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epochs of maximum than those of minimum solar 

 activity. 



On the 10th April last, several small groups of 

 sunspots were photographed at the Mauritius Obser- 

 vatory, and on the 11th another group consisting of 

 rather small spots surrounded by faculce was observed 

 on the eastern limb. At a. m. on the 13th, another 

 and remarkable large group, which must have 

 appeared on the eastern limb on the 12th, extended 

 over several degrees of latitude. The space between 

 this last group and the preceding one of the 11th was 

 more or less covered with faculce. In the course 

 of its apparent progress westward, the second group, 

 that of the 13th, widened out as the effect of fore- 

 shortening descreased, and showed several large 

 nuclei embedded in one immense penumbra. The first 

 group (that of the 11th) varied little until the 16th, 

 but between the 16th and 17th it increased greatly, 

 and again on the 20th; there having been two 

 distinct solar outbursts. On the 21st, both groups 

 were nearly of the same magnitude. The first group 

 passed off the sun's visible disc on the 23rd and the 

 second on the 25th. At one time or another from the 

 15th to the 21st, the' area of each of those two groups 

 exceeded 2,400 millions of square miles, and they 

 could easily be seen, through stained glass, by the 

 naked eye. From the 14th to the 21st, the total area 

 of all the sunspots was unusually great, exceeding on 

 the 17th fully 5,000 millious of square miles, or 26 



