Charles BONNET (1720–1793), Swiss naturalist and philosopher. Autograph letter, “De ma Retraite,” June 28, 1787, to M. de Latourrette, permanent secretary of the Royal Academy of Sciences and Letters of Lyon; 1½ pages, quarto, addressed. He expresses his gratitude for the remedy sent for his wife: “Her ailments are long-standing, and for more than 28 years they have been testing her patience and mine.” He has read the Academy’s program, which proposes “the Question of Newtonian Optics” as the subject for the Prize. “I would like to think that the Academy would not award a prize to an anti-Newtonian work, and your kind letter confirms that I was not mistaken. This young François, whose name I do not know, and who has been honored by two famous academies, is undoubtedly a very distinguished scholar, from whom we can expect even greater works”…