6lO PHILOSOPHICAL TRANSACTIONS. [aNNO I67I. 



not in that catalogue were yet in the heavens; so we may well grant that some 

 of those that have been observed since have not appeared always. For besides 

 the stars that have been seen in the constellation of Cassiopea, in the neck of the 

 Whale, in the breast of the Swan, and in Serpentarius ; M. Cassini has discovered 

 many other small ones, * which may very well be presumed to be new. For 

 example, he has observed one of the fourth magnitude and two of the fifth in 

 Cassiopea, where it is certain they were not seen before, many astronomers hav- 

 ing exactly reckoned up the very smallest stars of that constellation, and yet 

 not one of them mentioned those three. He has discovered two others, towards 

 the beginning of the constellation of Eridanus, where we were sure they were 

 not about the end of the year l664, considering that this place of the heavens, 

 where passed the then appearing comet, was diligently beheld by many, who 

 perceived divers other small stars, without observing those two. He has also 

 observed, towards the arctic pole, four of the fifth or sixth magnitude, which 

 astronomers, that always have their eyes upon that place, would not have failed 

 to note, if they had there appeared before. 



IS] or are we to wonder at it, that we see now more stars in the heavens than 

 there appeared formerly, seeing there appeared some formerly which are seen no 

 more now. For M. Cassini has observed, that the star which Bayer puts near 

 that which he marked in the figure of Ursa Minor, appears no more; that that 

 -which is marked A in the figure of Andromeda has also disappeared; that in lieu 

 of that which is marked v at the knee of the same figure, there are two others 

 more northward; and that that which is noted g is very much diminished. The 

 star which Tycho places at the extremity of Andromeda's chain, and calls it of 

 the fourth magnitude, is now so small that one can scarce see it; and that which 

 is in his catalogue the 20th of the constellation of Pisces, is now no more seen ; 

 unless you will say, that it is gone down lower by four degrees, to the place 

 marked o in Bayer's figure. -j^ 



But we are not therefore presently to say, that the stars that have been lately 

 discovered were not in the heavens before, although they were not seen there. 



* Compare those, discovered by M. Hevelius, in No. 65, p. 528. 



f We may here notice an extract of a letter of April 30, l6"70, to the Royal Society from Signor 

 Montanari, professor of mathematics in Bononia. " I might announce to you many new things I 

 have observed in the heavens of late years j but one, which is very remarkable, is, tliat there have dis- 

 appeared two stars of the second magnitude, in die stern of tlie ship, marked ^ and y by Bayer, near 

 Canis Major, observed by myself and others, particularly on occasion of tlie comet in l66i. I know 

 not in what year these disappeared, but this is certain, that from April 10, l668, 1 have found no ap- 

 pearance of themj and that otliers near them of the fourth and fifth magnitude still remain. Many 

 other changes of the stars^ even more than a hundred, but less important, I have at times ob- 

 served, &c." 



