ICO SCIENTIFIC RECORD FOR 1884. 



accounts can be adjusted, is also needed ! A count of this kind, exists 

 in MS. at the Bonn Observatory (see Bonn Obs., vol. v), but is not ac- 

 cessible. The Washburn Observatory prints in its vol. iii, the begin- 

 ning of a count of this kind (from — 2° to -f 13°), which was stopped 

 on hearing of Professor Seeliger's. Professor Seeliger appears also to 

 be unaware that Littrow's count has been repeated by Mr. Peirce {An- 

 nals H. G. 0., vol. IX) ! With this digression, which is not uninstructive, 

 we return to Professor Seeliger's important paper. He has then counted 

 the stars of the D. M. accurately, and by R. A. as well as Decl. and Mag. 

 Instead of keeping magnitudes down to the tenths, he has wisely se- 

 lected the following classes : 



1. Containing stars from 1.0 to 6.5 mags., inclusive. 



2. Containing stars from 6.6 to 7.0 mags., inclusive. 



3. Containing stars from 7.1 to 7.5 mags., inclusive. 



4. Containing stars from 7.6 to 8.0 mags., inclusive. 



5. Containing stars from 8.1 to 8.5 mags., inclusive. 



6. Containing stars from 8.6 'to 9.0 mags., inclusive. 



7. Containing stars from 9.1 to 9.5 mags., inclusive. 



The number of stars for each 20"* of R. A. and each l'^ of Dec. was 

 counted. These numbers have been united into sums giving new num- 

 bers of stars in areas of 20'" in R. A. by 5° in Dec. The latter tables 

 are to be printed by the Munich Observatory. 



Professor Seeliger's paper contains the number of stars for each area 

 of 40™ in R. A. by 5° in Dec, the stars of each class 1-7 being enu- 

 merated separately. There are, in the northern sky, 4,120 objects of 

 class 1 ; 3,887 class 2 ; 6,054 class 3 ; 11,168 class 4 ; 22,898 class 5 ; 

 52,852 class 6 ; 213,973 class 7 ; 314,952 in all, besides 126 nebulte, va- 

 riables, etc. That is 315,078 in all, by Professor Seeliger's count. Ar- 

 gelander gives 315,089. To deal with this mass of figures, Professor 

 Seeliger divides the sky^into 8 zones. Zone 1 has its center at the north 

 pole of the Milky Way, and extends to Galactic Polar Distance 20° ; 

 zone 2 extends from G. P. D. 20° to 40°: zone 3, from 40° to 60° ; zone 

 4, from 60° to 80° ; zone 5 (containing the Milky Way itself) from 80° to 

 100°, and so on to G. P. D. 140°. 



The number of stars (of each class) per zone is next determined ; and 

 next the number of stars (of each class) in each 1° square. We may 

 quote the figures for class 1 and classes 2-7 taken together : 



Class 1. Classes 2-7. 



Zone 1 0.15 8.51 



2 0.15 8.95 



3 0.17 11.02 



4 0.21 16.77 



5 0.27 24.60 



6 0.25 18.92 



7 0.15 11.59 



8 0.12 10.19 



