OF ARTS AND SCIENCES. 



295 



January 1, 1848, 

 April 1, 

 July 1, 



October 1, " 

 January 1, 1849, 

 April 1, 

 July 1, 



October 1, " 

 January 1, 1850, 

 April 1, 

 July 1, 



October 1, " 

 January 1,^1851, 



+ 22.58 

 4- 20.40 

 -f 17.89 

 + 15.12 

 -|- 12.18 



+ 

 + 

 + 



9.06 

 5.84 

 2.59 

 0.64 

 3.83 

 6.96 

 9.96 

 12.64 



+ 0.01491 

 + 0.01443 

 ■f 0.01400 

 + 0.01363 

 4- 0.01332 

 4- 0.01308 

 -f 0.01290 

 -|- 0.01277 

 4- 0.01270 

 4- 0.01270 

 + 0.01276 

 + 0.01288 

 4- 0.01308." 



Professor Peirce also communicated the following elements 

 of the orbit of the satellite of Neptune, computed from the 

 combination of all of Lassell's and Mr. Bond's observations; 

 and he also communicated the corresponding mass of the 

 primary. , 



" Time of sidereal revolution, 5 days 21 hours 12,4 minutes. 



" Inclination to ecliptic, 29°. 9. 



" Longitude of ascending node (the motion being supposed di- 

 rect), 119='.8. 



" Time of greatest northern elongation, November 26''-.53, Green- 

 wich mean solar time. 



" Greatest elongation, 16". 5. 



" Distance of satellite from Neptune, 230,000 miles. 



" Corresponding mass of Neptune, tbtsttj t^® mass of sun being 

 unity. 



" The time of sidereal revolution is not liable to an error of more 

 than a few minutes, and the greatest elongation cannot be less than 

 16".3, or more than 17".0. The mass of Neptune, therefore, cannot 

 be less than y^i^^, or greater t];ian xr^ffty" 



