Life, Researches , and Discoveries of F. W. Bessel 307 



his search among Harriott's papers, in the possession of the Earl 

 of Egremont ; and, being the first observations of this remark- 

 able body made with any kind of instrumental aid, their reduc- 

 tion was an object of undeniable importance. This task Bessel 

 executed in so masterly a manner, as to call forth the warmest 

 eulogies from Olbers to whom he communicated them, and to 

 excite the strongest desire in him to secure for astronomy one 

 whose future eminence in that science he clearly foresaw, and in 

 no sparing or measured terms predicted. This performance, his 

 first public work, appeared in Zach's Monathliche Correspon- 

 denz, and was immediately followed by a theoretical memoir, 

 of great importance, " On the calculation of the true anomaly in 

 orbits nearly parabolic. 7 ' So expert had he become in cometic 

 calculations, that Olbers, having placed in his hands, on the night 

 of the 1st of November, 1805, four observations of the comet of 

 that year, he returned them to him the next morning, with the 

 elements, whose calculation had occupied him only four hours. 



His seven years' engagement with Messrs. Kuhlenkamp was 

 now terminated ; but, instead of entering on the mercantile world 

 on his own account, we find him placed forthwith, at the recom- 

 mendation of Olbers, as assistant to Schroter, at Lilienthal, and 

 successor to Harding. Astronomy thus became his profession : 

 he gave himself wholly to it, with an energy and success which 

 very speedily placed him in the first rank of its cultivators. 



The instruments of Schroter were better adapted for physical 

 examination than for precise astronomical determinations. Among 

 the more especial objects to which his attention, 'as an observer, 

 was there directed, may be mentioned a series of micrometrical 

 measures of the distances of the sixth, or Huygenian, satellite of 

 Saturn from the ring, made with a Newtonian reflector by the 

 aj d of the projection micrometer, with a view to the better deter- 

 mination of the mass of Saturn and of its ring, by means of the 

 perturbations caused thereby in the satellite's motions. This 

 w °rk, so begun, was never subsequently lost sight of. It forms 

 *e subject of several elaborate memoirs, the first of which ap- 

 P^red in the Konigsberger Archiv fur Nahmvissenschaften, No. 

 2 > in which all the^observed conjunctions and oppositions of the 

 ^ellite, and all the recorded disappearances of the ring, are sub- 

 bed to a rigorous and systematic calculation; the position of 

 the ring kself normally determined, together with elements of 

 the orbit of the satellite in question, and even the perturbations 

 ot "s motion by the attraction of the ring and by the sun are 

 m *de objects of minute inquiry. The subject was resumed as 

 £ bs ervations accumulated, especially those made with the cele- 

 J ra ted heiiometer of Fraunhofer, in three admirable papers, Nos. 

 * 93 -5, X . 214, and No. 242 of the Astronomische Nachrichten^ 

 At Li ipntVini -*i« «***«» v^orio hie n^Qprvntions of the comet of 



