Based on extensive archival research in Peru, Spain, and Italy, Making Medicines in Early Colonial Lima, Peru examines how apothecaries in Lima were trained, ran their businesses, traded medicinal products, prepared medicines, and found their place in society. In the book, Newson argues that apothecaries had the potential to be innovators in science, especially in the New World where they encountered new environments and diverse healing traditions. However, it shows that despite experimental tendencies among some apothecaries, they generally adhered to traditional humoral practices and imported materia medica from Spain rather than adopt native plants or exploit the region's rich mineral resources. This adherence was not due to state regulation, but reflected the entrenchment of humoral beliefs in popular thought and their promotion by the Church and Inquisition.