8 FOREWORD. 



but, like other great men, he made mistakes. It 

 would be unwise to accept and perpetuate what is 

 untrue. 



The author hopes that he will succeed in interest- 

 ing the reader, and again cause him to be enraptured 

 with the wondrous work of nature. If the same 

 feeling is aroused of pleased and awed amazement at 

 the exceeding and marvellous beauty of it all, as has 

 been felt by him while thinking and writing, he will 

 not have published his thoughts in vain. 



Newton thought that electricity, and gravitation 

 and magnetism might possibly be but manifestations 

 of one great controlling power pervading all nature. 

 Faraday searched, throughout his whole life, for 

 this power in vain. It has been discovered (in 

 material motion, and its results of electricity, 

 magnetism, gravitation, etc.) by the author, and 

 proved in this book and by experiment. 



