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Sunlight at Southall Green. Dr. Ingen Housz discovers photosynthesis
Abstract:
In the following fictitious conversation, Dr. Jan Ingen Housz (1730-1799), the Dutch physician and natural philosopher, describes to William Temple Franklin (1760-1823), the grandson of Benjamin Franklin, how in 1779 he discovered the paramount role of sunlight in what we now call photosynthesis (Wiesner 1905; Van der Pas 1981; Reed 1949; Beale and Beale 1999). The two men, together with the English law reformer Samuel Romilly, were dinner guests of the First Marquis of Lansdowne at Lansdowne House on Wednesday 2 February 1791 (Bowood House Archives 1791). As far as possible we use their own recorded words and phrases, employing surviving manuscripts as a lexicon. Additional biographical and geographical details are provided in an Appendix, and all sources are listed in the References.
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