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Hansteen's magnetometer and the origin of the magnetic crusade

Published online by Cambridge University Press:  07 November 2013

VIDAR ENEBAKK*
Affiliation:
Norwegian Museum of Science and Technology, Kjelsåsveien 143, 0491 Oslo, Norway. Email: vidar.enebakk@tekniskmuseum.no.

Abstract

In the early nineteenth century, Norwegian mathematician and astronomer Christopher Hansteen (1784–1873) contributed significantly to international collaboration in the study of terrestrial magnetism. In particular, Hansteen was influential in the origin and orientation of the magnetic lobby in Britain, a campaign which resulted in a global network of fixed geomagnetic observatories. In retrospect, however, his contribution was diminished, because his four-pole theory in Untersuchungen der Magnetismus der Erde (1819) was ultimately refuted by Carl Friedrich Gauss in Allgemeine Theorie des Erdmagnetismus (1839). Yet Hansteen's main contribution was practical rather than theoretical. His major impact was related to the circulation of his instruments and techniques. From the mid-1820s, ‘Hansteen's magnetometer’ was distributed all over the British Isles and throughout the international scientific community devoted to studying terrestrial magnetism. Thus in the decades before the magnetic crusade, Hansteen had established an international system of observation, standardization and representation based on measurements with his small and portable magnetometers.

Type
Research Article
Copyright
Copyright © British Society for the History of Science 2013 

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