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La distribution de Ia lamiere galactique by tlie author, (1903); there- 

 for we had only to accept that the diffused light of the Milky Way 

 in the middle areas ( — T to -{- 2° gal. /3) is equally distributed. 



A detailed discussion of these tables and of the curves which 

 are constructed by means of them (üg, 2) would lead us too far. 

 We shall only draw the attention to the following points : 



The general smoothness and the small values of the ordinates of 

 the curve belonging to table VIII B, southern hemisphere, can cer- 

 tainly not lead to the conclusion that the nebulae in the southern 

 galaxy proper are indeed much sparser and more uniformly scattered. 

 It is remarkable that about 110° gal. longitude, even within the 

 galaxy proper the density of faint nebulae nearly equals their average 

 number in the entire northern hemisphere (8.5 and 10.0). 



If we consider the general shape of the curves for the density of 

 the nebulae we perceive a certain contrast with the curves of table 

 IX for the galactic light — as compared with the minimum of IX the 

 maximum of VII seems somewhat displaced towards 90^ — but in 

 the details no complementary shape can be detected. 



The most remarkable feature of the nebulaecurves is a strong 

 maximum about 100" to 110" in the northern and in the southern 

 hemisphere, which seems to find its counterpart, at least in the 

 northern gal. hemisphere, 180 degrees further on at about 280°. 



If in the neighbourhood of the galactic zone the space occupied 

 by nebulae extended equally far in all directions from the sun 

 (which, with the suppositions we have made, would mean that 

 the nearest agglomerations of stars in that plane do not lie at greatly 

 varying distances) and if within that space the distribution of those 

 nebulae were almost uniform, there would be no reason why the 

 curves of VII and VIII show considerable maxima and minima. 



We know, however, that the nebulae show a strong tendency to 

 occur in "streams" and "nests", hence in the details their distribution 

 must be very irregulai-. Consequently the peculiar positions of the 

 principal maxima of the curves might be explained by accepting one 

 or more nebular streams, running from 100° to 280° gal. longitude 

 somewhat obliquely towards the galactic plane. Obviously this 

 supposition is arbitrary. 



Another acceptable explanation is that the region of the nebulae, 

 viz. the extra-galactic region, extends in and near the galactic plane 

 farther in the direction 100° towards 280° than in other directions; 

 in other words: that in the direction mentioned the galactic aggrega- 

 tions of stars are lying at greater distances. 



It deserves attention that the line which in space connects the 



