What is a sort of electroscope, invented by Rousseau, in which the dry pile is employed to measure the amount of electricity transmitted by different bodies, or to determine their conducting power. Nichol called?

diagometer — A sort of electroscope, invented by Rousseau, in which the dry pile is employed to measure the amount of electricity transmitted by different bodies, or to determine their conducting power. Nichol. (Webster's 1913.)

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