106 RECORD OF SCIENCE FOR 1886. 



Right ascensions are given to seconds of time, declinations to the nearest 

 tenth of a minute of arc The catalogue proper is followed by several 

 useful pages of notes. 



Edinburgh catalogue. — Prof. Piazzi Smyth has given in \'olume xv of 

 the Edinburgh Astronomical Observations the results of observations 

 made from 1833 to 1872 upon some 3.890 B. A. C. stars, reduced to the 

 epochs 1830, 1870, 1880, and 1890. The catalogue begins with 1'' 0'" of 

 right ascension, the first four hours having ai)poared nine years ago as 

 volume XIV. The notes contain information in regard to the proper 

 motion, color, or duplicity of the stars. 



Second Armagh catalogue o/ 3,300 stars for 1875.0. — After tlie comple- 

 tion of the observations of Bradh\v's stars, the results of which were em- 

 bodied in the catalogue commonly known as the " Armagh Catalogue," 

 Dr. Eobinson formed the i)lan of re-observing a number of stars from 

 Lalande's " Histoire celeste," occurring in Baily's catalogue. Observa- 

 tions were couimeuced in 1859 with the 3i|-inch nniral circle and transit, 

 but were stopped after 1800 in order to change the mural into a 7-inch 

 transit circle. Work was resumed in 1803, and continued with more or 

 less regularity till 1883. The right ascensions of this catalogue depend 

 on the standard stars of the " jSTautical Almanac; " the north polar dis- 

 tances upon observations of the nadir. Dr. Dreyer, who succeeded Dr. 

 Robinson in 1882, found from 400 observations of 80 stars between 30° 

 and 100° N. P. D., that the probable error of a single observation in 

 right ascension was i 0^081, (the single errors having been multiplied 

 by cos 6); and in north polar distance i0".85. For systematic errors 

 Armagh has been compared with Glasgow, and, indirectly through the 

 latter, a comparison is obtained with Auwers' fundamental system. 

 From this comparison it appears that the north polar distances are in 

 fair agreement witli Auwers' catalogue, while the right ascensions 

 show considerable dis(;ordances. 



ReliahiUty of the star-places of Auioers'' Fundamental Catalogue. — Mr. 

 Chandler, having pointed out the possibility of error in the places of 

 certain stars (Observatory 8: 387), as given in the Berlin " Jahrbuch," 

 Herr Auwers has been induced to publish (Astron. Nachr., 114: 1-20) 

 some valuable and iuteresting remarks on the reliability of the ])laces 

 of his Fundamental Catalogue (Pub. d; astron. Gesellsch., 14), from which 

 those given iu the Berlin " Jaiirbuch" are derived. Herr Auwers ex- 

 ])lains the provisional character of the data ou which some of his star- 

 places depend, and repeats in a more definite manner what he has already 

 said ou the subject in Publication xiv. In fact the proper motions 

 adoi)ted for some of the stars are merely provisional, as has been pointed 

 out in the introduction to the catalogue. The pro])er motions employed 

 have been, as a rule, obtained from a comparison of Bradley's places 

 with those of Greenwich, 1801, and in those cases in which Bradley has 

 only one observation, or observed the star iu one element only, the 

 proper motion is given to one decimal place less than usual. The reader 



