132 



Dr. Frank Watson Dyson 



[April 24, 



"We may take it that the formula substantially represents the 

 observed facts. AYith the proper motions distributed according to 

 this formula and the actual velocities distributed according to the 

 law of errors, the distribution of the stars in distance may be deter- 

 mined. AVhen this is done we find that these 1247 stars are distri- 

 buted in space in the following manner : — 



The most remarkable feature of this table is that 70 per cent of 

 the stars lie between the narrow limits of 100 and 400 parsecs. 



I have treated the 470 stars brighter thaa 10™'0 in a similar 

 manner, and also the 148 stars brighter than O'^'O. Combining the 

 separate results it is found that the stars are distributed in space as 

 shown in the following table : — 



Table V. — Number of Solae Staes (Types F and G) 



AT DlFFEEENT DISTANCES. 



