ELISHA MITCHELL SCIENTIFIC JOURNAL 25 



The other group — the third in order of these extensive dis- 

 turbances — was seen near the east limb Nov. 4th. Next day, 

 when more fully in view, it showed four very large spots with 

 15 smaller ones clustered about them. Its area exceeded that 

 of its immediate predecessor and its changes in form were 

 more surprising-. 



These three great groups, in view during the past thirty 

 days, had a total area more than 40 times the surface of our 

 earth. 



They amply furnish the element of size, as the Jul}' sun- 

 spots gave that of number. 



Number and size of spots indicate growing solar distur- 

 bance, and evidence unmistakably an approaching sunspot 

 maximum 



The period from one maximum to the next being about 11 

 years, we may expect the one now approaching to culminate 

 in or near the year 1904 — next year. 



It is not intended in this brief paper to discuss the many- 

 sided subject of sunspots; still less to even question profundi- 

 ties of the sun's constitution, or to consider the sources of its 

 seemingly exhaustless energy. 



I add, however, a single suggestion as to the nature of sun- 

 spots. 



They are often referred to as furious solar storms or cy- 

 clones. Unquestionably, in spot areas the surface material is 

 tossed and torn asunder and adjacent glistening facula? con- 

 sist of solar matter thrown into wildly irregular ranges piled 

 many times mountain high. 



But can there be at the sun's fiercely hot surface any such 

 difference of temperature as is essential to movements in any- 

 wise analogous to storms terestrial? 



Moreover we note on the sun a fairly sharp boundary be- 

 tween the dark disturbed areas and the adjoining bright re- 

 gions; while here, on the earth, there is a gradual transition 

 from regions of storm to regions of calm. 



Again, storms sweep the earth's surface; but visible mo- 



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