1923- ^•'o. I o. DISTRIBUTION OF MATTER IN THE ATMOSPHERE. 



Probably this tapping must be prevented in some way and counter- 

 acted by some other solar process. The following possibilities naturally 

 suggest themselves: 

 1 1 The ions at the very low temperature might form big clusters consist- 

 ing of hundreds or thousands of molecules. 

 2 1 The earth might be supplied with a sufficient negative charge through 

 direct radiation of negative electrons from the sun to balance the loss 

 through photo-electric action. If there is a balancing process of this 

 kind the electric force might be maintained at less than 1 0~ el. st units. 

 31 The Nitrogen which is lost through photo-electric effect is balanced 

 through a supply of Nitrogen from the sun. In this case the upj)er 

 strata would not be in a state of statistical equilibrum. We could not 

 apply our differential equation for the distribution of matter. The higher 

 strata would be in a stationar\- state determined by two processes that 

 are kept in balance. 



The assumption that the higher strata constandy receive gas from the 

 sun is a rather suggestive idea, and if this matter was Nitrogen we should 

 natiiralh- have to assume that the corona of the sun contained Nitrogen, 

 and this would suggest that the coronal line of the sun should be a Nitrogen 

 line emitted under physical conditions present in the corona, where perhaps 

 N is in a highly charged state. 



Further the question arises, how the Nitrogen gets down into the 

 atmosphere. Here again it might be naturally suggested that the Nitrogen 

 formed the rays that produce the aurora borealis. In previous papers' 

 I have shown that the rays producing the aurorae must have a magnetic 

 deflectibility greater than a certain quantity, and this will also give a certain 

 upper limit to the penetrating power of the ra\-s, and this limit of penetrat- 



E 



ing power will decrease with the quantitv — where E is the charge, ;// the 



■ /// 



mass of a ray corpuscule. 



With a distribution of matter calculated on the assumption that the 

 temperature above 10 km. was 220" Abs. it was only electron rays that 

 gave a sufficient penetrating power. Even if only Nitrogen was present 

 in the auroral region, the amount of matter above 100 km. would be so 

 large that even hydrogen rays were excluded. — Now the spectral analysis 

 has shown that Nitrogen is a predominant component throughout the auroral 

 region, and if only Nitrogen is present, and if we suppose the temperature 

 to be lower than 220", the amount of matter above 100 km. might be so 

 small that rays with carriers of atomic order might combine a sufficient 

 magnetic deflectibility with a sufficient penetrating power to reach within a 

 distance of 100 km. from the ground. 



5. e. g. Phil. Mag. 42, p. 79. 



