Blowtube

n.
  1. A blowgun.
  2. A similar instrument, commonly of tin, used by boys for discharging paper wads and other light missiles.
  3. (Glassmaking) A long wrought iron tube, on the end of which the workman gathers a quantity of “metal” (melted glass), and through which he blows to expand or shape it; -- called also blowing tube, and blowpipe.