Ornament 

This ornamental design, created by Master AD, an anonymous artist working in the 16th century, is an example of a pattern book, a collection of designs for various decorative purposes. The intricate, swirling patterns in black ink against a light brown background are characteristic of the Mannerist style, known for its emphasis on elaborate, often asymmetrical designs. These patterns could have been used for various decorative purposes, such as textiles, furniture, or architecture. The artist's initials "AD" are subtly included in the design, adding a personal touch to this intricate and decorative piece.