Conjiru5lhn of the Heavtns, a^-* 



us with the Irrefolvable, much lefs with the colourlefs and 

 milky fort of nebuloiities. 



A F erf orated 'Nebula^ or Ring of Stars, 

 Among the curiofities of the heavens fhoLild be placed a 

 nebula, that has a regular, concentric, dark fpot in the middle, 

 and is probably a Ring of ftars. It is of an oval Jfhape, the 

 fliorter axis being to the longer as about 83 to 100 ; fo that, if 

 the flars form a circle, its inclination to a line drawn from the 

 fun to the center of this nebula mufl be about ^6 degrees. The 

 light is of the refolvable kind, and in the northern fide three 

 very fbiint (lars may be feen, as alfo one or two in the foutherii 

 part. The vertices of the longer axis feem lefs bright and not 

 fo well defined as the reft. There are feveral fmall flars very 

 near, but none that feem to belong to it. It is the c-^th of 

 the ConnoiJJance des Temps, Fig. 5. is a reprefentation of it. 



Planetary Ntbul^e. 



I ihall conclude this paper with an account of a few hea- 

 venly bodies, that from their lingular appearance leave me almofl 

 ill doubt where to clafs them. 



The firft precedes v Aquarli 5^,4 in time, and is i^ more 

 north, its place, with regard to a fmall ftar Sept. 7, 1782, 

 was, Diflance 8' j ^" 5 1^^^ ; but on account of the low fituation, 

 and other unfavourable circumftances, the meafure cannot be 

 very exa£l. Auguft 25, T783, Diflance 7^ 5^^ 11^^', veryexa<5t, 

 and to my fatisfa^lion ; the light being thrown in by an opaque- 

 microfcopic-iUumination (£•). Sept. 20, 1783, Pofition 41° 24.' 



fouth 



{g) It mny be of ufe to explain thrs kind of illumination for which the New- 

 tonian refleftoF is admirably confifufted. On the fide oppofite the eye-piece an 

 opening is to be made in the tube, through which the^light may be thrown in, {o 

 as to tall oa fome refleding body, or concave perforated mirror^, witliin the eye- 



piece^ 



