Mineralogie, Ardoises D'Anjou. Travail de la Carrierre Ouverte et Outils.
Revuell de Planches, sue Les Sciences, Les Arts Liberaux, et Les Arts Mechaniques, Avec Explication
, Diderot-D'Alembert. (Courtesy of NewsBank, Inc.)
![[Drawing] A drawing of a slate quarry in production as illustrated by Diderot in the Pictorial Encyclopedia of Science Art and Technology of 1762](slate4a.jpg "[Drawing] A drawing of a slate quarry in production as illustrated by Diderot in the Pictorial Encyclopedia of Science Art and Technology of 1762")