Drawing Techniques: a Guide
Liquid Media: Brush and Wash  

Brushes have been in use for both writing and drawing since antiquity. Artists favored brushes made from tufts of squirrel hair mounted in the hollow end of a quill. They were used for a large range of strokes, from fine lines to broad fields of wash.

Artists often combined brown inks with washes of a different color, especially grey, as here, or blue. They also made washes from ground red chalk and used them together with red chalk as a linear medium for rich effect.

  Stefano della Bella, Allegory of the North Wind
Metal Nib Pen