LIFE A ND LETTERS OF FARADAY. 303 



ators; they are also extremely bad conductors. The 

 moment we pass from the metals to their compounds we 

 pass from good conductors to bad ones, and from bad 

 radiators to good ones. Water, among liquids, is probably 

 the worst conductor; it is the best radiator. Silver, among 

 solids, is the best conductor; it is the worst radiator. The 

 excellent researches of MM. de la Provostaye and Desains 

 furnish a striking illustration of what I am inclined to 

 regard as a natural law that those atoms which transfer 

 the greatest amount of motion to the ether, or, in other 

 words, radiate most powerfully, are the least competent to 

 communicate motion to each other, or, in other words, to 

 propagate by conduction readily. 



CHAPTER XVIII. 



LIFE AND LETTERS OF FARADAY. 



1870. 



UNDERTAKEN and executed in a reverent and loving 

 spirit, the work of Dr. Bence Jones makes Faraday the 

 virtual writer of his own life. Everybody now knows the 

 story of the philosopher's birth; that his father was a 

 smith; that he was born at Newington Butts in 1791; that 

 he ran along the London pavements, a bright-eyed errand 

 boy, with a load of brown curls upon his head and a 

 packet of newspapers under his arm; that the lad's master 

 was a bookseller and bookbinder a kindly man, who 

 became attached to the little fellow, and in due time made 

 him his apprentice without fee; that during his apprentice- 

 ship he found his appetite for knowledge provoked and 

 strengthened by the books he stitched and covered. Thus 

 he grew in wisdom and stature to his year of legal manhood, 

 when he appears in the volumes before us as a writer of 

 letters, which reveal his occupation, acquirements, and 

 tone of mind. His correspondent was Mr. Abbott, a mem- 

 ber of the Society of Friends, who, with a forecast of his 

 correspondent's greatness, preserved his letters and pro- 

 duced them at the proper time. 



In later years Faraday always carried in his pocket a 

 blank card, on which he jotted down in pencil his thoughts 

 and memoranda. He made his notes in the laboratory, in 

 the theater, and in the streets. This distrust of his mem- 



