On the Comet of July — Septemler 1819. 



47 



up to August 1, IS 19. And as in the course of observation I 

 was obliged to resort to Lalande's Histoire Celeste, 1 have in- 

 serted in the plate twelve additional stars from that work, (all of 

 them near the comet's path,) and have distinguished them by 

 Roman letters ; viz. 



C 



D 



E 



F 



G 



H 



B 



I 



K 



L 



M 



N 



a i: 



Histoire Cel. Fr. 



5 



7-8 



7 



7 



7 

 7-8 



8 

 7-8 



9 



9 

 8-9 

 8-9 



8 



Pa^e. 



Transit. 



383 



377 

 564 



383 



Approx. Posit. Aug. 1, 1819. 



Rt. Ascen. 



} 



106 



108 



108 

 111 

 113 

 118 

 124 

 129 

 129 

 129 

 132 

 132 



11-8 



5-1 



50 

 24-2 



6-8 

 52-6 

 40 



0-2 

 29-7 

 58-2 

 14-0 

 350 



Declination- 



49 46-4 

 48 52-3 



48 16-7 



50 55-8 



51 27-0 

 49-S 

 14 



5-7 

 0-4 

 50 36-9 

 50 26-5 

 50 39-1 



51 

 51 

 50 

 50 



Flamstead has three imperfect observations of the first star C, 

 which is No. 396 of Miss Herschel's catalogue; and 1 have rea- 

 son to believe it is the same with Hevelii S Lynciff ; as the longi- 

 tude and latitude of the latter, given iti the Tables de Berlin, 

 correspond to it, while in Wollaston's catalogue the declination 

 is six degrees greater, and perhaps may have arisen from a typo- 

 graphical error in the original. 



The account given of the comet when first seen at Paris, is, 

 that the nucleus appeared very luminous, pretty well defined, and 

 of a shape inclining to oval. The tail might be about six or 

 seven degrees in length. 



The smaller compartment of the plate exhibits a projection of 

 its orbit on the plane of the ecliptic, according to the subjoined 

 elements, corrected by Bouvard, which represent the observed 

 places of the comet to within 50". Perihelion passage June 28, 

 2225, mean time at Paris*, i. e. June 27, at 17*" ll"" at Green- 

 wich ; perihelion distance 0-34 lOOS; longitude 287° 5' 54" ; 

 longitude of ascending node 273" 42' 52"j inclination of orbit 

 80' 44' 44" ; motion direct. 



* TJiC French astronomical time is reckoned from midnight, the English 

 from noon; there is consctiucntly a dift'erentc between them of 12'' 'J'" 21: 



The 



