Benjamin Franklin (1706-1790) [Wikipedia]
One Kinds of Electrical Fluids: Positive (+) and Negative (-) Electricity
1747 [Secondary Source]
(ed.) Robert G Fuller
A Love of Discovery. Science Education--The Second Carrier of Robert Karplus
(Kluwer Academic, New York, NY, 2002) pp. 288-290.

[Primary Source]
Benjamin Franklin
Letter to Peter Collinson (July 11, 1747)
Wonderful Effect of Points.---Positive and Negative Electricity.---Electrical Kiss.---Counterfeit Spider.---Simple and commodious Electrical Machie.
Jared Sparks
The Works of Benjamin Franklin. Volume V.
(Hilliard, Gray, and Co., Boston, 1840) p. 181-188.
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