THE EARTH A MAGNET. 



35 



tion will naturally arise, has the sun anything to do 

 with magnetic storms ? We have clear evidence that 

 he has. 



On the 1st of September, 1859, Messrs. Carrington 

 and Hodgson were observing the sun, one at Oxford 

 and the other in London. Their scrutiny was directed 

 to certain large spots which, at that time, marked the 

 sun's face. Suddenly a bright light was seen by each 

 observer to break out on the sun's surface and to travel, 

 slowly in appearance, but in reality at the rate of 

 about 7,000 miles in a minute, across a part of the 

 solar disc. Now it was found afterwards that the self- 

 registering magnetic instruments at Kew had made at 

 that very instant a strongly marked jerk. It was 

 learned that at that moment a magnetic storm pre- 

 vailed at the West Indies, in South America, and in 

 Australia. The signalmen in the telegraph stations at 

 Washington and Philadelphia received strong electric 

 shocks ; the pen of Bain's telegraph was followed by a 

 flame of fire ; and in Norway the telegraphic ma- 

 chinery was set on fire. At night great auroras were 

 seen in both hemispheres. It is impossible not to con- 

 nect these startling magnetic indications with the re- 

 markable appearance observed upon the sun's disc. 



But there is other evidence. Magnetic storms 

 prevail more commonly in some years than in others. 

 In those years in which they occur most frequently, 

 it is found that the ordinary oscillations of the mag- 

 netic needle are more extensive than usual. Now 

 when these peculiarities had been noticed for many 



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