rs_, by H.S. de Blowitz, was published in 1903.

BLOWPIPE, in the arts and chemistry, a tube for directing a jet of air
into a fire or into the flame of a lamp or gas jet, for the purpose of
producing a high temperature by accelerating the combustion. The
blowpipe has been in common use from the earliest times for soldering
metals and working glass, but its introduction into systematic chemical
analysis is to be ascribed to A.F. Cronstedt, and not to Anton Swab, as
has been maintained (see J. Landauer, _Ber_. 26, p. 898). The first work
on this application of the blowpipe was by G. v. Engestrom, and was
published in 1770 as an appendix to a treatise on mineralogy. Its
application has been variously improved at the hands of T.O. Bergman,
J.G. Gahn, J.J. Berzelius, C.F. Plattner and others, but more especially
by the two last-named chemists.

The simplest and oldest form of blowpipe is a conical brass tube, about
7 in. in length, curved at the small end into a right angle, and
terminating in a small round orifice, which is applied to the flame,
while the larger end is applied to the mouth. Where the blast has to be
kept up for only a few seconds, this instrument is quite serviceable,
but in longer chemical operations inconvenience arises from the
condensation of moisture exhaled by the lungs in the tube. Hence most
blowpipes are now made with a cavity for retaining the moisture.
Cronstedt placed a bulb in the centre of his blowpipe. Dr Joseph Black's
instrument consists of a conical tube of tin plate, with a small brass
tube, supporting the nozzle, inserted near the wider end, and a
mouth-piece at the narrow end.

The sizes of orifice recommended by Plattner are 0.4 and 0.5 mm. A
trumpet mouth-piece is recommended from the support it gives to the
cheeks when inflated. The mode of blowing is peculiar, and requires some
practice; an uninterrupted blast is kept up by the muscular action of
the cheeks, while the ordinary respiration goes on through the nostrils.

If the flame of a candle or lamp be closely examined, it will be seen to
consist of four parts--(a) a deep blue ring at the base, (b) a dark cone
in the centre, (c) a luminous portion round this, and (d) an exterior
pale blue envelope (see FLAME). In blowpipe work only two of these four
parts are made use of, viz. the pale envelope, for oxidation, and the
luminous portion, for reduction. To obtain a good _oxidizing flame_, the
blowpipe is held with its nozzl