LEADING CONTENTS continued 



CHAPTER V 

 Galvanic and Voltaic Electricity 



CHAPTER VI 

 Electrical Mechanical Motion 



CHAPTER VII 

 The Electric Telegraph 



CHAPTER VIII 

 Electro-Magnetic Induction Its Origin and Generation 



CHAPTER IX 

 The Marvellous Utility of Electro-Magnetic Induction 



CHAPTER X 

 Ancient and Modern Systems of Wireless Telegraphy 



CHAPTER XI 



Hertz's Discovery of Electro-Magnetic Waves The Re- 

 searches of Dr Lodge and Lord Kelvin Popoff's 

 Invention of the ^Erial System Marconi's subsequent 

 adaptation of Popoff's Methods, &c. 



CHAPTER XII 



Popoff and Marconi Installations compared Marconi's 

 Attempt to Telegraph across the Atlantic with his ^Erial 

 System Professor Flemming's Opinion Adverse 

 Criticisms 



CHAPTER XIII 



Journalistic Reports re the Repeated Failures by Experi- 

 menters in their Efforts to Tune the Electric Currents, 

 &c., &c. 



CHAPTER XIV 



A Definition of the Word "Sound" as understood in a 

 Musical Sense Its Principal Attributes Matter Cap- 

 able and Incapable of producing Sound Untunable 

 Apparatus 



42 ESSEX STREET, STRAND, W,C. 



ii 



