198 



MAGNETIC DISTUEBANCES AND AUROKA. 



July 27, 1903 



2.0 a.m. Isolated patches of diffused aurora 

 from N. to S.E., altitude 10 to 30. 



4.0 a.m. Streamers or rays from N. to S.E. ; 

 various heights, mean 40. 



The aurora was more or less visible all night, 

 and confined principally to N.E. ; average 

 altitude 20. 



At about 9.45 p.m. an unusual form of aurora 

 appeared. A band of light extended from due S. 

 to due N, passing round through E. Breadth of 

 band 5 and averaged 12 in altitude. Intensity 

 fairly strong in N. ... The display reached its 

 maximum brilliancy at about 9.50 p.m., and had 

 almost entirely disappeared at 10.10 p.m. A few 

 arrow-like beams were visible here and there just 

 above the band. 



July 28, 



2.0 a.m. Faint aurora diffused over the E., I 

 forming a narrow curtain and a few streamers 

 scattered irregularly. 



3.0 a.m. Fine display of aurora, involving the 

 whole heavens from N.W. by E. to S. Nothing 

 ever visible in S.W. Three fine compact curtains 

 in the E., one above the other, height of uppermost 

 approximately 60. Three more curtains, more 

 diffused, but bright and much folded, extended 

 from N.W. to zenith, where there were two large 

 bright luminous clouds. The rest of the area was 

 filled with more or less isolated streamers, small or 

 fragmentary curtains or clouds. All was constantly 

 changing . . . 



4.0 a.m. Only the remains of the above display 

 visible . . . 



(continued). 



V, which had been falling rather markedly since 

 0.35 a.m., rose about 20y between 1.55 and 

 2.5 a.m., and then diminished. There were 

 approximately equal to-and-fro movements in both 

 D and H, the turning-points occurring at about 

 1.55 a.m. D first diminished about 30' and then 

 increased, while H diminished about 20y and 

 then increased. 



From about 3.35 to 4.25 a.m. there was a deep 

 bay on the H curve ; the turning-point, which 

 answered to a minimum in H, occurred within a 

 few minutes of 4.0 a.m., but was beyond the limits 

 of registration. 



The D curve was not specially disturbed at 

 4.0 a.m., but there were minor oscillations on the 

 V curve. 



Between 9.20 and 9.30 p.m. V increased about 

 25y, and then remained nearly stationary until 

 about 9.42 p.m., when a further rapid rise ensued. 



Between 9.42 and 9.57 p.m. the increase was 

 about 80y. During the next 5 minutes V fell a 

 little, and then was nearly steady until after 

 10.20 p.m. 



There were sharp oscillations in D and H 

 between 9.45 and 10.0 p.m., but of no great 

 magnitude. 



1903. 



About 2.0 a.m. there were small oscillations on 

 the V trace. There was a deep bay on the D 

 curve, the turning-point, which answered to a 

 maximum, occurring about 1.45 a.m. Between 

 that hour and 2.20 a.m. D diminished about 70'. 

 There was a considerable movement in the H trace, 

 which remained beyond the limit of registration, 

 in the direction of H diminishing, from 1.40 to 

 2.15 a.m. 



Between 2.55 and 3.20 a.m. there were marked 

 oscillations in V, there being on the whole a 

 decrease of about 30y. Between 3.20 and 3.38 a.m. 

 there was a very rapid increase, amounting to 

 about HOy. The H trace went beyond the limit 

 of registration in the direction of H diminishing 

 about 3.15 a.m., but only for a few minutes. The 

 change preceding this was very rapid. 



