208 PROF. O. REYNOLDS ON AN ELECTRICAL CORONA. 



the phenomena of the aurora and the direct effect of the 

 sun on the electricity of the earth's atmosphere, and on its 

 magnetism; there is, moreover, the observed connexion 

 between the sun-spots and terrestrial meteorology, as well 

 as the connexion between the planets and the sun-spots, 

 shown by Mr. De la Rue and Dr. Balfour Stewart. It must 

 be admitted that these are evident signs of some mutual 

 influence between the sun and the planetary bodies, which 

 is neither the result of gravity nor of heat. Almost all 

 these signs are of an electrical character; and some are 

 electricity itself; moreover electricity, or electric induction, 

 is the only other known " action at a distance " besides 

 gravity and heat. Is it not, then, probable that this 

 influence is electrical? Are we to reject an hypothesis 

 which explains some of these phenomena, and may explain 

 all, simply because we do not see any cause for the elec- 

 trical condition of the sun* — why the sun should be 

 charged with negative electricity ? 



Should we have discovered that the sun is hot if we had 

 waited to find out why it was so ? Surely it is sufficient to 

 say that there is no proof that it is not electrical. But we 

 may go further than this ; for, if we may compare large 

 bodies with small, then we may show a possible reason for 

 the sun's being electrified. When two particles of diffe- 

 rent metals approach or recede from each other, they 

 become electrified with opposite electricities. May not the 

 sun be approaching or leaving some other body of a diffe- 

 rent material ? I do not suggest this as a probable expla- 

 nation, but simply in answer to those who say that it is 

 absurd to suppose the sun can be electrified. 



* This paper was read before Section A of the British Association in 1871, 

 when these objections were raised. 



