CONTENTS OF VOL. XIV. 



(SIXTH SERIES). 



NUMBER- LXXIX.— JULY 1907. 



Pa ° e 

 Mr. W. Sutherland on Ionization in Solutions and Two 



New Types of Viscosity 1 



Mr. J. H. C. Searle on the Effect of Rotatory Inertia on the 



Vibrations of Bars 35 



Lord Rayleigh on the remarkable Case of Diffraction Spectra 

 described by Prof. Wood 60 



Messrs. K. Honda and T. Terada on the Effect of Stress on 

 Magnetization and its Reciprocal Relations to the Change 

 of Elastic Constants by Magnetization. (Plates I.-V.) . . 65 



Mr. A. Stephenson on the Eorcing of Oscillations by Distur- 

 bances of Different Frequencies 115 



Mr. S. H. Burbury on Diffusion of Grases as an Irreversible 

 Process 122 



Mr. W. L. Upson on the Electric Arc. (Plates VI. & VII.) 120 



Prof. R. W. Wood on the Magnetic Rotation of Sodium 

 Vapour at the D Lines. (Plate VIII.) 145 



Lord Rayleigh on the Passage of Sound through Narrow Slits. 153 



Prof. P. Lowell on a General Method for Evaluating the 

 Surface-Temperature of the Planets ; with special reference 

 to the Temperature of Mars 161 



Prof. A. Stanley Mackenzie on Secondary Radiation from a 

 Plate exposed to Rays from Radium 176 



Prof. R. A. Millikan and Mr. Gr. Winchester on the Influence 

 of Temperature upon Photo-electric Effects in a Very High 

 Vacuum, and the Order of Photo-electric Sensitiveness of 

 the Metals . . 188 



Mr. Gr. A. Schott : Note on the Explanation of the Radio- 

 activity of Radium 210 



Prof. W! Wien on Rays of Positive Electricity 212 



