(3^ Prof. Encke's Ephemeris for 1831. 177 



given divisor -|- throughout one half of it. The sign remains 



unchanged. These cohimns being of less importance, and as, 

 although incorrect, they truly indicate the position of the sa- 

 tellite with respect to the great axis, I have not deemed it ne- 

 cessary to give here the corrected values. 



The calculations of the path of the moon have again been 

 divided between Messrs. Herter, Wolfers, and Dannemann. 

 Science has lost the services of the latter gentleman by a 

 sudden and premature death, shortly after he had finished his 

 share of these calculations, when on the point of undertaking 

 a situation at the public school at Lingen. 



Mr. Herter has, besides, had the kindness to undertake the 

 calculations for Mercury ; while Mr. Wolfers has completely 

 calculated the paths of Venus, of Jupiter, and of Saturn, and 

 the occultations of Jupiter's satellites. 



The apparent places of Maskeiyne's thirty-six principal stars 

 will have, in this year's Ephemeris, an unequalled deo-ree of 

 accuracy, as Prof Bessel, at my request, has had the kindness to 

 have them calculated by one of his pupils, agreeably to his latest 

 investigations. The comparison of the calculations of 1830, 

 which has been added, proved that, with the exception of « 

 Aquila2, no alterations would have been required in the rio-lu 

 ascensions. For this star the correction is for Jan. 0... — 0"-012. 



The differences in the declinations do not exceed + 0"-02, 

 with the exception of « Orionis, whose declinations are to be 

 thus corrected. 



52-76 gi 4-9-61 26 57-12 jq., 60-59 73 



51-95 „Q 49-87 37 58-16 ^^ 5&'86 g, 



51-25;^ 50-24 ^^ 59-13 - 59-01 



50-66 50-74 _^ 60-00 58-06 



50-18 ^ 51-36 ^'" 60-71 ' 57-09^" 



49-83^^ 52-09 ''^ 61-24 '' 56-12^^ 



49-58-^ 52 93 ^^ 61-55 ^^ 55-20^- 



49-44 ^^j"* 53-87.^^ 61-65 !^ 54-37^^ 



49-40 - 54-99 



49-44 56-05 



17 



These differences, which never exceed 0"-2, were caused by an 

 error in tiie reduction to 1830. 



There is besides a difference of 0"-12 for the declination of 

 y Aquilui for Jan. 0, by which quantity the value given is too 

 small. 



The other nine stars will, indeed, not have the same accu- 

 racy, either as to the original mean position, or as to the 



iST. S. Vol. 7. No. 39. March 1830. 2 A manner 



