IV CONTENTS OF VOL. XXVIII. FIFTH SERIES. 



NUMBEE CLXXI.— AUGUST. 



Page 



Lord Bayleigh on Achromatic Interference-Bands 77 



Mr. A. W. Clayden on some Photographs of Lightning and of 



" Black " Electric Sparks 92 



Mr. J. T. Bottomley on Expansion with Eise of Temperature 



of Wires under Pulling Stress. (Plate IX.) 94 



Messrs. Louis Duncan, Gilbert Wilkes, and Gary T. Hutchin- 

 son on a Determination of the Yalue of the B.A. Unit of 

 Eesistance in Absolute Measure, by the Method of Lorenz. 98 

 Dr. H. H. Hoffert on Intermittent Lightning-Plashes. 



(Plate IV.) 106 



Mr. E. T. Glazebrook on the Eeflexion and Eefraction of Light 

 at the Surface of a Crystal on the Quasi-labile iEther 



Theory 110 



Prof. H. Hertz on the Propagation of Electric Waves through 



Wires , 117 



Prof. E. J. Anderson on an Apparatus Illustrating Crystal 



Eorms. (Plate II.) 127 



Mr. E. W. Smith on a Shunt-Transformer 132 



Mr. A. W. Ward on the Use of the Biquartz in determining 



the position of the Plane of Polarization 134 



Notices respecting New Books : — 



Dr. J. Casey's Treatise on Spherical Trigonometry, and 



its application to Geodesy and Astronomy 138 



Proceedings of the Geological Society : — 



Major-Gen. C. A. McMahon on the Hornblende Schists 



and Banded Crystalline Eocks of the Lizard 139 



Mr. T. Eoberts on the Upper Jurassic Clays of Lincoln- 

 shire ". 140 



Mr. J. E. Kilroe on the Origin of Movements in the 



Earth's Crust 141 



Prof. J. Prestwich on the Eelation of the Westleton Beds 

 or Pebbly Sands of Suffolk to those of Norfolk ...... 142 



Mr. E. Eutley on Tachylyte from Victoria Park, White- 

 inch, near Glasgow 143 



Mr. H. G. Lyons on the Bagshot Beds and their Strati- 

 graphy 144 



On the Kinetics of Bodies in Solution, by W. Nernst 145 



On the Molecular Condition of Dissolved Iodine, by Morris 



Loeb 146 



Some Observations on the Passage of Electricity through Gases 



and Vapours, by Dr. Natterer 147 



On the Electrical Eesistance of Insulators at High Tempera- 

 ture, by Dr. H. Koller 147 



On the Eesistance to Disruptive Discharge offered by Gases 



under High Pressures, by Max Wolf 148 



The Nature of Solutions, by Prof. S. U. Pickering 148 



