558 Mechanical Philosophy. [Chap. I. 



afterwards generally received throughout the scien- 

 tific \^'orld ; and, though by no means without op- 

 position, still continues to hold a more extensive 

 influence than any other. 



Electricity seems to have been first applied to 

 medical purposes by Mr. Kratzenstein, professor 

 of medicine at Halle, in 1744. From that period 

 it gradually grew into notice, by means of the ex- 

 periments of the abbe Nollet, Jallabert of Ge- 

 neva, Sauvages of Montpellier, Bohadsch of 

 Prague, Dr. Watson before mentioned. Dr. Frank- 

 lin, and many others. The medical virtues of this 

 wonderful fluid soon excited attention and inquiry 

 throughout the scientific world. And although 

 the repetition of experiments, which has been con- 

 stantly going on from that period to the present, 

 has served to correct many errors into which the 

 enthusiastic fell in the beginning; yet electricity, 

 ^fter undergoing many revolutions of fashion, is 

 now well established as an important article of the 

 Materia Medica. 



After the interesting discoveries of Dr. Frank- 

 lin, the next great experimenters and discoverers 

 in electricity were Mr. Canton of Great Britain, 

 signor Bcccaria of Italy, and Mr. Wilcke of Ger- 

 many, w ho considerably enlarged the sphere of our 

 knowledge respecting the conducting powers of 

 different substances, and threw farther light on 

 t\\Q plus and minus states of electrics. The doc- 

 trine of Franklin, that these two states arise from 

 a redundancy or deficiency of the same matter, 

 was but little opposed, until 17»59, when Mr. Sym- 

 mer, an English philosopher, revived the ideas of 

 du Fay, w.ith .squic new .modifications of his own» 



