Terrestrial magnetism and the development of international collaboration in the early nineteenth century

The establishment of Gauss's and Weber's Magnetische Verein in 1834, and the British Government's support of Edward Sabine's ‘Magnetic Crusade’ in 1838, marked the opening of a new era in international geomagnetic research. However, the British and German efforts, although initiating an increase in the scale of investigations of the earth's field, were also the culmination of over half a century of activity by individuals and institutions in several countries. This article traces the growth of international cooperation in terrestrial magnetism from the late eighteenth century until the 1830s, and examines the change in leadership in the field from France to Britain and Germany. The transition from individual to government-backed collaboration is described, and also the role of Alexander von Humboldt as an organiser of geomagnetic research and author of a cosmical approach to earth magnetism as one of a number of related ‘telluric’ forces.