dial. and techn. [f. KNOB sb.]
a. To knock, etc.; spec. = KNAP v.1 2, KNOB v. 3. b. Metallurgy. To shingle; also NOBBLE, q.v.
1842–76. Gwilt, Archit. (ed. 7), Gloss., Knobbling, knocking off the rough protuberances of hard rock stone at the quarry.
1863–9. Dict. Archit., Knobbling, the term used near London and in the west of England for … reducing a mass of stone in the quarry to a somewhat square block…. In flint work it is called ‘knapping.’
1876. Whitby Gloss., Knobble, v. to strike with a club.
1879. Miss Jackson, Shropsh. Word-bk., Knobble, to hammer; to knock, but not forcibly.
1881. Raymond, Mining Gloss., Knobbling-fire, a bloomary for refining cast-iron.
