3 books on Logic / Mathematics: Augustus de Morgan, Formal Logic: Or, The Calculus of Inference, Necessary and Probable, 1847, first edition, hardcover, rebound in full calf binding, Taylor and Walton, London, 336 pp. TOGETHER WITH Willard van Orman Quine, A System of Logistic, 1934, first edition, hardcover, red cloth, Harvard University Press. First printing of Quine's first book. AND Henri Lebesgue, Lecons sur les Series Trigonometriques, 1906, first edition, French text, Gauthier-Villars, Paris, this one deaccessioned from a regional institution and includes a letter of deaccession from the institution. Good candidates for repair and rebinding. Morgan in Good condition, heavy loss to the leather on the boards, contents with some light foxing throughout. Quine binding in poor condition, with heavy staining, loss and edgewear likely from insect and/or rodent damage. Small stain to foredge of last few pages, otherwise a clean and unmarked copy. Lebesgue in very poor condition, boards detached, spine broken, text-block loose, and with ex-library marks. Merchandise will be packed and transported by the purchaser at their own risk and expense. A list of recommended shippers is on our website: https://www.conceptgallery.com/auctions/shipping/ .