[ 401 ] ^ 



LXIII. defections on the Inadeqtiacy oflhe principal Hypotheses 

 to account for ike Phcenomena of Electricity. 



[Continued iVom page 350.] 



About the year 1733, M. Du Faye, having electrified and re- 

 pelled a piece of gold-leaf by means of excited glass, attempted 

 to repel it still further with "excited copal; but contrary to his 

 expectation an attraction took place. Surprised at this dis- 

 covery he persevered in his investigation, and observed that *the 

 gold-leaf when repelled by glass was attracted as well by sealing- 

 wax, resin, or sulphur. 



From these experiments he drew the follow ing conclusion : 

 " that there are two distinct kinds of electricity very different 

 from one another," one of which is found in glass, rock crystal, 

 &c. the other in amber, copal, silk, and many other substances. 

 He supposed that each fluid repelled itself, while it attracted 

 the other; and affirmed that "from this principle one may 

 easily deduce the explanation of a great number of phaenomena." 

 Du Faye, however, after some time relinquished his opinion of 

 two electric fluids, and subscribed to that of Dr. Franklin. 



In 1757 Mr. Eeles commenced a series of connnunications, 

 which he affirms were transmitted to the Royal Society. In 

 these papers the author revived Du Faye's discarded opinion of 

 two electric fluids, but modified and extended it so considerably 

 that it might be almost called a new hypothesis. He applied it 

 to the explanation of the principal phaenomena, thus bringing hi-T 

 doctrines to a degree of perfection which Du Faye had not at- 

 tempted. From some unknown causes it happened that Mr* 

 Eeles's papers were never published in the Transactions of the 

 Royal Society. 



In 1759 an account of some experiments by Mr. Symmer 

 was read at the Royal Society, from which the author conceived 

 that the existence of two fluids was rendered probable. He sup- 

 posed that these fluids by contrasting and counteracting each 

 other produced the phaenomena of electricity; that they are 

 essentially different from each other ; that they both exist com- 

 bined in matter, and when in quantities sufficient to balance 

 each other that they do not manifest properties ; but when one 

 or other exceeds that, the accumulated power exerts its pro- 

 perties. 



In 1767 appeared Priestley's History of Electricity, which 

 professed to give an account of the principal hypotheses that 

 had ever been promulgated. Under the consideration of two 

 electric fluids, the Doctor adverts to the hypothesis of Du 



Vol.44. No. 200. Dec. 1814. C c Faye 



