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the eastern limb of the sun, and was then a fine spot of not 

 less than the 3rd magnitude, and, after undergoing many- 

 considerable changes of form and structure, was finally- 

 observed very near the western limb, on the 21st of June, as 

 a spot of only the 9th or UJ magnitude, and from its previous 

 rate of decrease it is probable that it would become entirely 

 extinct in four or five days afterwards. Its duration, there- 

 fore, would not be less than 70 days, and it thus affords a 

 striking instance of the fact that frequent and extensive 

 changes of form and structure do not necessarily tend to 

 produce an early extinction of a spot. Between the 20th of 

 April, at 5h. I3m. G. M. T., and the 15th of June, at 

 5h. 30m., it moved through 783*3 degrees of longitude, or at 

 the rate of one sideral revolution in 25*74 days. On April 

 20th its heliographical latitude was 14° IV N., and on June 

 15th 14" 2' N. These results indicate a direction and rate 

 of drift which agree very nearly with the results which Mr. 

 Carrington has obtained for other spots in and near the same 

 parallel of latitude. 



