Cuir bouilli n. In decorative art, boiled leather, fitted by the process to receive impressed patterns, like those produced by chasing metal, and to retain the impression permanently.
... of Euboea accustom their horses to carry sacks which they can at pleasure fill with air, and which in case of need they carry instead of the girth of the saddle above and at the side, and they are well covered with plates of cuir bouilli, in order that they may not be perforated by flights of arrows. Thus they have not on their minds their security in flight, when the victory is uncertain; a horse thus equipped enables four or five men to cross over at ... — The Notebooks of Leonardo Da Vinci, Complete • Leonardo Da Vinci