ASTRONOMY. 



By Professor Edward S. Holden, 



Director of the Washburn Observatory. 



The following record of the progress of Astronomy during the year 

 1884 is in continuation of the records for past years, and it is given in 

 essentially the same form. Abstracts of some of the most important 

 papers of the year are arranged under their appropriate heads. Other 

 papers, equally important, have been omitted, since they do not lend 

 themselves to condensation. 



To the professional astronomer these abstracts may serve as a con- 

 venient collection of notes. They are, however, primarily intended for 

 the large and increasing class of those who are interested in astronomy, 

 but whose acquaintance with the subject is more general than special. 

 The writer has made free use of reviews, etc., which have appeared in 

 the various scientific journals, more especially in Nature^ The Observa- 

 tory^ Bulletin Astronomique, iSirius, The Sidereal Messenger, The Athe- 

 naeum. 



CONSTRUCTION OF THE HEAVENS ; NEBULAR HYPOTHESIS, ETC. 



On the distribution of the stars in the northern hemisphere, by Prof. H. 



Seelig-er. 



[abstract. ] 



As is well known, the Durchmusterung of Argelander contains the po- 

 sitions and magnitudes of all stars visible in a 3-inch comet-seeker, with 

 a power of 10, from the north pole to — 2° declination. Professor Schoen- 

 feld has completed a similar Durchmusterung from —2° to — 23° which 

 is not yet published. The stars of these lists are between the 1.0 and 9.5 

 magnitudes (the last approximate only). In 1869 von Littrow had the 

 stars of the northern D. M. counted by magnitudes and by declination. 

 That is, he had the zones of 1° wide in declination counted, so as to ex- 

 hibit the number of stars of each tenth of a magnitude. Unfortunately 

 he did not separate the stars so as to exhibit the numbers in right as- 

 cension also, as he might easily have done. Professor Seeliger, of 

 Munich, has just completed a count of this kind. He was led to do this, 

 he says, because there was no such count in existence, and one was 

 peeked, It is clear that a kind of astronomical " clearing-house," where 



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