XV 



April 28, 1904 



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



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

 ordered for them. 



The Royal Medal awarded to Sir David Gill, in 1903, was handed 

 to the recipient by the President. 



The following Papers were read : — 



I. "Further Experiments on the Production of Helium from 

 Radium." By Sir William Ramsay, K.C.B., F.R.S., and 

 F. Soddy. 



II. " The Effects of Changes of Temperature on the Modulus of 

 Torsional Rigidity of Metal Wires." By Dr. F. Horton. 

 Communicated by Professor J. J. Thomson, F.R.S. 



III. " The Sparking Distance between Electrically-charged Surfaces. 



Preliminary Note." By Dr. P. E. Shaw. Communicated 

 by Professor J. H. Poynting, F.R.S. 



IV. "Studies on Enzyme Action. Part II. — The Rate of the 



Change conditioned by Sucro-clastic Enzymes, and its Bear- 

 ing on the Law of Mass Action. Part III. — The Influence 

 of the Products of Change on the Rate of Change conditioned 

 by Sucro-clastic Enzymes." By Dr. E. F. Armstrong. 

 Communicated by Professor II. E. Armstrong, F.R.S. 



V. "Studies on Enzyme Action. Part IV. — The Sucro-clastic 

 Action of Acids as contrasted with that of Enzymes." By 

 Dr. E. F. Armstrong and R. J. Caldwell. Communicated 

 by Professor H. E. Armstrong, F.R.S. 



VI. "Enzyme Action as bearing on the Validity of the Ionic- 

 Dissociation Hypothesis, and on the Phenomena of Vital 

 Change." By Professor H. E. Armstrong, F.R.S. 



VII. " On the Changes of Thermo-electric Power produced by Mag- 

 netisation, and their Relation to Magnetic Strains." By 

 Dr. S Bidwell, F.R.S. 



VIII. "The Behaviour of the Short-Period Atmospheric Pressure 

 Variation over the Earth's Surface." By Sir Norman 

 Lockyer, K.C.B., F.R.S., and Dr. W. J. S. Lockyer. 



