Royal Astronomical Society. 61 



rent right ascensions and north polar distances are given, together 

 with the differences arising from a comparison of their places, as 

 given in the Berlin Ephemeris. The observed right ascension of 

 Uranus is less than its computed right ascension, by a quantity 

 varying from 1-,12 to2S09, and its polar distance is less, by a quan- 

 tity varying from ^",Sl to 12",91. The difference in the right 

 ascension of Jupiter varies from — 0%06 to +0",70, and in polar 

 distance from +0",36 to —&',^5. The difference in the right as- 

 cension of Vesta varies from — 0%56 to +0%36, and in polar di- 

 stance from — 2",25 to — 17",20. The difference in the right ascen- 

 sion of Mars varies from —0^43 to -|-1',02, and in polar distance 

 from -14",25 to +7",64. 



V. Extract of a letter from M. Cauchoix to Mr. Lubbock, dated 

 October 1831. 



" I have just finished another object-glass, of the same dimen- 

 sions as that which Sir James South is now mounting, and which 

 appears to nie as perfect. I used for it one of the three pieces of 

 glass which were set apart for the first object-glass, and I have 

 adapted to it a new disc of flint-glass. A trial of it with Jupiter 

 does not detect any flaw, either in the flint- or crown-glass. 1 hope 

 also to be able to make a third glass of similar dimensions, as well 

 as another glass of the same size as that which Mr. Cooper has 

 lately bought of me. I have likewise another kind of telescope, 

 which 1 have made for these two or three years, where rock-crystitl 

 is substituted for the crown-glass, by which means the focus is con- 

 siderably shortened, and the brilliancy and clearness of the image 

 gieatly Increased. But, at present, 1 have not been able to make 

 them of larger diameter than about 5\ English inches." 



VI. A Catalogue of stars, observed with the moon, from June 

 to October, 1831, at the Greenwich Observatory. From the Astro- 

 nonier Royal : — 



J 83 1. h m s 



June 20 ]) 1 L 14 36 51-54. 



2 g Librae 14 48 5-08 



21 ]) 1 L 15 24 52-90 



^ Librffi 15 35 3-78 



9 Libra 15 44 42 04 



24 J IL 17 56 25-48 



(21)Sagittar 18 15 48-16 



(94)Sagittar 18 22 26-90 



July 22 D IL 18 30 45-98 



0' Sagittar 18 48 1-20 



(316) Sagittar 19 33-44 



^Sagittar 19 8 28-24 



\UK 19 (112)Sagittar 18 26 22-26 



r Sagittar 18 40 35-06 



?' Sagittar 18 4S 14-53 



J IL 19 3 18-36 



Sept 22 . . . . ( 120 ) Piscium .... 27 20-40 



* 5 2L 59 10 66 



* Oct. 16. 



