used in lower unit doses to provide enhanced medicinal treatment. The solvent is a mixture of distilled water and catalyst altered water. The mixture enhances the extraction of the active principles for improved treatment, and improves the quality and processing of the extract.