CONTENTS {continued). 



Preliminary Determination of the Wave -lengths of the Hydrogen Lines, 

 derived from Photographs taken at Ovar at the Eclipse of the Sun, 

 1900, May 28. By F. W. Dyson, M.A., Sec. B.A.S. Communicated by 

 W. H. M. Chsistie, C.B., M.A., F.E.S 33 



On the Brightness of the Corona of January 22, 189S. Preliminary i?"ote. . 

 By H. H. Tubnee, D.Sc, F.K.S., Savilian Professor \ 36 



The Boiling Point of Liquid Hydrogen, determined by Hydrogen and Helium 

 Gas Thermometers. By James Dewae, M.A., LL.D., Professor of 

 Chemistry at the Koyal Institution, and Jacksouian Professor, University 

 of Cambridge 44, 



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