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During the Norwegian Antarctic Research Expedition 1978–79, direct measurements of oscillations were carried out on 15 icebergs using a tiltmeter with an accuracy of ± 10 μrad. The amplitude of the oscillations varied from zero to about 103 μrad. The zero amplitude indicates that the berg was grounded and this was confirmed by echo-sounding from the ship. The observed oscillation periods ranged from 16 to 50 s. The observed oscillation periods and the calculated values based on the dimensions and mean density of the bergs were compared and the results are discussed. The flexure of the berg was measured with a theodolite and stakes. Relative movements exceeding the accuracy of the system (1 mm over 1 km distance) were not observed.