30 



C. V. L. Charlier 



the rectangular anti-centre-coordinates x', «/', z which are obtained from the spherical 

 coordinates through multiplying by the scale e, which is found to be 



£ = 1.60. 



The determination of the scale will be discussed in the paragraph 17. 



The following table gives in col. 1 the galactic square, in col. 2 the number 

 in the N. G. C. in col. 3 and 4, right ascension and declination (1900) of the cluster 

 according to Bailey, in col. 5, G, 7 the spherical galactic coordinates, in col. 8 and 

 9 the galactic longitude and latitude obtained from ■/], C by the formulae 



tg? = 7j:^; sin?; = C. 



In col. 10 is given the diameter of the cluster according to Bailey, in col. 11 the 

 number of stars in col. 12 the limits in the observed magnitude from the same 

 autority, furthermore in col. 13, 14, 15 the rectangular anti-centre-coordinates in 

 siriometers, in col. 16 the distance in siriometers. In coliunn 18 I give the Messier 

 number of the cluster and the description of Bailey from the Harvard photographs. 



16. On the plates V and VI the projection of the clusters on the coordinate 

 planes is shown. The distribution of the clusters is highly striking. Considering 

 first the distribution in the plane of the Milky Way (the XF-plane), we remark that 

 the clusters form a rather well limited group extended from us almost exclusively 

 in one direction, tlie negative F-axis (= 0|)hiuchus and Sagittarius). For only 5 

 the F-coordinate is positive. It is to be observed that the clusters are not, as 

 could be expected, crowded round the centre of the Galax}^, as it has been deter- 

 mined from the I?-stars, a position confirmed by the distribution of the clusters. 

 This centre lies from us in the direction of the negative X-axis and the principal 

 direction of the globular clusters lies almost exactly perpendicular to the X-axis. 

 In the XZplane we find a similar distribution. Considering at last the distribution 

 in the FZ'-plane we find a remarkable condensation of the clusters round the F-axis. 

 The globular clusters evidently form a group of bodies nearly having the form of 

 a prolate ellipsoid, the axis of rotation (= the longer axis) coinciding with the F-axis. 



It is to be remarked that there are 8 clusters for which no values of x , y 

 and z have been given in table 2. For these the diameter is either ver}'^ small 

 ( < 1') or unknown, being in the latter case also very small. According to our re- 

 marks in § 4 we have no right to consider the distance as inversely proportional 

 to the appannit diameter for very small values of the apparent diameter. These 8 

 clusters have therefore not been taken into consideration in the computation of the 

 characteristics of the distribution. In the diagrams these 8 clusters have been 

 placed at the mean distance of the clusters in the different directions. 



The mean values and the dispersions of the coordinates have the following 

 values, where I have left the scale s undetermined 



