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}.
Note: It is called a mouth blowpipe when used with the mouth;
but for both chemical and industrial purposes, it is
often worked by a bellows or other contrivance. The
common {mouth blowpipe} is a tapering tube with a very
small orifice at the end to be inserted in the flame.
The {oxyhydrogen blowpipe}, invented by Dr. Hare in
1801, is an instrument in which oxygen and hydrogen,
taken from separate reservoirs, in the proportions of
two volumes of hydrogen to one of oxygen, are burned in
a jet, under pressure. It gives a heat that will
consume the diamond, fuse platinum, and dissipate in
vapor, or in gaseous forms, most known substances.
{Blowpipe analysis} (Chem.), analysis by means of the
blowpipe.
{Blowpipe reaction} (Chem.), the characteristic behavior of a
substance subjected to a test by means of the blowpipe.