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The development of geomagnetic research in the 19th century is discussed in detail. Beginning with the Göttingen Magnetic Society (Gauss-Weber), scientific activity developed under von Humboldt's influence and reached a peak during the First International Polar Year (1882--1883). This was a broad international co-operation, for which new instruments were constructed and new aspects of the geomagnetic studies were opened, including solar-terrestrial physics (Sun -- aurora -- Earth's atmosphere).
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Schröder et al. (2002) studied this question.
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