The penciling technique is created by adjusting the nozzle to a straight stream pattern and using series of short bursts of water directed at burning materials. This helps reduce the production of flammable gases by cooling the burning walls and ceiling below their ignition point.
• (n.) The work of the pencil or bruch; as, delicate penciling in a picture. • (p. pr. & vb. n.) of Pencil • (n.) Lines of white or black paint drawn along a mortar joint in a brick wall.
Black lines dividing the tan on the toes.
Pen'cil·ing noun [ Written also pencilling .] 1. The work of the pencil or bruch; as, delicate penciling in a picture. 2. (Brickwork) Lines of white or black paint drawn along a mortar joint in a brick wall. Knight. 
Black lines dividing the tan on the toes.