Standard accounts of the making of medical physics as a discipline have located its birth in the invention of X-rays and the subsequent development of its technological applications. This narrative, generated by contemporary practitioners of this medical specialty, has been endorsed by historians of medicine and historians of science, and has remained unchallenged by the new interest in medical imaging developed within social studies of science. The history of medical physics is still largely unattended for its cross-displinary nature, lost between the history of physics and the history of medicine.

In this paper I show that medical physics was shaped as a discipline across physics and medical practice during the long nineteenth century, before the advent of X-rays. Medicine and physics have a long history of reciprocal interactions, but it was in the nineteenth century when ‘medical physics’ was established as a distinct academic discipline, represented by university syllabi, textbooks, instruments and practices. Moreover, I argue that nineteenth-century physics and medicine are characterized by disciplinary promiscuity, a tension which informs both the shaping of physics as a discipline and the making of medical specialties in this period. The rise of medical physics is connected, on the one hand, to the major role that medical students and medical doctors had in the production and consumption of physics treatises during the nineteenth century, the teaching and learning of physics, and its boost through educational developments which run across secondary and higher education in science and medicine. On the other hand, physics and physicists had in this period a major role in the development of scientific instruments and experimental practices which shaped not only medical physics, but also other medical specialties such as experimental physiology and public health.

This paper combines approaches from the historiographies of the rise of medical specialties and the making of scientific disciplines, and a focus on practitioners’ profiles, training, technology, textbooks and practices, to offer new historical perspectives on the making of medical physics for the use of historians of medicine and historians of science.