ELECTRICITY. 



or discharged of their electricity, by being put in metallic communication with 

 the ground. These general facts he proved by direct experiment. 



He placed two persons, A. and B., on insulating supports. In the hand of 

 A. he put a glass tube, which being rubbed by A. became electrified. This 

 tube was then touched at every part of the rubbed surface by B. ; after which 

 the same process was several times repeated, the tube being deprived of its > 

 electricity as often as it was touched by B. A third person, C., not insulated, 

 now presented his ringer or a metallic sphere to B., from whom a spark was 

 drawn ; and by repeating this, or by touching the person of B., the latter was 

 deprived of the electricity he had received from the tube. This was no more 

 than was expected. But on subjecting A. to the same process, the very same 

 effects were produced. It appeared, therefore, that both A. and B. were elec- 

 trified. 



Being again electrified, as before, by the friction of the tube, instead of A. 

 and B. being successively touched by C., they were made to touch each other, 

 both remaining insulated. After this both were found to be as completely 

 de-elcctrised and restored to their ordinary state as when they had been touched 

 by C. 



A cork ball, suspended by a silk thread, being electrified by contact with the 

 excited glass tube, was repelled when brought near the person of B., but it was 

 attracted when brought near the person of A. 



From these experiments it appeared the electrical states of A. and B. were 

 different. Franklin called the state of B., and consequently that of the glass 

 tube from which he drew the electricity, positive and that of A. negative. The 

 one was said to be positively, the other negatively electrified. The cloth with 

 which A. rubbed the glass tube was, like A., negatively electrified it attracted 

 the cork ball ; and the glass tube, like B., was positively electrified it re- 

 pelled the cork ball. 



The generality of this result was established by a great variety of experi- 

 ments. In all cases it appeared that the opposite electrical charges of the two 

 bodies submitted to friction, or of any insulated bodies in communication with 

 them, had the same reciprocally neutralizing power ; in virtue of which, when 

 brought into contact, or when a metallic communication was established be- 

 tween them, all signs of electricity would disappear. 



Such is a strict statement of the facts as evolved in the experiments. The 

 hypothesis proposed by Franklin for their explication was as follows : All 

 bodies in their natural state are charged with a certain quantity of electricity, 

 in each body this quantity being of definite amount. This quantity of elec- 

 tricity is maintained in equilibrium upon the body by an attraction which the 

 particles of the body have for it, and does not therefore exert any attraction 

 for other bodies. But a body may be invested with more or les? electricity 

 than satisfies its attraction. If it possess more, it is ready to give i,p the surplus 

 to any body which has less, or to share it with any body in its natural state ; 

 if it have less, it is ready to take from any body in its natural state a part of its 

 electricity, so that each will have less than their natural amount. A body 

 having more than its natural quantity is electrified positively or plus, and one 

 which has less is electrified negatively or minus. 



When two bodies are submitted to mutual attrition and oecome electrified, 

 one parts with a portion of its proper electricity, which is received by the 

 other. The latter then has more than its natural amount, and is positively elec- 

 trified ; the former has less, and is negatively electrified. 



In the instance above stated, when A. rubs the glass tube, he loses a portion 

 of his natural electricity, and is negatively electrified ; while the tube receives 

 what he loses, and becomes positively electrified. When B. touches the tube, 



