PART II. POLAR MAGNETIC PHKNOMENA AND TERRELLA EXPERIMENTS. CHAP. VI. 677 



In some spectrographic researches on prominences on the solar disc, Fox makes the following 

 tatement('): "Examination of all the H n (hydrogen) plates and the record of earlier observed whirls in 

 lie calcium vapours results in assigning the direction as counter-clockwise in the northern hemisphere 

 nd clockwise in the southern. This is in agreement with the demands of FAYK'S theory." 



In analogy with our experiments, these whirls should not be due to cyclones or whirlpools, as Faye 

 upposes, but to negative electric emission from certain centres of electric eruption. It should be remarked 

 lat as this electric emission is connected with calcium vapours and with hydrogen, it is to be expected 

 lat its velocity will not be nearly so great as that of light. 



Owing to the good experimental results, which already give certain promise of the attainment of a fult 

 nderstanding of the two above-mentioned important phenomena the vortex-formation and the apparenl 

 real capacity of the cathode-globe, I have begun to construct a vacuum-vessel of 1000 litres' capacity, with 

 eiling and floor of bronze, and glass sides of 50 mm. thickness. There have proved to be disadvantages 

 i having the floor and ceiling magnetisable (of steel) and in their not b"eing far enough from the polar 

 arts of the large cathode-globe. The magnetic cathode-globe is to be 40 centimetres in diameter, for 

 ischarges of 500 milliamperes at 15000 volts, which is the maximum delivery of my machine (see fig. 67). 

 : will be easily understood that in addition to the purely scientific reasons for doing this, I have also a 

 econdary object, which is to give myself the pleasure of seeing all these important experiments in the 

 lost brilliant form that it is possible for me to give them. 



131 The Worlds in the Universe. From the conceptions to which our experimental analogies 

 ;acl us, it is possible to form, in a natural manner, an interesting theory of the origin of the worlds, 

 "his theory differs from all earlier theories in that it assumes the existence of a universal directing 

 tree of electro-magnetic origin in addition to the force of gravitation, in order to explain the formation 

 aund the sun of planets which have almost circular orbits and are almost in the same plane of moons 

 nd rings about the planets, and of spiral and annular nebulae. Even the newly-discovered, most distant 

 loons of Jupiter and Saturn, with their retrograde revolution, do not place the theory in any doubtful 

 ght; on the contrary, the discovery would seem to predict that if planets are still discovered round the 

 in sufficiently far outside Neptune, they might also have a retrograde revolution. 



The fundamental assumption with which we shall start will correspond with one of the three above- 

 icntioned assumptions regarding the sun. For the sake of simplicity, we will assume, in conformity 

 ith case 3 above, that all suns in relation to space have an enormous negative electric tension, diffe- 

 nt for the different stars, but which, as regards order, might be somewhere about a milliard volts for 

 :ars of a class similar to our sun. 



In this way electric discharges will be produced, among them being disruptive discharges from com- 

 aratively small areas (spots). One might imagine that radiation from these will give rise to circular 

 .irrents in the star, parallel with the plane of the equator of the rotating central body, whereby the 

 intral body becomes magnetic. 



We can then begin, for instance, to seek for an explanation of the formation of spiral nebulae. 



POINCARK, at the conclusion of the preface to his book, 'Hypotheses Cosmogoniques', says : 



"Un fait qui frappe tout le monde, c'est la forme spirale de certaines n6buleuses; elle se rencontre 

 oaucoup trop souvent pour qu'on puisse penser qu'elle est due au hasard. On comprend combien est 

 icomplete toute th6orie cosmogonique qui en fait abstraction. Or aucune d'elles n'en rend compte d'une 

 laniere satisfaisante, et 1'explication que j'ai donn6 moi-meme un jour, par maniere de passe-temps, ne 

 aux pas mieux que les autres. Nous ne pouvons done terminer que par un point d'interrogation." 



(') Astrophys. Journ., November, 1908, p. 257. 



Birkeland. The Norwegian Aurora Polaris Expedition, 19021903. 8(1 



