CONTENTS OF VOL. XLIX. — FIFTH SERIES. V 



Page 

 Lord Eavleigh on the Law of Eeciprocity in Diffuse Re- 

 flexion 324 



Proceedings of the Geological Society : — 



Mr. G. W. Lamplugh on some Effects of Earth - 

 movement on the Carboniferous Volcanic Eocks of 



the Isle of Man 325 



Miss Gertrude L. Elles on the Zonal Classification of 



the Wenlock Shales of the Welsh Borderland 326 



Mr. T. Stephens on an Intrusion of Diabase into Pen no- 

 Carboniferous Eocks at Frederick Henry Bay (Tas- 

 mania) . 328 



NUMBER CCXCIX.— APEIL. 



Messrs. H. Nagaoka and K. Honda on the Change of Volume 

 and of Length in Iron, Steel, and Nickel voids by Mag- 

 netization 329 



Prof. W. E. Ayrton and Mr. T. Mather on some Develop- 

 ments in the L T se of Price's Guard-Wire in Insulation 



Tes's 343 



Mr. T. J. Baker on the Frequency of Transverse Vibrations 



of a Stretched Indiarubber Cord 347 



Prof. Oliver Lodge on the Controversy concerning Volta's 



Contact Eorce 351 



Lord Blythswood and Dr. E. W. Marchant on the Echelon 

 Spectroscope ; with Application to Investigate the Beha- 

 viour of the chief Lines in the Mercury Spectrum under 



the Influence of a Magnetic Eield 384 



Prof. J. J. Thomson on Mr. Morris- Airey's Paper on Electro- 

 lytic Conduction in Gases ., 404 



Dr. A. Gait on the Heat of Combination of Metals in the 



Formation of Alloys , 405 



Notices respecting New Books : — 



F. Glanville Taylor's Introduction to the Differential and 



Integral Calculus and Differential Equations 411 



Science Abstracts, Physics aud Electrical Engineering. 



Vol.11., 1899 .. ..' 411 



Ch. Maurain's Le Magnetisme du Fer 412 



A. Cotton's Le Phcnomene de Zeeman 413 



