掏槽落煤法
Thirl \Thirl\, v. t. [imp. & p. p. {Thirled}; p. pr. & vb. n.
{Thirling}.] [See {Thrill}.]
To bore; to drill or thrill. See {Thrill}. [Obs. or Prov.]
That with a spear was thirled his breast bone.
--Chaucer.