Edward Sabine and the “Magnetic Crusade”

Abstract

The last decades of the nineteenth century witnessed a number of attempts at international cooperation in cartography, including the establishment of the Greenwich Meridian as the standard for both time and longitude, and Penck’s proposal for the International Map of the World. What is less well known was an earlier cooperative venture, the so called ‘Magnetic Crusade’. At a time when maritime navigation was still dependent on the magnetic compass, it was important to know the variations in magnetic declination. Edward Sabine was charged with running the Magnetic Department and established an international group of collaborators, including important scientists such as Gauss, to collect data from around the world. Sabine was also able to use the network of British colonies and their observatories and voyages of exploration to polar regions, including the Franklin relief missions, to collect data. This chapter will explore the work of Sabine’s department, its network of collaborators, the attempts made to impose standards on the measurements made, and the maps it produced.