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E. WALTER MAUNDER, F.R.A.S., ON 



of the Greenwich magnetic records, a storna was found to have 

 occurred in eight consecutive rotations when the sanae solar 

 longitude was on the centre of the disc, and no other magnetic 

 disturbances took place in the intervals between them. 



A little reflection showed what this implied. Lord Kelvin's 

 objection to the supposed connection between the two activities 

 as cause and effect was based on the assumption that the solar 

 action must, like its emanation of light and heat, be emitted 

 from all points of the solar surface, and be radiated equally in 

 all directions. This would involve an expenditure of energy 

 quite inadmissible. 



But the return of magnetic disturbances at the end of a com- 

 plete rotation of the sun showed that the solar action was not 

 radiative, but of an altogether different kind. Instead of coming 

 from every part of the sun's surface as is the case with its light 

 and heat, it proceeded only from restricted regions ; instead 

 of being radiated equally in all directions, it travelled to the 

 earth in certain defined directions. It was due, therefore, to the 

 emission from certain special areas of the sun of minute particles 

 shot out in narrow streanas, which, as they rose from certain 

 particular areas and were continually supplied from those same 

 areas, inevitably appeared in their effect to rotate with the 

 sun's rotation. Therefore as the sun, as seen from the earth, 

 appears to rotate in a little over 27 days, the magnetic disturb- 

 ances tended to be repeated at like intervals of time. The 

 streams of particles from the sun overtook the earth in its orbit, 

 and struck it on that arc of the earth's surface to which the 

 sun. was then setting. 



It was already known that particles are shot off from the 

 sun in this manner. Photographs of the corona during total 

 solar eclipses had shown straight rays, extending from the sun 

 in several directions, and in the eclipse of 1898, January 22, 

 Mrs. Maunder obtained a pair of very small photographs of the 

 corona on which no fewer than four of these long straight rays 

 were clearly seen. The longest of these was traced to a distance 

 of fully 6,000,000 miles. If, as is most likely, it was fore- 

 shortened in its presentation to us, then its actual length naust 

 have been so much the greater. 



It has been pointed out above that sunspots are very small as 

 compared with the sun, but very large as compared with the 

 earth, and that the influence of spots upon the earth, though 

 perceptible, is not of a pronounced and obvious nature. It 



