280 



"Journal of Experiments, April, 1773 



N. i 

 N. 2 



Weight 



7-6 

 6-6 5 



Cent. grav. 

 from pin 



5-36 

 5-285 



35'i 

 136-1 



N. I N. 2 



Force requisite to separate straws without wires 40-8 



with wires 159^9 



Therefore force required to separate heavy electrometer falls short of four 

 times force required to separate light electrometer in the ratio of 296 to 303-6, 

 or of I to 1-027. 



568] Separation of Henry's electrometer by different strengths of electrification. 



Nairne's jar being tried against the two trial plates for plate H, the pith 

 balls separated a little after a short time the same way as the two trial plates. 

 Therefore Nairne's jar is supposed to contain about of plate H, or 16 times 

 as much as plate M. 



The two conductors of Nairne were set end to end with [Henly's] electro- 

 meter on furthest, and the jar applied to the same, the furthest conductor 

 being without any point, and the plate M was placed near it, set on a conductor 

 communicating with the ground. When the electrometer was raised a little 

 above 90, the nearest conductor was removed and the electricity of globe 

 taken away. Then as soon as the electrometer was sunk to 90 a communication 

 was made between conductor and plate M and immediately taken away again, 

 and the figure to which the electrometer sunk wrote down and the electricity 

 of plate M discharged, after which a communication was again made between 

 the conductor and plate M. 



The results of the experiments are contained in the following Table, where 

 the first^column is the number of times that a communication has been made 

 between the conductor and M. 



