IV CONTENTS OE VOL. XXXVIII. SIXTH SERIES. 



Page 



Notices respecting New Books : — 



Prof. W. C. M C C. Lewis's A System of Physical Chemistry. 197 



A. Eindlay's Osmotic Pressure 198 



G. H. Livens's The Theory of Electricity 199 



Annuaire du Bureau des Longitudes pour l'an 1919. . . . 200 



Intelligence and Miscellaneous Articles : — 



Problems in Conduction of Heat, by H. S. Carslaw .... 200 



NUMBER CCXXIV.— AUGUST. 



Prof. A. Gray on Electric and Magnetic Eield Constants 

 and their Expression in terms of Bessel Functions and 

 Elliptic Integrals 201 



Dr. Norman Campbell on Time-Lag in the Spark Discharge. 214 



Dr. T. J. I'a. Bromwich on approximations in the Theory 

 of Probabilities 231 



Mr. R. F. Grwyther on the Equations for Material Stresses, 

 and their formal solution 235 



Mr. D. L. Hammick on Latent Heat and Surface Energy. — 

 Parti 240 



Mr. A. T. Mukerjee on a Method of Measuring the Capacity 

 of Gold-leaf Electroscopes 245 



Mr. L. C. Jackson : Mathematical Investigation of the Sta- 

 bility of Dr. A. W. Stewart's Atom 256 



Proceedings of the Geological Society : — 



Mr. II. Hansford Worth on the Geology of the Meldon 

 Valleys, near Okehampton, on the Northern Verge 

 of Dartmoor 267 



NUMBER CCXXV.— SEPTEMBER. 



Prof. L. Natanson on the Molecular Theory of Refraction, 

 Reflexion, and Extinction 269 



Mr. S. K. Mitra on the Large-Angle Diffraction by Apertures 

 with Curvilinear Boundaries. (Plate IV.) 289 



Prof. W. M. Hicks on the Value of the Silver Oun 301 



Prof. W. E. Adeney and Mr. H. G. Becker on the Determi- 

 nation of the Rate of Solution of Atmospheric Nitrogen 

 and Oxygen by Water. Part I. (Plate V.) 317 



