io6 Nichols: Franklin's 



over a line of pack thread to a distance of 765 feet, and 

 having thus learned how to conduct the efifect to a dis- 

 tance they experimented upon the electrification of all 

 sorts of bodies, such as a load-stone, a red-hot poker, a 

 chicken, a soap bubble, a boy, suspended from the end 

 of their line. They also compared in a rough way the 

 electrification of a solid with that of a hollow body of 

 same material and found them as nearly as they could 

 judge to be alike. In 1734 Grey and Wheeler, working 

 in a dark room, observed the brush discharge from a 

 suspended metal rod which had been electrified, and 

 made some observations upon the electric discharge. 

 Speaking of electricity that year. Grey says: " It seems 

 to be of the same nature as thunder and lightning." 



In 1733 Charles Francis DuFay, a retired army officer, 

 and member of the Paris Academy, took up the study 

 of electricity. He repeated many of the experiments 

 of Grey and others, discovered the use of glass as an 

 insulator for his lines and found that the thread con- 

 ducted better when wet. DuFay announced the dis- 

 covery of two kinds of electricity, vitreous and resinous, 

 and the law of the repulsion of like and the attraction 

 of unlike charges. He was assisted in his experiments 

 by the Abbe Nollet, who became subsequently one of 

 the most prolific writers of the time upon the subject of 

 electricity. 



