38 cosmos. 



happens in using the telescope. Three of this number were 

 almost in contact with one another, and four of them shone 

 as if through a mist, so that the space around them, having 

 the form drawn in the appended figure, appeared much bright- 

 er than the rest of the sky, which was perfectly clear, and 

 looked almost black. This appearance looked, therefoie, al- 

 most as if there were a hiatus or interruption. I have fre- 

 quently observed this phenomenon, and up to the present time 

 as always unchanged in form ; whence it would appear that 

 this marvelous object, be its nature what it may, is very 

 probably permanently situated at this spot. I never observed 

 any thing similar to this appearance in the other fixed stars." 

 (The nebulous spot in Andromeda, described fifty-four years 

 earlier by Simon Marius, must therefore either have been un- 

 known to him, or did not attract his attention.) That which 

 has usually been regarded as nebulous matter, adds Huygens, 

 " even the Milky Way, when seen through telescopes, exhib- 

 its nothing nebulous, and is nothing more than a multitude 

 of stars, thronged together in clusters. " # The animation of 



* " Ex his autem tres illae pene inter se contiguae stellse, cumque his 

 aliae quatuor, velut trans nebulam lucebant : ita ut spatium circa ip- 

 sas, qua forma hie couspicitur, multo illustrius appareret reliquo ornni 

 coelo ; quod cum apprime serenum esset ac cerneretur nigerrimum, ve- 

 lut hiatu quodam interruptum videbatur, per quem in plagam magis lu- 

 cidam esset prospectus. Idem vero in hanc usque diem nihil immutata 

 facie sa?pius atque eodem loco conspexi ; adeo ut perpetuam illic sedem 

 habere credibile sit hoc quidquid est portenti : cui certe simile aliud 

 nusquam apud reliquas fixas potui animadvertere. Nam creterse nebu- 

 losae olim existimata?, atque ipsa via lactea, perspicillo inspects, nullas 

 nebulas habere comperiuntur, neque aliud esse quam plurium stellarum 

 congeries et frequentia." — Christiani Hugenii, Opera varia, Lugd. Bat., 

 1724, p. 540-541. " Of these, however, those three almost contiguous 

 stars, and, with these, four others, shone, as it were, through a nebula, 

 so that the space around them, as is shown in this figure, is much more 

 brilliant than all the rest of the sky ; and when this is very serene and 

 appears quite dark, it seemed broken by a sort of gap, through which 

 one looked upon a brighter region behind. The same thing I have 

 since beheld over and over again, without any change in its appearance 

 and in the same position, so that one might almost believe that this 

 marvelous object, whatever it is, is permanently fixed there ; it is cer- 

 tain I have nowhere else noticed any thing similar to this in the other 

 fixed stars ; for those which have generally been considered as nebula?, 

 and even the Milky Way itself, when seen through a telescope, are found 

 to have nothing nebulous about them, but are nothing mote than a mul- 

 titude of several stars clustered together." Huygens himself estimated 

 the powers he employed in his twenty-five feet refractor as equal to a 

 hundred diameters (p. 538). Are the "quatuor stelhe trans nebulam 

 lucentes" the stars of the trapezium ? The small and very rough sketch 

 (Tab. xlvii., fig. 4, Phenomenon in Orione. Novum) represents only a group 



