2. Casket covered with stamped leather, cuir bouilli. German, 14th Century.
FIG. 2, FIG. 3.—INCISING KNIFE USED DOWNWARDS LIKE A PENCIL
Thin skins should rarely be cut, and, if they are cut, the incision should barely penetrate the surface. On ox-hide the depth of the cut may be considerable without danger of impairing the strength of the leather.
FIG. 4, FIG. 5.—INCISING KNIFE USED UPWARDS