TERRESTRIAL MAGNETISM. 129 



many nights, I always found the easternmost turning-point 

 of the needle, in the summer as in the winter months, 

 between 19| h. and 20 h. ; being very slightly, ( 155 ) if it 

 might be said to be at all, accelerated, by the earlier time ot 

 sunrise in the summer. 



In the high northern latitudes, near or within the arctic 

 circle, the regularity of the horary variation has been as 

 yet but imperfectly made out, although we possess a number 

 of very exact observations. In Iceland, Lottin, in the 

 French scientific expedition of the 'Lilloise' in 1836, was 

 almost afraid (considering the local influence of rocks, and 

 the frequency of Auroras) to derive any determinate results 

 in respect to the turning hours, either from his own 

 extensive and laborious observations, or from the earlier 

 ones (1786) of the meritorious Lowenorn. On the whole, at 

 Reikiavik, in Iceland, lat. 64 8', as well as at Godthaab on 

 the Greenland coast according to the missionary Genge's 

 observations, the minimum of westerly declination appears 

 to fall almost as in the middle latitudes, at 21 h. or 22 h., 

 but the maximum not until 9 h. or 10 h. in the evening. ( 156 ) 

 Further to the north, at Hammerfest, in Finmarken, in 

 lat. 70 40', Sabine found the march of the declination 

 tolerably regular, ( 157 ) and similar to that in the south of 

 Norway and in Germany; westerly minimum at 21 h., 

 westerly maximum at 1J h.; but he found it very different 

 in Spitzbergen in lat. 79 50 , where the corresponding 

 turning hours were 18 h. and 7J h. For the Arctic Islands 

 north of America, we have at Port Bowen, on the eastern 

 side of Prince Regent' s Inlet (lat. 73 14'), from Captain 

 Parry's third voyage (1825), a fine series of five months' 

 consecutive observations by Lieuts. Foster and James Ross: 



YOL. IV. K 



