14 



C. V. L. Chailier 



8. Having computed for each cluster the values of •/], C from formulae (9^ 

 the rectangular coordinates x, y, z ai'e obtained according to the formulae 



, 100 



M9\ 100 



(12) iy=ri — c, 



^ 100 

 a 



Here denotes the apparent diameter of the clustet. As to s it is a certain 

 constant, the same for all clusters, permitting to transform the coordinates into 

 absolute measure (siriometers). Let us call s the scale. 



For deternjining the scale we maj^ proceed in the following way. 



From the individual values of x\z, ?/ : e , z-.z we compute their mean values 

 and their dispersions. Let us first consider their mean values. We get 



MV- \ = — 0.944 + 0.931 



31 — 1.479 + 0.893 



Mi^-j = ^ 0.187 ± 0.123. 



From these numbers we deduce the mean values of the anti-centre coordinates 



= — 1.764 ± 0.900, 



(13) . ilf •-) = -f 0.014 + 0.900, 



3I{"-]= ^ 0.187 ± 0.123. 



These values determine the centre of the system of the clusters. The deter- 

 mination is rather uncertain, especially in the y- and ^-coordinate, but we may 

 conclude that the centre has a very small ^-coordinate and that the x-coordinate 

 of the centre has the value 



— 1.7B4 £. 



We find that the centre of tlie clusters lies in the same direction as the centre 

 of the B-stars. As, moreover, both objects are nearly symmetrically distributed 

 relatively to the galactic plane we have all reason to consider their centres to 

 coincide. In Meddel., Ser. II, N:o 14 I have got for the centre of the .ß-stars the 

 a;-coordiuate — 17.77 siriometers, so that the scale, s, is determined from the equation 



1.754 £ = 17.77 



or 



(14) e= 10.13 sir. 



