xiv INTRODUCTION 



to enhance the importance of a study of electro- 

 statics. Not long ago our brilliant and lamented 

 friend, G. F. FitzGerald, used chaffingly to speak 

 of electrostatics as " one of the most beautiful and 

 useless adaptations of nature " ; and it was becoming 

 the custom with teachers, who felt that they must 

 attend exclusively to the practically useful and not 

 waste their students' time on decoration and super- 

 fluities, almost to ignore, or at any rate to scamper 

 through, the domain of electrostatics, and to begin 

 the study of electricity with the phenomena of 

 current, especially with the connection between 

 electricity and magnetism. 



And certainly from the severely practical point 

 of view, as well as from many other aspects, this 

 part of electrical science remains the most impor- 

 tant ; but to him who would not only design 

 dynamos and large-scale machinery, to him who, in 

 addition to the training and aptitude of the 

 engineer, possesses something of the interests, the 

 instinct, and the insight, of a man of science, to 

 such a one the nature and properties of an electric 

 charge, at "rest and in motion, constitute a fascinat- 

 ing study ; for there lies the key to the inner 

 meaning of all the occurrences with which his active 

 life is so intimately concerned there lies the 

 proximate solution of problems which have excited 

 the attention and taxed the ingenuity of philo- 

 sophers and physicists and chemists for more than 

 a century. Indeed it turns out that subjects 



