STAR CATALOGUES. 115 



La Caille, Tobias Mayer, Cagnoli, Piazzi, Zach, Pond, Taylor, 

 Groombridge, Argelander, Airy, Brisbane, and Riimker. 



We here only allude to those works which enumerate a 

 great and important part* of the stars of the se\ enth to the 

 tenth magnitude which occupy the realms of space. Tho 

 catalogue known under the name of Jerome de Lalandc's, 

 but which is, however, solely based on observations made by 

 his nephew, Francois de Lalande, and by Burckhardt between 

 the years 1789 and 1800, has only recently been duly appre- 

 ciated. After having been carefully revised by Francis Baily, 

 under the direction of the " British Association for the Ad- 

 vancement of Science" (in 1847), it now contains 47,390 

 stars, many of which are of the ninth, and some even below 

 that magnitude. Harding, the discoverer of Juno, catalogued 

 above 50,000 stars in twenty-seven maps. Bessel's great 

 work on the exploration of the celestial zones, which comprises 

 75,000 observations (made in the years 1825-1833 between 

 15 and +45 declination), has been continued from 1841 

 to 1844 with the most praiseworthy care, as far as +80 

 deck, by Argelander at Bonn. Weisse of Cracow, under the 

 auspices of the Academy of St. Petersburgh, has reduced 

 31,895 stars for the year 1825 (of which 19,738 belonged to 

 the ninth magnitude) from Bessel's zones, between 15 and 

 + 15 deck ;t and Argelander' s exploration of the northern 

 heavens from +45 to +80 deck contains about 22,000 

 well-determined positions of stars. 



* I here compress into a note the numerical data taken from star cat- 

 alogues, containing lesser masses and a smaller number of positions, 

 with the names of the observers, and the number of positions attached : 

 La Caille, in scarcely ten months, during the years 1751 and 1752, with 

 instruments magnifying only eight times, observed 9766 southern stars, 

 to the seventh magnitude inclusive, which were reduced to the year 

 1750 by Henderson ; Tobias Mayer, 998 stars to 1756 ; Flamstead, orig- 

 inally only 2866, to which 564 were added by Baily's care {Mem. of the 

 Astr. Soc, vol. iv., p. 1291-64); Bradley, 3222, reduced by Bessel to 

 the year 1755; Pond, 1112; Piazzi, 7646 to 1800; Groombridge, 4243, 

 mostly circumpolar stars, to 1810; Sir Thomas Brisbane, and Rtimker, 

 7385 stars, observed in New Holland in the years 1822-1828 ; Airy, 2156 

 stars, reduced to the year 1845 ; Riimker, 12,000 on the Hamburg hori- 

 zon; Argelander (Cat. of Abo), 560; Taylor (Madras), 11,015. The 

 British Association Catalogue of Stars (1845), drawn up under Baily's 

 superintendence., contains 8377 stars from the first to 7 magnitudes. 

 For the southern stars we have the rich catalogues of Henderson, Fal- 

 lows, Maclear, and Johnson at St. Helena. 



t Weisse, Positiones media stellarum fixarum in Zonis Regiomontanit 

 a Besselio inter 15 el -j-15 decl. observatarum ad annum 1825 re 

 duetts (1846); with an important Preface by Struve. 



