VOL. v.] PHILOSOPHICAL TRANSACTIONS. S^Q 



though I must have seen it, had it then been there. So that it hence appears 

 certain, that in the years 1660 and 1661 this star was not yet visible: it also 

 clearly appears, from Bayer s Uranomctria, that this new star did not appear in 

 1603 ; consequently not to Tycho, and mQch less to Hipparchus. For Bayer 

 would have perceived and inserted a star of that magnitude, since he describes 

 one of the sixth magnitude not far from it ; as may be seen in his constellation 

 of the Swan. Perhaps you may think this star of Bayer's is the same as my 

 new star ; and that, as he did not observe the stars with proper instruments, 

 so he might easily err by a degree or two from the true place. But this cannot 

 be allowed, since that small star still continues in the same place where Bayer 

 has set it, and is still seen a star of the 6th magnitude as he observed it. For, 

 as I have lately found, it is distant from Pegasus's mouth 32° 39' O", and from 

 his right knee 39° 23' A5" ; from hence its longitude comes out 6' 28" of ;rr, 

 and its latitude 46° ll' \A" north, in July 1670. But the new star is distant 

 from the mouth of Pegasus 32° 3l' 25", and from his right knee 38° 18' 50"; 

 from which distances its longitude is found to be 1° 52' lQ" c:z, and latitude 

 47° 25' 22'' north. So that this new star is evidently different from that of the 

 sixth magnitude observed by Bayer, though these two are not above two de- 

 grees distant from each other. And, from what is above said, it is also mani- 

 fest, that this new star did not shine among the other stars, either in the year 

 1603 or 1660. 



When I first observed it, it was not inferior in brightness to the star in the 

 breast of the Eagle, except that its light was a little more obtuse. As to its 

 situation, in respect of the other stars, it was placed in a right line with that 

 in the bend of the Swan's upper wing, and that in the shoulder of the Eagle ; 

 as also with the bright star of the Harp, and that in the rhombus of the Dol- 

 phin, which is the more northern of the middle ones. It made an equilateral 

 triangle with those in the head and back of the Swan. 



It however wonderfully decreased in the month of September, so that by the 

 14th of October it could not be observed at all with an instrument ; as ap- 

 pears by a future letter from Hevelius. 



The Observation on SaturrHs Ring in the same Letter. 



The telescope of 50 feet long, which you lately sent me, showed the face of 

 Saturn very distinctly, though the moon was up, the 26th of August 1670, 

 when it and the ring appeared rather long on both sides. The appearance was very- 

 different from that seen by you, and by M. Huygens, in 1666, and also by 

 the Paris observers in 1668. For the ring which encompasses Saturn was now 



VOL. I. 3 X 



