In some places wash applied with half-dry brush and/or rubbed with a finger.

Rembrandt van Rijn (Dutch, 1606-1669). Woman Leaning on a Window Sill, dated ca. 1638. Pen and brown ink, brown wash, on light brown prepared paper. 6 11/16 x 4 15/16 in. (17 x 12.5 cm).
Fondation Custodia, Collection Frits Lugt, Paris