The author makes an analysis of clinical case histories drawn up by students under thé direction of Juan Bautista Peset y Vidal (1821-1885). One discerns the commencement of «laboratory medicine» and the mastering of the anatomo-clinical mentality. The first part consists of a -study of the statistics that appear in the case histories, and the second part deals with their contents, placing them in á certain age and within the scope of the medical knowledge of that time, for the director is considered, a figure of importance in' these areas.El autor hace un análisis de historias clínicas realizadas por estudiantes bajo la dirección de Juan Bautista Peset y Vidal (1821-1885).'Se percibe el inicio de la «medicina de laboratorio» y superación d...