From the Introduction: "The present manual of our native herbal simples seeks rather to justify their uses on the sound basis of accurate chemical analysis, and precise elementary research. Hitherto medicinal herbs have come down to us from early times as possessing only a traditional value, and as exercising merely empirical effects. Their selection has been commended solely by a shrewd discernment, and by the practice of successive centuries. But to day a closer analysis in the laboratory, and skilled provings by experts have resolved the several plants into their component parts, and have chemically determined the medicinal nature of these parts, both singly and collectively. So that the study and practice of curative British herbs may now fairly take rank as an exact science, and may command the full confidence of the sick for supplying trustworthy aid and succour in their times bodily need."