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SYDNEY CHAPMAN, B.A., D.SC, F.R.A.S., ON 



greatest possible good grace and willingness, and I think we are very 

 deeply indebted to him on this special account, seeing that he had 

 so short a time to prepare the paper for us. We owe a further 

 great indebtedness to him in that he has given us the very latest 

 results of his own special work. It was only at the last meeting of 

 the Eoyal Astronomical Society that Dr. Chapman read a paper on 

 the Total Light of the Stars, a subject which he has included in the 

 address to which we have just listened. 



The work from which Dr. Chapman has derived the results which 

 he has given us this afternoon has been an extremely toilsome one ; 

 it has involved not only the counting of the star images in five 

 thousand areas, carefully distributed over the heavens, but it has 

 meant the creation of standards of stellar magnitude for each order 

 of magnitude under examination, and the estimation of the magni- 

 tude of every star image examined. Our debt, therefore, to 

 Dr. Chapman is exceedingly great, both for the self-sacrificing way 

 in which he has come forward to supply our need, for the interest, 

 the value and the freshness of the information which he has given 

 us, and for the admirably clear way in which he has presented it. 



The Astronomer Royal (Dr. F. W. Dyson) said that the last 

 time he had had the pleasure of hearing an address in that hall it 

 had been one given by the late Sir David Gill, who was, he believed, 

 one of their Honorary Correspondents. He could not help thinking 

 as he listened to Dr. Chapman's address how pleased Sir David 

 would have been to hear of the progress that had been made, and 

 was still being made, in this particular branch of astronomy, and he 

 could imagine how delighted he would have been with the account 

 which Dr. Chapman had just given of the results which had been 

 obtained — largely from an enterprise which Sir David himself had 

 originally inspired — in this interesting and difficult subject of the 

 dimensions of the stellar universe. He thought that they were 

 warranted in saying that there was on the whole a general agree- 

 ment amongst astronomers that the universe of stars was bounded : 

 it did not stretch out infinitely. They had now a definite idea as to 

 the number and extent of the stars, and their knowledge concern- 

 ing them was comparable with, but nothing like so accurate as, their 

 knowledge of the solar system. Modern astronomers were largely 

 concerned with the problem of finding out some analogy to the 

 bright points of light that the stars present to us. The point of 



