Magnetic observations in Spitzbergen in 1927

Abstract

The following observations were made by the writer of this article while a member of a Cambridge University expedition to Edge Island, the southeast member of the Spitzbergen group, in July and August 1927. The instruments used were a Kew pattern unifilar magnetometer, by Dover, Charlton (No. 161), a 3‐inch theodolite (used in some of the declination observations), and a chronometer which was checked by wireless time‐signals.Values of horizontal force were observed at six stations grouped round Stor Fiord, three on the islands and three on the mainland of Spitzbergen. The procedure adopted in every case was to perform successively vibration, deflection (30 cm.), deflection (40 cm.), deflection (30 cm.), and vibration experiments. Before leaving England the instrument was compared with the standard instruments at Abinger and a satisfactory agreement obtained. The declination was observed at seven separate stations, usually at intervals whenever convenient during the horizontal‐force experiment. Very little meaning can be attached to a single observation of declination in these latitudes, but by taking observations over two hours on a quiet day a mean value can be found. On very quiet days the needle may not move through more than three or four minutes of arc during two hours. The Sun was used for all azimuths, which were sometimes determined with the theodolite and sometimes with the magnetometer‐attachment.