IV 
CONTENTS. 
NO. PAGE 
XIV. Notes on the Atmospheric Electrical Potential Gradient in 
the Industrial Districts around Leeds. By Dan. W. Steuart 
and Ingvar Jorgensen. Communicated by James A. S. 
Watson, B.Sc., ...... 202 
{Issued separately July 15, 1914.) 
XV. On the Hall and the Transverse Thermomagnetic Effects and 
their Temperature Coefficients. By F. Unwin, M.Sc., Assis- 
tant Lecturer in Physics, Heriot-Watt College, Edinburgh. 
Communicated by Professor F. G. Baily, . . . 208 
{Issued separately , 1914.) 
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