烟道孔

Floss \Floss\, n. [Cf. G. floss a float.]
1. A small stream of water. [Eng.]

2. Fluid glass floating on iron in the puddling furnace,
produced by the vitrification of oxides and earths which
are present.

{Floss hole}.
(a) A hole at the back of a puddling furnace, at which the
slags pass out.
(b) The tap hole of a melting furnace. --Knight.