DE vice's COMET OF 1844. 137 



was ascertained that the curve described was an ellipse 

 with a periodic time of about five and a half years. Dr. 

 Briinnow (formerly of Berlin, but now director of the 

 observatory at Ann Arbor, Mich.), undertook a thorough 

 investigation of all the observations, embracing a period 

 of more than four months, and took account of all 

 the planets within the orbit of Uranus. He thus ob- 

 tained an orbit which satisfied all the observations with 

 extreme precision, and indicated that the length of the 

 comet's revolution was 1996.5 days, or 5.4659 years. 

 This period (supposing its orbit undisturbed) would bring 

 the comet back to perihelion about the 20th of Feb- 

 ruary, 1850 ; but it happened, very unfortunately, that 

 when the comet was near enough to the earth to be 

 otherwise discerned, it was always lost in the sun's rays ; 

 the geocentric positions of the sun and comet at perihe- 

 lion being nearly the same, and continuing so for some 

 months, on account of the apparent direct movement of 

 both bodies. 



At the next visit, in the summer of 1855, it was sup- 

 posed that the comet would be more favorably located in 

 the heavens, and astronomers looked forward with great 

 interest for its reappearance. Dr. Briinnow calculated 

 that it would be in perihelion on the evening of August 

 6th, 1855. Only one observation of this body has been 

 reported from any part of the world. On the 16th of May, 

 M. Hermann Goldschmidt, of Paris, while searching for 

 the comet, found a nebulous body whose right ascension 

 was 21h. 41m. 45s. ; declination 15 38'south. It was faint, 



