From Sir John Pringle
AL: Historical Society of Pennsylvania
Monday evening [December, 1773? 6]
Mean while Dr. P. returns Dr. F. the French letter which he was to shew to C. Castries [?]. He sends him a small piece upon Electricity, sometime ago sent to Dr. P. from Germany, but which Dr. P. has not yet perused: Also sends Dr. F. the first sheet of his 4to edition in order for giving the measure to the intended Vignette.7
6. Pringle enclosed a proof page of his pamphlet, A Discourse on the Different Kinds of Air … (London, 1774). He had delivered the discourse, as president of the Royal Society, at the presentation of the Copley Medal to Priestley on November 30, 1773; the pamphlet was reviewed the following February in the Gent. Mag., XLIV (1774), 81. This note was therefore written between the end of November and the publication date, and December seems a likely time.
7. We cannot identify the French letter. As for Castries, if our reading of the name is correct, it is tempting to think he was the son of the marquis de Castries, minister of marine during part of BF’s French mission; but unfortunately the young man (he was seventeen) was known as the comte de Charlus, and we have no evidence that he had recently been in England or Pringle in France. The “small piece” on electricity was, we assume, that which Ingenhousz mentioned in his letter to BF below, May 12, 1774. The vignette was a printer’s decoration on the first page of the Discourse; Sir John presumably wanted BF’s professional opinion.