THE STORY OF NINETEENTH-CENTURY SCIENCE 



conjuring with the electric wire. Such magnetic storms 

 are curiously associated also with spots on the sun just 

 how no one has explained, though the fact itself is un- 

 questioned. Sun-spots, too, seem directly linked with 

 auroras, each of these phenomena passing through peri- 

 ods of greatest and least frequency in corresponding 

 cycles of about eleven years' duration. 



It was suspected a full century ago by Herschel that 

 the variations in the number of sun spots had a direct 

 effect upon terrestrial weather, and he attempted to 

 demonstrate it by using the price of wheat as a criterion 

 of climatic conditions, meantime making careful observa- 

 tion of the sun-spots. Nothing very definite came of his 

 efforts in this direction, the subject being far too complex 

 to be determined without long periods of observation. 

 Latterly, however, meteorologists, particularly in the 

 tropics, are disposed to think they find evidence of some 

 such connection between sun-spots and the weather as 

 Herschel suspected. Indeed, Mr. Meld rum declares that 

 there is a positive coincidence between periods of numer- 

 ous sun-spots and seasons of excessive rain in India. 



That some such connection does exist seems intrinsi- 

 cally probable. But the modern meteorologist, learning 

 wisdom of the past, is extremely cautious about ascribing 

 casual effects to astronomical phenomena. He finds it 

 hard to forget that until recently all manner of climatic 

 conditions were associated with phases of the moon ; 

 that not so very long ago showers of falling-stars were 

 considered ''prognostic" of certain kinds of weather; 

 and that the "equinoctial storm" had been accepted as 

 a verity by every one, until the unfeeling hand of statis- 

 tics banished it from the earth. 



Yet, on the other hand, it is easily within the possi- 



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