Charles François de Cisternay Du Fay

French chemist

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Charles François de Cisternay Du Fay was a French chemist who, in 1733, proposed that electricity consisted of two fluids: "vitreous" (positive) and "resinous" (negative). He observed that when a glass rod was electrified, it attracted nearby cork bits. However, if the rod touched the cork, the cork bits were repelled by each other. Du Fay explained this by suggesting that matter is normally neutral, containing equal amounts of both fluids. Friction could separate these fluids, leading to attraction or repulsion between objects based on their resulting imbalance. While Benjamin Franklin later proposed a one-fluid theory, Du Fay's two-fluid concept is considered essentially correct in that fundamental particles possess both positive and negative charges.12

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thermionic power converter
Development of thermionic devices
…early as the mid-18th century, Charles François de Cisternay Du Fay, a French chemist, noted that electricity may be conducted in the gaseous matter—that is to say, plasma—adjacent to a red-hot body. In 1853 the French physicist Alexandre-Edmond Becquerel reported that only a few volts were required to drive electric…
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…early as the mid-18th century, Charles François de Cisternay Du Fay, a French chemist, noted that electricity may be conducted in the gaseous matter—that is to say, plasma—adjacent to a red-hot body. In 1853 the French physicist Alexandre-Edmond Becquerel reported that only a few volts were required to drive electric…
Read More