104 C. V. L. CHARLIER, 
rica in these dismal times make it, however, unlikely that an answer 
will reach me before this memoir goes to press. 
6) The value of ZA being determined, the position in space of 
each individual star of the spectral type B is directly deduced, It is 
found that the B-stars form an well defined cluster, which from a rela- 
tively dense centre gradually grows thinner till a distance of some 
200 Siriometers is reached, when no more stars are to be found. 
The centre of this cluster, which may be assumed to coincide 
with the centre of our stellar universe, is situated in a direction ¢=7."7, 
55°,6 in the constellation Carina. It lies in a part of the heaven 
which is described by Sir John HERSCHEL as one of the most beautiful 
in the sky. The distance of the centre from the sun amounts to 18.2 
Sir. The sun lies 4 Sir. above the XY-plane through the centre. 
The distribution of the B-stars follows a rather simple law. The 
frequeney distribution is, indeed, approximately a normal distribution 
of type 4. The dispersion in the principal plane (the XY-plane) amounts 
to 37.2 Sir. and is nearly the same in all directions of this plane. 
Perpendicularly to it the dispersion amounts to 13.1 Sir. The stellar 
universe (at least that of the B-stars) has an extension nearly three 
times as great in the plane of the Milky Way as perpendicularly to it. 
The density of the B-stars amounts to 0.002 stars per cub.-Sir. 
in the centre, The limit may be set down as some 200 Sir, in the 
XY-plane and to some 60 Sir, in the plane perpendicular to it, 
The pole of the Galaxy, as far as it is determined by the B-stars, 
lies at 
(17) a = 12120, d = 128074 
Ó = 
not far from the place usually adopted as the pole of the Milky Way. 
A galactie system of coordinates is introduced, having the Z-axis 
directed against the point (17). The X-axis is the projection of the 
direction from the centre to the sun on the galactie XY-plane. Its 
spherical coordinates (as seen from the sun) are 
a = 205.75, 0 = 470,50, 
a point in the constellation Cygnus. 
7) The number of B-stars, registered in the Annals of the Har- 
vard Observatory, is S04. The subclasses Bs and Be are then excluded 
