Paris, Panckoucke; Liège, Plomteux, 1784-1785. Two (of three) volumes in two. Large 4to (25.6 x 19.6 cm). 1,603 pp. [cxiv, 722; 787], 16 plates. Contemporary quarter calf over mottled boards. Spines with red morocco labels with gilt title. Marbled edges.

The first two volumes of the rare mathematics section of the famous ' Encyclopédie'. A detailed collation is as follows: Volume 1 (1784) title to the ' Encyclopédie', title to the 'Mathematiques', cxiv pp. (Discours préliminaire), pp. 1-721 [A-EXT; actually Abaissement-Extrème], [i] (errata); Volume 2 (1785), title to the 'Encyclopédie', title to the volume; pp. 1-787 (FAC-ROU; actually Face-Rudolphines). Lacking is Volume 3 (1789). Still later, two more parts on mathematical games and game-theory were published. These are exceedingly rare. Bindings worn, a few spots; otherwise a very good set of the first two (of three) volumes.