From the works of early modern physicians, such as Laurent Joubert and James Primrose, to the broadsides of the 18th century and the medical journals of the Victorian era, the literature of medicine is littered with references to "quacks" and "popular errors". Early histories of medicine, from John Friend in 1715 to THOMPSON in 1925, stress a bi-polar divide between book learned, university-trained physicians and other forms of practitioner.