Chap, i.] Experiments of Du Fay. 30 i 



very vigoroufly by the head of the boy. He found 

 alfo, that he could communicate electricity to fluid 

 bodies, by infulating them upon a cake of rofm ; and 

 obferved, that when an excited tube was held over a 

 cup of water, the water was prefently attracted, in a 

 conical form, towards the tube ; that the electic matter 

 paffed from the tube to the water with a flight flafh 

 and a crackling noife -, -and that the fluid fubfided with 

 a tremulous and waving motion. 



After this period the fpirit of philofophy in this 

 branch was no longer confined to England. M. Du 

 Fay, intcndant of the French king's gardens, added to 

 the (lock of difcoveries. He found that all bodies, 

 except metallic, foft, and fluid ones, might be made 

 electric by firft heating them, and then rubbing them 

 on any fort of cloth. He alfo excepts thofe fub- 

 ilances which grow foft by heat, as gums, or which 

 diflblve in water, as glue. In purfuing Mr. Grey's 

 experiments with a packthread, &c. he perceived thau 

 they fucceeded better by wetting the line. To prove 

 the effects of this wonderful agent on the animal body, 

 he fufpended himfelf by filk cords, as Mr. Grey had 

 fufpended the boy, and in this fituation he obferved, 

 that as foon as he was electrified, if another perfon 

 approached him, and brought his hand, or a metal 

 rod, within an inch of his body, there immediately 

 iflircd from it one or more prickling (hoots, attended 

 with a fnapping noife j and he adds, that this experi- 

 ment occafioned a fimilar fenfation in the perfon who 

 placed his hand near him : in the dark he obferved, 

 that thefe ihappings were occafioned by fo many fparks 

 of fire. 



Mr. Grey, on rerunning his experiments, imme- 

 diately concluded from that of M. Du Fay, in which 

 a piece of metal drew fparks from the perfon elec- 

 trified, 



