NO. 6.] 



SLEDGE-EXPEDITION. OBSERVATIONS 1895. 



113 



direction might be expected by reason of the increasing easterly declination. On the other hand 

 the Fram had a considerable westerly drift during the same days ; but from Mr. Nansen's obser- 

 vations of a different drift on both sides of an open channel, frequently made both before and 

 later on, it follows that the drift of the travellers can not be supposed to be the same as that 

 of the ship. For the observations taken by watch until the first determination of LT on April 2, 

 the effective course has been assumed as north. 



The index correction of the sextant was generally determined by means of the horizon; 

 in some cases when it was not determined, the adopted value has been added by the observer 

 as ( . . ?), where the dots stand for a number. 



All observations were taken by Nansen, Johansen noting the watch. 



For the last observation LT I was assumed = 5 h 55 m ; the first altitude of March 25 

 appears to have been taken somewhat after the culmination, and it was because the observer 

 had the same impression that the second altitude was taken. 



1895, March 29. Temperature - 36.5, Bar. 30.05 inches. 



Near noon, the following 4 altitudes were taken with the altazimuth, 2 in each position of 

 the instrument: 



Sun U. L. Vertical Circle 81 45'.5, 98 I'.O, 97 59'.0, 81 51'.5; 



then with the sextant, ind. corr. + 3', height of eye 14 feet: 



Watch II 6k 27m 118.5, Sun L. L. 7 12'. 



The first two observations with the altazimuth would give the true altitude of the Sun's 

 centre 7 44', the last two 7 40'; but no times having been noted, they only give the limit: 



N. Lat. ^ 85 33'. 



Applying the correction + 6t 7m to watch II, whose rate seems to have been insignificant, 

 the sextant observation would give 



N. Lat. 85 57- with fy = _ 0-00 9 

 At 



which is incompatible with the limit above. The difference seems too great to be explained by 

 an irregular elevation of the horizon; but whether there is an error of observation, or some 

 accident has occurred to watch II, cannot be settled, as II ran down two days after without any 

 comparison before the stopping. The observation would require a correction to II more than an 

 hour greater than that applied ; the possibility of a change of longitude to this extent, is excluded 

 by the following observations. 



1895, April 2 and 3. Bar. 30.61 in., Therm. - 31.5 C. 



The meridian altitude of the Sun L. L., measured on April 3 from the apparent horizon 

 with height of eye 16 feet, index correction 0', was 9 4', which gives 



N. Lat. 86" 4'. 



This observation was taken at the camping-place after a day's travelling, commencing 

 April 2 about 3 p.m. and ending early in the morning of April 3, including a rest for dinner 



15 



