24 PHILOSOPHICAL TRANSACTIONS. [aNNO 1791- 



Nov. 25, 1788. A star of about the Qth magnitude, surrounded with very 

 faint milky nebulosity; other stars of the same size are perfectly free from 

 that appearance. Less than 1' in diameter. The star is either not round or 

 double (a). 



March 23, 178g. A bright, considerably well defined nucleus, with a very 

 faint, small, round chevelure (/!). The connection admits of no doubt; but the 

 object is not perhaps of the same nature with those called cloudy stars. 



April 14, 1789. A considerable, bright, round nebula; having a large place 

 in the middle of nearly an equal brightness, but less bright towards the margin 

 (c). This seems rather to approach to the planetary sort. 



March 5, 179O. A pretty considerable star of the 9th or 10th magnitude, 

 visibly affected with very faint nebulosity of little extent, all around. A power 

 of 300 showed the nebulosity of greater extent (d). The connection is not to 

 be doubted. 



March 19, 1790. A very bright nucleus, with a small, very faint chevelure, 

 exactly round. In a low situation, where the chevelure could hardly be seen, 

 this object would put on the appearance of an ill-defined, planetary nebula, of 

 6, 8, or 10" diameter (e). 



Nov. 13, 1790. A most singular phenomenon! A star of about the 8th 

 magnitude, with a faint luminous atmosphere, of a circular form, and of about 

 3' in diameter. The star is perfectly in the centre, and the atmosphere is so 

 diluted, faint, and equal throughout, that there can be no surmise of its con- 

 sisting of stars; nor can there be a doubt of the evident connection between the 

 atmosphere and the star. Another star not much less in brightness, and in the 

 same field with the above,, was perfectly free from any such appearance {/). 

 This last object is so decisive in every particular. Dr. H. says, that we need 

 not hesitate to admit it as a pattern, from which we are authorised to draw the 

 following important consequences. 



Supposing the connection between the star and its surrounding nebulosity to 

 be allowed, we argue, that 1 of tiie 2 following cases must necessarily be ad- 

 mitted. In the first place, if the nebulosity consist of stars that are very remote, 

 which appear nebulous on account of the small angles their mutual distances 

 subtend at the eye, by which they will not only, as it were, run into each other, 

 but also appear extremely faint and diluted; then, what must be the enormous 

 size of the central point, which outshines all the rest in so superlative a degree 

 as to admit of no comparison .'' In the next place, if the star be no larger than 

 common, how very small and compressed must be those other luminous points 



(a) K. A. l" 57', P. D. 18° 41'. (b) n. A. 1 1" IS™ 25% P. D. 50° 17'. (c) u. a. IT-J-S^IS', 

 r. D. 33° 43'. (d) r. a. 6" 58'" 40', p. d. yi° 29'. (c) r. a. ^''S?" 2'2\ e. i). 30° 11'. (/) r. a. 

 3" 56" 48', P. D. 5y° 50'. 



