160 cosaios 



aiscovered by MaralJi between J6 54 and 1709, their existence is morw 

 than questionable, they can not be introduced in our #.\*esent list. 

 (Jacques Cassini, Elimens (VAstron., p. 73-77 ; Delambre, Hist. d» 

 VAstr. Mod., t. ii., p. 780.) 



{v) One hundred and seventy-eight years elapsed after the appear- 

 ance of the new star in Vulpes without a similar phenomenon having 

 oocm-red, although in this long interval the heavens were most care- 

 fully explored, and its stars counted, by the aid of a more dihgent use 

 of telescopes and by comparison with more correct catalogues of the 

 stars. On the 28. h of April, 1848, at Mr. Bishop's i^rivate observatory 

 (South Villa, Regent's Park), Hind made the important discovery of a 

 new reddish-yellow star of the fifth magnitude in Ophiuchus (II. A. IG^ 

 50' 59" S. Decl. 12° 39' IG", for 1848). In the case of no other new 

 star have the novelty of the phenomenon and the invariability of its po- 

 sition been demonstrated with greater precision. At the present time 

 (1850) it is scarcely of the eleventh magnitude, and, according to Lich 

 tenberger's accurate observations, it will most likely soon disappear. 

 {Notices of the Astr. Soc, vol. viii , p. 146 and 155-158.) 



The above list of new stars, which, within the last two 

 thousand years, have suddenly appeared and again disap- 

 peared, is probacy more complete than any before given, and 

 may justify a few general remarks. "We may distinguish three 

 classes : new stars which suddenly shine forth, and then, after 

 a longer or shorter time, disappear ; stars whose brightness is 

 subject to a periodical variability, which has been already 

 determined ; and stars, like 7] Argus, which suddenly exhib- 

 it an unusual increase of brilliancy, the variations of which 

 are still undetermined. All these phenomena are, most prpb- 

 ably, intrinsically related to each other. The new star in 

 Cygnus (1600), which, after its total disappearance (at least 

 to the naked eye), again appeared and continued as a star of 

 the sixth magnitude, leads us to. infer the affinity of the two 

 first kinds of celestial phenomena. The celebrated star dis- 

 covered by Tycho Brahe in Cassiopeia in 1572 was consid- 

 ered, even while it was still shining, to be identical with the 

 new star of 945 and 12G4. The period of 300 years which 

 Goodricke conjectured, has been reduced by Keill and Pigott 

 to 150 years. The iiartial intervals of the actual phenom- 

 ena, which perhaps are not very numerically accurate, amount 

 to 319 and 308 years. Arago=^ has pointed out the great 

 improbability that Tycho Brahe's star of 1572 belongs to 

 those which are periodically 'variable. Nothing, as yet, 

 «j5ems to justify us in regarding all new stars as variable ia 

 long periods, which from their very length have remained 

 unknown to us. If, for instance, the self-luminosity of alj 

 tiic suns of the firmament is the rcsu t of an electro-mag' 



* Arago, Annual re po7ir 1813 p. 332- 



