In shipbuilding the chisel shown is known as a 'slice'.
Salaman describes it thus: 'A very broad flat chisel with a blade 2-4'' wide and up to about 30'' overall length and with a slightly rounded cutting edge. The socketed handle is offset to keep the hand clear when paring a flat surface and sometimes terminates in a knob for pushing. Used for fairing and removing waste from the deck and elsewhere, particularly in places where the adze cannot reach. At HM Dockyard Portsmouth (1969) a slice with a 14'' handle was used for clearing tar and dirt from the sheave-slots of ships' blocks.'