48 TRANSACTIONS OF THE [DeC. 5 



The Bearing of Electrical Discharges on Solar Physics. 



[abstract.] 



A.. luJirect evidences favoring an electrical theory of the solar 

 corona. 



1. EviiJence^ obtained from the visiible spectrum of the corona. — 

 Tiie assumption that the visible coronal glow is due to electrical 

 disturbances in the coronal regions has just as much probability 

 in its favor as any other assumption. That part of the coroual 

 light which is reflected sunlight may be due to a decomposition 

 of the coronal vajjors produced by the action of the ultra-violet 

 light of the sun, or by the action of the electrical disturbances 

 in the coronal regions. 



2. Enidences ohlainec^ from the idtra-vioJet spectrum of the co- 

 rona. — These evidences seem to indicate that the maximum 

 energy of the coronal spectrum is near its violet end. If so, 

 this fact would speak very forcibly in favor of the assumption 

 that the coronal light is due to electrical disturbances in the 

 coronal regions. 



B. On the admini^Me causes which are capable of jiroducing elec- 

 trical disturbances in the coronal regions. 



These causes are shown to be the electrical oscillatory dis- 

 charges in the solar atmosphere, resulting from the electrical 

 tensions which are produced by the heterogeneous nature of 

 the solar atmosphere, by internal friction and possibly also by 

 chemical process. 



G. The effects of the electrical waves propagated through 

 interplanetary space are then discussed, especially those due to 

 the absorption of these waves by the gases which constitute the 

 solar corona. Various cases are considered, and it is pointed 

 out that all the various coronal forms can be explained in a sci- 

 entifically legitimate manner by the abovementioued absor]itioriS 

 of the electrical waves. Lines of laboratory' research capable of 

 throwing more light upon these evidences are then discnssed, 

 and the author concludes his remarks with a promise of exhibit- 

 ing very soon before the Astrouomical Section some experiments 

 which have a direct bearing upon the various questions dis- 

 cussed in the paper. 



Prof. Rees then referred briefly to the observations of Holmes' 

 comet made at Columbia College Observatory by himself and 

 by Mr. Jacoby and Mr. Monell. These observations will be 

 published in the AstronomicalJournal. He also gave an account 



