'2%i Mr. Herschel on the 



direction, refembling the (hoals that are feen near the coafts of 



fome iflands. 



The nhith is that hi the girdle of Andromeda, which is un- 

 doubtedly the nearefl: of all the great nebulse ; its extent is 

 above a degree and a half in length, and, in even one of the 

 narrowed places, not lefs than i6^ in breadth. The brighteft 

 part of it approaches to the refolvable nebuloiity, and beghis 

 to fliew a faint red colour ; which, from many obfervations on 

 the colour and magnitude of nebuliE, J believe to be an indica- 

 tion that its diflance in this Coloured part does not exceed 2000 

 times the diflance of Sirius. There is a very confiderable, 

 broad, pretty faint, fmali nebula near it ; my Sifter difcovered 

 it Augufl: 27, 178 ;, with a Newtonian 2-feet fweeper. It flicws 

 the fame faint colour with the great one, and is, no doubt, in 

 the neighbourhood of it. It is not the 3 2d of the Connoiffance' 

 des Temps ; which is a pretty large round' nebula, much con- 

 denfed in the middle, and fouth following the great one ; but 

 this is about two-thirds of a degree north preceding it, in a 

 line parallel to /3 and v Andromedie. 



To thefe may be added the nebula in Vulpecula : for, though 

 its appearance is not large, it is probably a double flratum of 

 ftars of a very great extent, one end whereof is turned towards 

 us. That it is thus fituated may be furmifed from its contain- 

 ing, in diiferent parts, nearly all the three nebulofities ; viz. 

 the refolvable, the coloured but irrefolvable, and a tin6lure of 

 the milky kind. Now, what great length muft be required to 

 produce thefe effects may eafily be conceived when, in all pro- 

 bability, our whole fyftem, of about 8co ftars in diameter, if 

 it were feen at fuch a diftance that one end of it might aliume- 

 the refolvable nebulofity, would not, at the other end, prefent 



\3S 



