8 AKSEL S. STEEN. TERRESTRIAL MAGNETISM. [NORW. POL. EXP. 



she was, and the following day, the 16th October, an inclination determi- 

 nation was taken out on the ice under the open sky. On account of the 

 screwing, the tent could not be put up again until February 10th, 1894, and 

 therefore all magnetic observations in the interval were made under the open 

 sky on the ice, at a distance of about 80 metres from the ship. After this 

 the tent was used from the 10th February until the 9th November, 1894, when 

 the apparatus was transported into a snow hut erected for the purpose, and 

 situated on the port side, about 100 paces from the vessel. In June, 1895, 

 the tent was again taken into use to escape from the effect of the sun's 

 rays. Later on -- September 26th, 1895 a new observatory was erected, 

 this time of blocks of ice, on the starboard side of the ship, at a distance of 

 135 paces straight out from her. On June 22nd, 1896, this ice observatory 

 fell down, and the last two series of observations, the 7th and 8th July, 

 1896, were therefore taken under the open sky. The distance of the obser- 

 vation-place from the ship was always so great that its iron could not be 

 supposed to have exerted any disturbing influence upon the magnets of the 

 apparatus. 



From the 12th January to June, 1895, an ice house, erected between 

 the vessel and the magnetic snow hut, was employed as a smithy; the 

 distance between the outer walls of the ice house and the snow hut was 

 55 paces. There was a forge in the smithy and an anvil, and now and then 

 there were other iron things, but never in large quantities, as the store of 

 materials was always on board, and only what was being worked upon was 

 taken to the smithy. It may therefore be assumed that also the proximity 

 of the smithy had no disturbing effect upon the magnetic observations. 



The wooden stand belonging to the apparatus was employed as a pedestal 

 for the magnetic instrument until the ice observatory was taken into use on 

 September 26th, 1895. The vibration-box, however, was placed, until May 

 24th, 1895, upon a stone slab frozen into the ice. The Cardan suspending 

 apparatus of the stand with counter-balance was of course not employed, 

 but was kept screwed fast all the time. The stand was therefore quite 

 firm, as the points of its legs rested immediately on the ice. It some- 

 times happened, however, that the effect of the sun was so great, that 

 the ice melted a little, so that the stand became a little oblique. This was 

 overcome by placing pieces of board under the legs. When the ice obser- 



