314 ON ELECTRICAL ATTRACTIONS AND REPULSIONS. 



repelled toward the middle bell. These alternate motions 

 will be repeated as long as the conductor of the machine is 

 electrified." 

 Confirms These electric chimes form the strongest proof of my 



^^ inferences. Examine the action of the insulated balls. They 



are attracted first toward the lateral bells saturated with 

 this fluid t the middle bell, divested of superabundant elec- 

 tricity, and communicating with the ground, attracts to- 

 ward it the electricity taken from the machine by the balls, 

 and with it the balls themselves. This action may be com- 

 Electrical kite pared with that of an electrical kite, which, attracting the 

 electric fluid from a charged cloud, conveys it to the ground, 

 if a metallic wire serve it as a conductor. Place an appa- 

 ratus with two bells in the string of the electrical kite; one 

 communicating with the conducting wire of the kite by 

 means of a metal rod, the other insulated, but having a 

 communication from its inside to the ground like the middle 

 bell of the chimes : the moment the atmosphere has a charge 

 of electricity, the kite will occasion these chimes to act like 

 those of Mr. Libes, and gradually convey the electric fluid 

 from the clouds by their means as well as by a conductor.'* 

 After having given these live experiments as proofs of 

 two opposite actions, Mr. Libes finishes with these reflec- 

 tions on an experiment of Mr^ Grey. 



" These phenomena of electrical attraction and repulsion 

 led Grey to the idea of imparting to a body by means of 

 electricity an elliptical and at the same time rotatory mo- 

 tion. The following is a description of the apparatus he 

 employed, and the true object ol the experiment. 



6ik Experiment. 

 €tb experi- u F rom t| ie conductor of an electrical machine suspend 



a ring of stout brass wire about a foot in diameter. Beneath 

 this ring place a circular plate of metal, supported by 

 a- stand, so th;it you can bring it near enough to the ring 

 to prevent the glass balls, that will be mentioned, from 

 slipping between the ring and the plate. On the plate 

 place a ball of glass blczvn very thin, letting one point of its 

 circumference be in contact with the ring. If the appara- 

 tus be electrified, we shall see the ball animated at once with 



a rotatory 



