[ :V^AR1ABLE STAR5, £77 



s^volution of 74 days, as required ; for a view of a Ihort Inter- 

 val, for the prefent let that of 56 days be taken betyveei^ Auguft 

 21ft and Odober 16th 1801. (See Table X.) , '' 



bth View. 



The leaft brightnefs or miniminn \t reprefented by fig. 6, Lcaft brightncf», 

 when the bright fpots^^ and x at each extremity of the equa- 

 torial diameter are mutually but juft in light and a minute one, 

 r alone on its furface preceding j/ by 6 days motion: n n, are 

 other middling iized fpols near x, but preceding it; they 

 cannot for the prefent be feen, being on the oppofite or bright 

 hemifphere. The fpot x during the liars revolution having 

 loft its light, and r being confiderably increafed, the next 

 mimnum will be between n n and 7-, (inftead of jr andj^.) See 

 fig. 7 ; and by the retiring of" n n the diminution of the ftar's' 

 light will continue to take place only until the re-appearance 

 of r, at the place where j/ was, which being 6 days fooner than 

 the former polition, (See fig. 6,) reduces the rotation to 56 

 days, AU the foregoing views are from unconnedcd periods, 

 where only the ultimate returns of each appearance have been 

 attended to ; but now, I (hall examine a long interval with 

 many intermediate changes, that between June 18th, and 

 September 17th 1796, wherein are included the moft intricate 

 irregularities and viciflitudes : thefe obl'ervations are already- 

 pointed at full length in the Philofophical Tranfaciions for 

 1797, and therefore can at any time be infpeded : indeed, I 

 then little tliought they would ever become of further ufe, but 

 that of ftating fads, to which, however, I have always been 

 very partial, and particularly fo, after having experienced the 

 advantage of Maraldi's printed obfervations on the variable 

 ftar in Hydra, as it was partly by them that I afcertained the 

 periodical returns of brightnefs of that ftar, and which flattered 

 me the more, as Maraldi himfelf had been lefs fuccefsful 

 in the attempt; See Phil. Trans, for 1786. Yet in the 

 prefent Paper I have omitted all fuch details, being aware 

 they might be thought too voluminious, but hope at fome 

 future time the Society will honour them with a place in their 

 ^brary. 



The firft iketch, Plate XlV.reprefents, for June 1 3, 1796, the 

 comparative fize of the bright fpots fuppofed to furround the 

 lter> but here extended at full length ; the next eight following 



are 



