CONTENTS 



THE THIRD VOLUME. 



THE MECHANICO-CHEMICAL SCIENCES. 



BOOK XI. 

 HISTORY OF ELECTRICITY. 



"f,AGE 



Introduction . ' 5 



CHAPTER I. DISCOVERY OF THE LAWS OF ELECTRIC 



PHENOMENA . . . . -9'' 



CHAPTER II. THE PROGRESS OF ELECTRICAL THEORY . 21 



Question of one or two Fluids 37 



Question of the Material Reality of the Electric Fluid . 40 



BOOK XII. 

 HISTORY OF MAGNETISM. 



CHAPTER I. DISCOVERY OF THE LAWS OF MAGNETIC 



PHENOMENA . . . .49 



CHAPTER II. PROGRESS OF MAGNETIC THEORY . . 55 

 Theory of Terrestrial Magnetism . . . . .62 

 Conclusion ........ 64 



BOOK XIII. 



HISTORY OF GALVANISM, OR VOLTAIC ELECTRICITY. 

 CHAPTER I. DISCOVERY OF VOLTAIC ELECTRICITY . . 79 



CHAPTER II. RECEPTION AND CONFIRMATION OF THE DIS- 

 COVERY OF VOLTAIC ELECTRICITY . . 85 



CHAPTER III. DISCOVERY OF THE LAWS OF THE MUTUAL 

 ATTRACTION AND REPULSION OF VOLTAIC CURRENTS. 

 AMPERE 89 



VOL. III. a 



