PART II. POLAR MAGNETIC PHENOMENA AND TEKKELLA EXPERIMENTS. CHAP. II. 449 



formed of ordinary cathode rays, about 5X IoH if we assume/? rays with a velocity of 2.59 X io' cm.sec.~'. 

 It is, however, reasonable to suppose as we shall show in describing the terella experiments in a sub- 

 sequent chapter that the rays in this case are considerably stiffer than these. If we assume a stiffness 

 10 times as great as the stiffest rays, or answering to UQ = 7 X IO > we obtain an amount of energy 

 of about io 1:J h. p.. From this we have inferred backwards and proved that we come, by assumptions 

 which are still indeed rather arbitrary, but not unreasonable, to values for the amount of energy emitted 

 from the surface of the sun in the form of corpuscular rays, that are as great as those of the energy 

 emitted in the form of light and heat. It does not therefore seem improbable that the disintegration of 

 the sun's matter which is undoubtedly taking place, and which must be assumed to be the cause of the 

 corpuscular rays observed, would be great enough to account for the emission of light and heat from the sun. 



A POSSIBLE CONNECTION BETWEEN MAGNETIC AND METEOROLOGIC PHENOMENA. 



93. If the view we have maintained is correct, namely, that the magnetic storms are due to cor- 

 puscular rays that are drawn in in zones round the magnetic poles, where they pass directly down into 

 the athmosphere of the earth, it is clear that these rays, especially in the upper strata of the atmosphere, 

 must be assumed to produce a strong ionisation in the air. In our expedition of 1902 & 3, atmospheric- 

 electrical measurements were made, which will be gone into later on ; but it may be remarked here, that 

 the result of these measurements showed that the "Zerstreuung" of the air at those stations averaged 

 about twice as much as in Christiania, indicating that the air up there is considerably more ionised than in 

 lower latitudes. In an expedition which I made, in company with my assistant, Mr. KROGNESS, to Kaafjord 

 at the time when Halley's comet crossed the sun's disc in May 1910, I had an opportunity of studying 

 this matter more closely. 



Instead of, as before, making the measurements at places that are at no great height above sea- 

 level, 1 on this occasion investigated it at my old aurora-observatory on the top of Haldde Mountain, 

 about 910 metres above the sea. Here there proved to be sometimes tremendous variations. On the 

 2oth May, for instance, values were found that went up to about 500 times the normal. Unfortunately the 

 attempt was interrupted in the middle of these measurements; but I had an opportunity of making 

 insulation-tests twice at that time, which proved there was no perceptible leakage. If we can demonstrate 

 this circumstance with certainty, we presumably have before us a phenomenon that is closely connected 

 with the peculiar light-phenomena that LEMSTROM discovered in 1882 & 3 on a mountain-top at Sodankyla. 



There is no doubt that such strong ionisations will have a very great influence upon atmospheric 

 conditions, especially upon the formation of clouds, and must thus be assumed to be a meteorological 

 factor of no small importance, especially for the districts in the vicinity of the auroral zone. I am of 

 the opinion that this is a very important connecting link between terrestrial-magnetic and meteorological 

 phenomena. I have therefore recently submitted to the Norwegian State authorities, a suggestion that a 

 permanent up-to-date-magnetic-meteorological observatory be established upon the top of Haldde, for the 

 purpose, if possible, of throwing light upon these interesting and meteorologically important matters. 



There was another phenomenon, striking examples of which we had the opportunity of seeing on 

 this expedition in May, 1910, namely, the formation of what may be called auroral clouds. In addition 

 to the usual polar bands, which in a clear sky, could very often be observed in the form of several 

 evenly luminous arcs, of which, however one was especially conspicuous, exactly similar to parallel auroral 

 arcs, we very frequently found formations of cirrus clouds, which exhibited the most perfect argreement 

 with various auroral formations. Several times we had capital examples of the manner in which such 

 clouds are formed, how drapery-formations appeared in a short time, exactly in the same manner as an 

 auroral drapery. The first observer, who has called attention to this very interesting fact seems to be 



