

CONTENTS OF VOL. XXVII. SIXTH SERIES. V 



NUMBER CLIX.— MARCH. 



Page 



Dr. F. P. Kerschbamn : Interference Experiments in a 

 Highly Rarefied Gas. (Plate VI.) 397 



Dr. A. M. Tyndall and Mr. H. G. Hughes on Cathode Dis- 

 integration in a Vacuum Tube 415 



Prof. A. Gray: Notes on Electricity and Magnetism.— 

 1. The " Rails and Slider " Magneto-machine. 2. Perma- 

 nent Magnets and Dynamical Theory 428 



Lord Rayleigb : Further Calculations concerning the 

 Momentum of Progressive Waves 436 



Dr. W. F. G. Swann on the Expression for the Electrical 

 Conductivity of Metals as deduced from the Electron 

 Theory 441 



Prof. A. van den Broek on Nuclear Electrons 455 



Mr. C. R. Englund on the Electron Atmosphere (?) of 

 Metals . . 457 



Prof. E. P. Worley on the Decline of the Hypothesis of Ionic 

 Dissociation 459 



Prof. Dr. E. Waetzmann : A Note on Prof. E. H. Barton's 

 Article "Range and Sharpness of Resonance under Sus- 

 tained Forcing and their Variations with Pitch " 467 



Mr. G. H. Livens on the Intrinsic Optical Activity of Iso- 

 tropic Media , 468 



Mr. A. LI. Hughes on the Long- Wave Limits of the Normal 

 Photoelectric Effect 473 



Prof. H. Konen on the Distribution of Energy in the Spectra 

 of Gases 475 



Prof. 0. W. Richardson on the Theory of Photoelectric and 

 Photochemical Action 476 



Sir E. Rutherford on the Structure of the Atom 488 



Mr. C. G. Darwin on Collision of a Particles with Light Atoms. 499 



Dr. N. Bohr on the Effect of Electric and Magnetic Fields on 

 Spectral Lines 506 



Prof. R. W. Wood: Separation of Close Spectrum Lines for 

 Monochromatic Illumination. (Plate VII.) 524 



Prof. R. W. Wood on the Production of a very intense 

 Sodium Flame 530 



Prof. R. W. Wood and Mr. W. P. Speas on a Photometric 

 Study of the Fluorescence of Iodine Vapour 531 



Proceedings of the Geological Society 538 



NUMBER CLX.— APRIL. 



Prof. J. W. Nicholson on the High-frequency Spectra of 

 the Elements, and the Structure of the Atom 541 



Prof. E. Taylor Jones on Induction - Coil Potentials. 

 (Plate VIII.) 565 



