v i CONTENTS. 



CHAPTER XII. 



PAGE. 



On Crystalline and Slaty Cleavage , 232 



CHAPTER XIII. 

 On Paramagnetic and Dianiagnetic Forces 244 



CHAPTER XIV. 

 Physical Basis of Solar Chemistry 250 



CHAPTER XV. 

 Elementary Magnetism 261 



CHAPTER XVI. 

 On Force , 281 



CHAPTER XVII. 

 Contributions to Molecular Physics 294 



CHAPTER XVIII. 

 Life and Letters of Faraday , 303 



CHAPTER XIX. 

 The Copley Medalist of 1870 320 



CHAPTER XX. 

 The Copley Medalist of 1871 325 



CHAPTER XXI. 

 Death by Lightning 332 



CHAPTER XXII. 

 Science and the Spirits 336 



CHAPTER XXIII. 

 Reflections on Prayer and Natural Law 342 



CHAPTER XXIV. 

 Miracles and Special Providences 348 



CHAPTER XXV. 

 On Prayer as a Form of Physical Energy 371 



CHAPTER XXVI. 

 Vitality .376 



