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VII. Obfervatio?2S of a fiew variable Star, In a Letter from 

 Edward Pigott, Efq. to Sir H. C. Euglefield, Bart.F. R, S, 

 and j^, S. 



Read December 23, 1784. 



D E A R s I R, 



FOR fome years pad 1 have been employed in verifying 

 all the flars fufpeOed to be variable, in order that here- 

 after we may know with certainty what to depend upon. This 

 undertaking, which is nearly completed, has already proved 

 of ufe in detecting many miftakes, and producing fome difco- 

 veries ; among which, the following is one of the mofl: im- 

 portant. September 10, 1784, I flril: perceived a change in 

 the brightnefs of the ftar vj Antinoi, and by a feries of obfer- 

 vations made ever fince, I find it lubjed: to a variation very 

 limilar to that of Algol, though not exadlly the fame in any 

 one particular. 



7] Antinoi, when brightefl:, is of the third or fourth magni-^ 

 tude, being between S and (3 Aquilas ; and at its leaft bright- 

 nefs of the fourth or fifth magnitude, it then being betweea 

 that of I Antinoi and ^ Aquilae ; therefore, its greatefl varia- 

 tion in brightnefs may be called about one magnitude ; and the 

 changes it undergoes, though probably not nicely afcertained 

 from fo few.obfervations, are nearly thefe :, 



4 At 



