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Making natural knowledge?

I have been working with scientific objects throughout my entire professional career. First, as an instrument maker, I built scientific instruments and applied them in experimental set-ups for plasma physics research. For a period I also operated a group of magnetometers for registrations of terrestrial magnetism. Now, as an historian, I am using old instruments and reconstructions as sources in my studies of past scientific activities.
The history of magnetic inclination and declination plays an important role in the history of the Aurora Borealis. The connection between high auroral activity and rapid movements (declination) of the compass needle was described for the first time in 1747 by Olof Hiorter in Uppsala. During our visit in Florence with the Wandering Seminar, we saw this fine declination compass from ca. 1786, built according to descriptions by Charles-Augustin Coulomb (object 1). It is made from marble with a long, asymmetric and wire-suspended magnetic needle, and furnished with a small microscope for accurate detection of the needle's movement.
New designs of such instruments were developed during the eighteenth and nineteenth century, and around 1880 the instrument ‘stabilized’ in a model having a small magnet with a mirror suspended in a wire (object 2). To function, it had to be part of an experimental set-up consisting of a light-source emitting a beam to the mirror, and a rotating drum with photographic paper run by a clockwork. The light-beam was reflected by the mirror to the drum, and as the small suspended magnet vibrated due to the perturbations in the Earth’s magnetic field, its movements became recorded on the photographic paper. In the 1980s, I operated such instruments myself at the Auroral Observatory in Tromsø.
At the beginning of the twentieth century, Kristian Birkeland undertook an extended study of such ‘magnetograms’ in his work on the Aurora Borealis (see the Terrella). During the winter 1902-03, he had technicians hibernating on Spitzbergen and Novaya Semlja doing such recordings; undertakings which in fact were huge enterprises (expeditions) consisting of series of different elements. Planning, funding, employing crew members, procuring scientific equipment and supplies, arranging accommodation and transport, etc. were all necessary elements in the data collection. The declination compasses themselves (the magnetometers) were in this case only the link in the chain where the whole operation were connected to the natural phenomenon of interest, or came closest to it. Seen in retrospect, the operation of such instruments illustrates well the problem of whether natural phenomena can be described as ‘discoveries’ or as ‘constructions’. Since Hiorters meticulous registrations in the 1740s (he undertook more than 7000 systematic observations of the magnetic needle) to Birkelands freezing assistants in the Arctic in the early 1900s, the conditions, routines, behaviour and role of the data collector himself have been important ingredients in the production of magnetic measurements.