[The professor and his student. The correspondence between Lorenz Heister and Christoph Jacob Trew].

Letters were the central medium of communication in the medical scientific community of the 18th century. Professional as well as personal relationships were established among the various correspondents. These relationships constituted the smallest units of communication which contributed to the regional and international scientific network of the Republic of Letters. A correspondence that grew out of a trusted teacher-student relationship could gain an especially intense character both intellectually and personally. This contribution offers an analysis of an example of just such a correspondence. Lorenz Heister (1683--1758), medical professor at the universities of Altdorf and Helmstedt, and his disciple, Christoph Jacob Trew (1695--1769), who became a renowned physician and natural scientist in Nuremberg, communicated in letters to one another over a span of almost forty years. Their correspondence started as a rather asymmetrical dialogue. Over time, however, Heister and Trew came to meet as equals in almost every field of their competence. Their letters reveal a broad spectrum of scientific, organisational, professional, medical and personal issues which formed the basis of a stable and lasting learned correspondence in the age of Enlightenment.