CONTENTS. 



PAGE 



ELECTRICAL UNITS OF MEASUREMENT .... 73 



A Lecture delivered at the Institution of Civil En- 

 gineers, May 3, 1883. 



THE SORTING DEMON OF MAXWELL 137 



Abstract of a Friday evening Lecture before the Royal 

 Institution of Great Britain, Pebruary 28, 1879. 



ELASTICITY VIEWED AS POSSIBLY A MODE OF 



MOTION 142 



Abstract of a Friday evening Lecture before the Royal 

 Institution of Great Britain, March 4, 1 88 1. 



THE SIZE OF ATOMS 147 



Friday evening Lecture before the Royal Institution of 

 Great Britain, February 3, 1883. 



STEPS TOWARDS A KINETIC THEORY OF 



MATTER 218 



Opening Address to the Mathematical and Physical 

 Section of the British Association, Montreal Meet- 

 ing, 1884. 



THE SIX GATE WAYS OF KNOWLEDGE 253 



Presidential Address to the Birmingham and Midland 

 Institute, October 3, 1883. 



THE WAVE THEORY OF LIGHT 300 



A Lecture delivered under the auspices of the Franklin 

 Institu'e, Philadelphia, U.S.A., September 29, 1884. 



