476 Scientific Proceedings, Boyal Dublin Society. 



to exist, the evidence in favour of an absorptive medium will be 

 proportionally strengthened. 



In conclusion, I am well aware that the data on which I have 

 proceeded are not sufficiently reliable to warrant very positive 

 conclusions on the subject, though I think the Table which I have 

 constructed exhibits in at least two respects — the great rise after 

 the first set, and the subsequent steady decline — features which can 

 hardly be ascribed to insufficient or erroneous observations. I am 

 likewise aware that I have only attacked one branch of the question. 

 of star-distribution — the distances of the star-masses as. distinct 

 from their directions. But notwithstanding this, I believe that 

 the views which I have put forward are in some respects new, and 

 that they possess a basis of truth ; which will, I trust, be a suf- 

 ficient apology for laying them before a meeting like the present. 



