22 VHILOSOPHICAL TRANSACTIONS. [aNNO 17QI- 



to an assemblage of stars is, that we could not easily assign any other cause ot" 

 sufficient importance for such luminous appearances, to reach us at the immense 

 distance we must suppose ourselves to be from them. But if an argument of 

 considerable force should now be brought forward, to show the existence of a 

 luminous matter, in a state of modification very different from the construction 

 of a sun or star, all objections, drawn from our incapacity of accounting for new 

 phenomena on old principles, he thinks, will lose their validity. 



Hitherto Dr. H. has been showing, by various instances in objects whose places 

 are given, in what manner we may form the ideas of connection, and its con- 

 trary, by an attentive inspection of them only ; lie now relates a series of obser- 

 vations, with remarks on them as they are delivered, from which he afterwards 

 draws a few simple conclusions, that seem to be of considerable importance. 



Oct. 16, 1784. A star of about the 9th magnitude, surrounded by a milky 

 nebulosity, or chevelure, of about 3' in diameter. The nebulosity is very faint, 

 and a little extended or elliptical, the extent being not far from the meridian, or 

 a little from north preceding to south following. The chevelure involves a small 

 star, which is about 1^ north of the cloudy star; other stars of equal magnitude 

 are perfectly free from this appearance, (r. a. 5'' 5/™ 4'. p. d. 96° 22'). His 

 present judgment concerning this remarkable object is, that the nebulosity be- 

 longs to the star which is situated in its centre. The small one, on the contrary, 

 which is mentioned as involved, being one of many that are profusely scat- 

 tered over this rich neighbourhood, he supposes to be quite unconnected with 

 this phenomenon. A circle of 3' in diameter is sufficiently large to admit an- 

 other small star, without any bias to the judgment he formed concerning the one 

 in question. It must appear singular, that such an object should not have imme- 

 diately suggested all the remarks contained in this paper; but about things that 

 appear new we ought not to form opinions too hastily, and his observations on 

 the construction of the heavens were then but entered on. In this case there- 

 fore, it was the safest way to lay down a rule not to reason on the phenomena 

 that might ofFer themselves, till he should be in possession of a sufficient stock of 

 materials to guide his researches. 



Oct. 16, 1784. A small star of about the Uth or 12th magnitude, very 

 faintly affected with milky nebulosity ; other stars of the same magnitude were 

 perfectly free from this appearance. Another observation mentions 5 or small 

 stars within the space of 3 or 4', all very faintly affected in the same maimer, 

 and the nebulosity suspected to be a little stronger about each star. But a third 

 observation rather opposes this increase of the faintly luminous appearance. 

 (r. a. 6'' 0"> 33», p. D. 96" 13). Here the connection between the stars and the 

 nebulosity is not so evident as to amount to conviction ; for which reason we 

 shall pass on to the next. 



