An Account of a new Catalogue of Stars. 339 



Cor. 5. — Let the three diagonals of the inscribed hexagon 

 meet the three diagonals joining the opposite summits of the 

 tangential triangles in t, u, v ; these three points are in one 

 straight line. 



Several theorems analogous to these have been omitted on 

 account of the extreme complication of their respective dia- 

 grams. 



Bath, Sept. 1826. 



LI. An Account of a new Catalogue of Stars, recently 'published 

 by the Astronomical Society of London. 



T^HIS catalogue contains the mean places (reduced to Ja- 

 A nuary 1, 1830) of nearly three thousand principal stars : 

 together with the logarithms of certain constants for deter- 

 mining their precession, aberration and nutation ; and by the 

 help of which, those quantities may be computed with much 

 greater ease and expedition than by any other method hitherto 

 made known. An introduction is prefixed to the tables, by 

 Mr. Baily, President of the Society, explanatory of their con- 

 struction and use : and from which we select the following 

 passages : 



" Special tables, for computing the aberration and nutation 

 of particular stars, have for a long time been used by astro- 

 nomers. The first distinct publication of this kind was by 

 M. Mezger; who published at Manheim in 1778, his Tabulce 

 Aberrationis et Nutationis for 352 stars. There had, how- 

 ever, previously to that period, appeared in the volumes of 

 the Connaissance des terns from 1760 to 1774, several tables of 

 a similar kind, and containing many of the same stars : which 

 tables, M. Jeaurat subsequently collected together, and pub- 

 lished in the Con. des terns for 1781. They were afterwards 

 revised by M. Delambre, and published (252 in number) in 

 the Con. des terns for 1789 — 1791. An addition of 116 stars 

 was made in the Con. des terns for 1802; and a further addi- 

 tion of 142 stars, in the same work for 1806 : thus making the 

 total number 510. In the Ephemerides de Vienne for the years 

 1784 and 1785, M. Pilgram published special tables for 500 

 stars : but they are said to contain so many errors that it is 

 unsafe to- use them. In the year 1807, two other sets of spe- 

 cial tables appeared, comprising nearly the same stars as those 

 already alluded to: one by M. Cagnoli, containing 501 stars: 

 the other by Baron Zach, containing 494 stars. The former 

 is entitled Catalogue de 501 etoiles, suivi des tables relatives 



2 U 2 d' Aberration 



