File:Franklin - Sentry-Box Experiment.jpg

Benjamin Franklin’s sentry-box experiment.

Drawing reproduced from the “Bowdoin MS”, which consists of a manuscript copy of all of Franklin’s earliest papers on electricity, copied by two amanuenses and corrected by Franklin, and sent by Franklin to Bowdoin in 1750.

Cf. I. Bernard Cohen, The Two Hundredth Anniversary of Benjamin Franklin's Two Lightning Experiments and the Introduction of the Lightning Rod, in: Proceedings of the American Philosophical Society, Vol. 96, No. 3. (Jun. 20, 1952), pp. 331–366.

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