ASTRONOMY. 9 



elements satisfy the normal places well: = 8.639", and 

 Struve has found the parallax 0.154"; mass of the system, 

 4.63, that of the sun being 1, and a=56.10, the earth's mean 

 distance being 1. 



STAR CATALOGUES AND MAPS. 



The progress made in the zones of the AstronomiscJie 

 Gesellschaft cannot be definitely stated until after the pub- 

 lication of the report of their meeting at Stockholm. The 

 "Durchmusteruns: ties Nordlichen Gestirnten Himmels," the 

 joint work of Argelander and his assistants, Kriiger and 

 Schonfeld, embraces all the stars of the first nine magnitudes 

 from the North Pole to 2 of south declination. This work 

 was begun in 1852, and at its completion a catalogue of the 

 approximate places of no less than 324,198 stars, with a series 

 of excellent star-maps giving the aspect of the northern heav- 

 ens for 1855, was at the service of astronomers, and has been 

 in the most constant use from that time forward. Argelan- 

 der's original plan was to carry this Durchmusterung as far as 

 23 south, so that every star visible in a small comet-seeker 

 should be registered. His original plan was abandoned, but 

 his former assistant and present successor at the Observatory 

 of Bonn, Dr. Schonfeld, is now engaged in executing this 

 important work. The same methods will be followed by 

 Schonfeld which were so successful formerly; the equinox 

 of 1855 is chosen as the fundamental one; and almost the 

 only changes are the adoption of a telescope of six inches 

 aperture for the work, and a closer discrimination of the 

 magnitudes of the fainter order of stars. In the prosecution 

 of the plan, Schonfeld has already determined the position of 

 74,885 stars; and astronomers in the northern hemisphere 

 will soon possess an index, as it were, to every star likely 

 to be used in their observations. 



The last report of the National Observatory of the 

 Argentine Republic is dated March, 1876. Dr. Gould re- 

 ports that the Uranometry is ready for the press, except 

 the text. The Zones, which were begun September 9, 1872, 

 were finished August 9, 1875, and contain over 105,000 

 stars, and comprise the region from 22 50' to 88 10'. 

 The Standard Catalogue now contains 4253 stars (12,661 

 observations), besides 54 circumpolars (1461 observations), 



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