= DSB X, p.330-342. "Les Pensées, dans cette édition, sont augmentées, dit l'éditeur, non seulement d'un grand nombre de pensées, mais encore de plusieurs morceaux très considérables, qui n'avaient jamais été imprimés » (Quérard). First collected edition of Pascal's works, bringing together Pascal’s literary, philosophical, and scientific works and including a number of texts that had not previously appeared in print (or had only been privately issued in extremely rare forms), such as: the Pascal-Noël correspondence on the vacuum; Letter to Le Pailleur refuting Noël - Pascal’s reply to Noël’s critique on the vacuum; Preface to Pascal’s Traité du vide - The only surviving fragment of the major intended treatise on the vacuum; Correspondence with Pierre de Fermat and de Ribeyre - Important letters on mathematics and scientific inquiry; Pascal’s texts on his calculating machine - Including his explanations, letters (e.g., to Queen Christina), royal patents, and finely engraved plates depicting the mechanism. These were extremely rare in their original printings and became widely available here; Écrits sur la grâce - Texts on grace and theological reflections that had not previously been published. The works also includes Pascal’s important published works such as "Pensées" (religious and philosophical fragments), "Lettres provinciales", and other essays and letters and all Pascal's texts relating to his invention of the calculating machine, with two engraved plates depicting its technique. Lower pastedowns with 20th cent. owner's ticket. Attractive set.