100 



EECORD OF SCIENCE FOR 1886. 



The stars are divided into eight classes, one more than ])reviously 

 nsed, as Schonfekl has included stars of the tenth magnitude, whereas 

 Argelander stopped at 9.5. 



Schoufeld's zones begin at — 2°, but the " counts " maj' be carried up 

 to the equator by utilizing Argelander's work ; the slight difference in 

 limiting magnitude will not affect materially the result. The stars 

 embraced in each degree of declination have been divided into groui)s 

 of twenty minutes in right ascension, though only the sums for each 

 forty minutes have been published. 



The number of stars in each of the eight classes is as follows: 



The numbers in column A comprise Schonfeld's stars only ; column 

 B includes Argelander's stars, from 0=^ to — 12<^, for the first seven 

 classes: to complete Class VIII about 3, GOO should be added. The 

 number of stars thus counted in the "Southern Durchmusterung" proper 

 is, therefore, 133,580, and adding to this 79 objects which are classed as 

 nebuhe or variables, there results the grand total, 133,659. 



In order to investigate the influence of the Milky AYay on the distri- 

 bution of these stars. Professor Seeliger proceeds, as in his ^former 

 paper, to form the " gradient," which expresses for each class the 

 rapidity of increase in the number of stars as we approach the Milky 

 Way. Comparing the values of the gradient with these found for 

 Argelander's Durchmusterung, it is seen that, as far as Schonfeld's 

 work can be considered typical of the southern hemisphere as a whole 

 (it must be remembered, however, that it only embraces one-third 

 thereof) the influence of the Milky Way on stellar distribution, at least 

 for stars down to the eighth magnitude, api)ears to be less marked for 

 the southern than for the northern hemisphere. But it may well be 

 that, especially in the higher classesof stars, local and accidental irreg- 

 ularities are the cause of this apparent difference. With regard to the 

 question as to which hemisphere is the richer in stars, it ap{)ears that 

 there is no decided difference shown by the two surveys under consider- 

 ation. When Argelander's numbers are corrected so as to be com[)ara- 

 ble with Shoufeld's, taking stars down to the ninth magnitude, iuclu- 



