On The Sources Of The Homeopathic Materia Medica: Three Lectures (1877) is a book written by Richard Hughes. The book is a collection of three lectures given by the author in 1877. The lectures focus on the sources of the homeopathic materia medica, which is a collection of substances used in homeopathy to treat various illnesses.The first lecture discusses the sources of the materia medica, including the various plants, animals, and minerals used...