Gallery admission is free
Open daily 10:00-18:00, Thursday-Friday until 21:00
Shading or filling in with finely spaced parallel lines. When more sets of parallel lines are drawn criss-cross over the first it is known as cross-hatching.
Other techniques and materials
Mark Gertlerpossibly by Dora Carringtoncirca 1909-1911NPG 5431
National Portrait Gallery, St Martin's Place, London, WC2H 0HE
Switchboard: +44 (0) 20 7306 0055