CONTENTS OF VOL. XIX. 



(SIXTH SERIES)! V 



- — i. ' - 



* t 

 NUMBER CIX.— JANUARY 1910. 



Pago 

 Mr. William Sutherland on the Fundamental Constant of 



Atomic Vibration and the Nature of Dielectric Capacity . . 1 



Mr. William Sutherland on Molecular Diameters 25 



Mr. E. Gold on the Relation between Periodic Variations of 



Pressure, Temperature, and Wind in the Atmosphere. ... 26 

 Mr. Harold G. Savidge: Tables of the ber and bei and 



ker and bei Functions, with further Formula? for their 



Computation 49 



Mr. J. S. Dow on the Physiological Principles underlying 



the Flicker Photometer 58 



Dr. J. W. Nicholson on the Effective Resistance and ■ 



Inductance of a Helical Coil 77 



Dr. C. V. Burton : Note on a Gravitational Problem 91 



Lord Rayleigh on the Regularity of Structure of Actual 



Crystal's 96 



Dr. Walter Makower and Dr. Sidney Russ on the Recoil of 



Radium C from Radium B 100 



Mr. W. A. Scoble on Ductile Materials under Combined 



Stress (Plate I.) 116 



Prof. Alexander McAulay on the Spontaneous Generation 



of Electrons in an Elastic Solid .Ether 129 



Dr. Geo. A. Campbell on Telephonic Intelligibility 152 



Dr. T. H. Havelock on the Instantaneous Propagation of 



Disturbance in a Dispersive Medium 160 



Mr. Norman Campbell on the Principles of Dynamics 168 



Mr. Norman Campbell on the ^Ether 181 



Prof. E. Rutherford on the Action of the a Rays on 



Glass 192 



Mr. P. V. Be van on the Absorption Spectrum of Potassium 



Vapour. (Plate II.) ] 95 



Mr. E. M. Wellisch on the Theory of the Small Ion in 



Gases 201 



Dr. Alexander Russell on Alternating Current Spark 

 . Potentials 203 



