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HISTORY 
ROYAL ASTRONOMICAL SOCIETY 
1820—1920 
EDITED BY 
J. L. E. DREYEK, M.A., Ph.D., D.Sc. 
PRESIDENT 1923- 
AND 
H. H. TURNER, M.A., D.Sc., D.C.L., F.R.S. 
PAST PRESIDENT 
SAVILIAN* PROFESSOR OF ASTRONOMY, OXFORD 
WITH CHAPTERS BY THEM AND BY 
R. A. SAMPSON, M.A., D.Sc., F.R.S. 
PAST PRESIDENT 
ASTRONOMER ROYAL FOR SCOTLAND 
The late Colonel E. H. GROYE-HILLS, C.M.G., D.Sc., F.R.S. 
PAST PRESIDENT 
H. F. NEWALL, M.A., D.Sc., F.R.S. 
PAST PRESIDENT 
PROFESSOR OF ASTROPHYSICS, CAMBRIDGE 
AND 
H. P. HOLLIS, B.A. 
FORMERLY ASSISTANT AT THE ROYAL OBSERVATORY, GREENWIOH 
PUBLISHED BY THE 
ROYAL ASTRONOMICAL SOCIETY 
BURLINGTON HOUSE, LONDON, W. 1 
AND SOLD BY 
WHELDON & WESLEY, LIMITED 
2, 3, & 4 ARTHUR STREET, NEW OXFORD STREET, LONDON, W.C. 2 
I 923