1915- No. 5- ROALD Amundsen's ANTARCTIC expedition: METEOROLOGY. 49 



The second deviation occurred on the 6^'^ — 7*'' January, when the 

 Expedition was descending from the »Butchers« to the Barrier taking a 

 more direct way than when ascending. The positions have been compu- 

 ted by means of the notes in the Table of courses and distances, and 

 controlled by Capt. Amundsen's description of the voyaged 



The latitude and longitude of the stations where meteorological obser- 

 vations were made I have worked out by means of Capt. Amundsen's 

 sextant observations, his courses and registered distances, and Mr, Sverre 

 Hassel's Table of the hours of starting and camping. The position of the 

 intermediate stations between the camps has been found by interpolation 

 and calculated from the number of hours of travel from one camp to the 

 Station, and from the latter to the next camp. The distances read by the 

 sledge-meters were always checked, during the journey to the Pole, by 

 the latitudes observed with the sextant. From the Pole to the »Butchers« 

 on the Plateau northwards, the distances read had to be reduced in the 

 proportion of 100 to 90 in order to agree with the distances between the 

 camps found by observed latitudes. 



The mean error of latitudes may be ± 2'. To judge from the ob- 

 servations in latitude 89*^ 58' the latitudes may be 2' too high. The mean 

 error of the longitudes may be of the same order, measured on an arc of a 

 great circle. As one degre of longitude in the latitude of Framheim (78° 

 38') corresponds with o'^,25 or 15' of a great circle, and to less in higher 

 latitudes, it is quite sufficient to give the longitudes in tenths of a degree. 



II. Meteorological Observations. 



I. Temperature of the Air. 



On the excursion in September, 191 1, to the depot in lat. 80°, the 

 temperature was observed with the toluol sling-thermometer Küchler No, 

 895, centigrade. The corrections were found at the Meteorological Insti- 

 tute in Christiania to be — o".7 at o^ and -(- 0*^.2 at — 20^. The zero 

 point was verified in August at Framheim. 



On the journey to the Pole and back, the temperature was observed 

 with the same thermometer No. 895 from the 20*^^ October to the 17** 

 November, Afterwards the toluol sling-thermometer Kûchler No. 889, 

 centigrade, was observed from the 17*^ November 1911, 9 p. m., to the 

 25*'^ January 10 p. m. The corrections found in Christiania were o^.o at 



^ The South Pole, II. pp. 155—157. 



Vid.-Selsk. Skrifter. L M.-N. Kl. 1915. No. 5 



