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galactic poles, as supposed by Herschel and Struve. In the language of 

 Seeliger: "The Milky Way is no merely local phenomenon, but is closely 

 connected with the entire constitution of our stellar system." 



This conclusion is strengthened by a study of the data given by 

 Celoria. It will be remarked that the zone counted by this astronomer 

 cuts the Milky Way diagonally at an angle of about 62°, and, therefore, 

 does not take in either of its poles. Consequently, regions I. and IX. 

 are both left out. For the remaining seven regions the results are 

 shown as follows: We show first the area, in square degrees, of each of 

 the regions, II. to VII., included in Celoria's zone. Then follows in the 

 next column the number of stars counted by Celoria, and, in the third, 

 the number enumerated in the Durchmusterung in these portions of each 

 region. The quotients show the star-density, or the mean number of 

 stars per square degree, recorded by each authority: 



Area. Number of Stars. Star-Density. 



Region. Degrees. Cel. D. M. Cel. D. M. 



II 404.4 27,352 1,230 67.6 3.04 



III 284.6 22,551 932 79.3 3.28 



IV 254.6 29,469 1,488 115.7 5.83 



V 284.6 41,820 1,833 146.9 6.44 



VI 284.6 31,706 1,472 111.4 5.22 



VII 329.5 25,618 1,342 77.7 4.07 



VIII 314.5 22,264 1,184 70.8 3.77 



It will be seen that the law of increasing star-density from near 

 the galactic pole to the galaxy itself is of the same general character 

 in the two cases. The number of stars counted by Celoria is generally 

 between 18 and 25 times the number in the Durchmusterung. 



An important point to be attended to hereafter is that the star- 

 density of the Milky Way itself, as derived from each authority, is 

 between two and three times that near the galactic poles. Very dif- 

 ferent is the result derived from the Herschelian gauges, which is this: 



Region....! II. III. IV. V. VI. VII. VIII. IX. 



Density ...107 154 281 560 2019 672 261 154 111 



From the gauges of the Herschels it follows that the galactic star- 

 density is nearly 20 times that of the galactic poles. At these poles the 

 Herschels counted about 50 per cent, more stars than Celoria. In the 

 galaxy itself they counted 14 for every one by Celoria. The principal 

 cause of this discrepancy is the want of uniformity of the magnitudes. 



The recent comparisons of the Durchmusterung with the heavens, 

 mostly made since Seeliger worked out the results we have given, 

 show that the limit of magnitude to which this list extends is far from 

 uniform, and varies with the star-density. In regions poor in stars, all 

 of the latter to the tenth magnitude are listed; in the richer regions of 

 the galaxy the list stops, we may suppose, with the ninth magnitude, or 



