xxi 



June, 16, 1904. 



Sir WILLIAM HUGGINS, K.C.B., O.M., President, in the Chair. 



The Eight Hon. Donald Alexander Smith, Baron Strathcona, was 

 balloted for and elected a Fellow of the Society. 



Dr. Alexander Muirhead was admitted into the Society. 



A List of the Presents received was laid on the table, and thanks 

 ordered for them. 



The following Papers were read : — 



I. " The Origin and Growth of Bipple-mark." By (Mrs.) Hertha 

 Ayrton. Communicated by Professor W. E. Ayrton, 

 F.E.S. 



II. " On the Seismic Effect of Tidal Stresses." By E. D. Oldham. 

 Communicated by Professor J. W. Judd, C.B., F.E.S. 



III. " On Flame Spectra." By C. de Watteville. Communicated 



by Professor A. Schuster, F.E.S. 



IV. "An Experiment illustrating Harmonic Undertones." By H. 



Knapman. Communicated by Dr. G. J. Burch, F.E.S. 



V. "A Probable Cause of the Yearly Variation of Magnetic Storms 

 and Aurorae." By Sir Norman Lockyer, K.C.B., F.E.S., 

 and Dr. W. J. S. Lockyer. 



VI. " On the Eelation between the Spectra of Sun-spots and Stars." 

 By Sir Norman Lockyer, K.C.B., F.E.S. 



VII. " On the Action of Wood on a Photographic Plate in the Dark." 

 By Dr. W. J. Eussell, F.E.S. 



VIII. " The Eetardation of Combustion by Oxygen." By Professor # 

 H. E. Armstrong, F.E.S. 



IX. " The Absorption and Thermal Evolution of Gases occluded in 

 Charcoal at Low Temperatures." By Professor J. Dewar, 

 F.E.S. 



X. " Direct Separation of the Most Volatile Gases from Air without 

 Liquefaction." By Professor J. Dewar, F.E.S. 



XL " On the Influence of the Time Factor on the Correlation between 

 Barometric Heights at Two Stations 1,000 Miles apart." 

 By Miss F. E. Cave-Browne-Cave, Communicated by 

 Professor K. Pearson, F.E.S. 



