on the organ. The bombardon was the very
first bass wind instrument fitted with valves, and it was at first known
as the _corno basso_, _clavicor_ or _bass horn_ (not to be confounded
with the bass horn with keys, which on being perfected became the
ophicleide). The name was attached more to the position of the wind
instruments as bass than to the individual instrument. The original
corno basso was a brass instrument of narrow bore with the pistons set
horizontally. The valve-ophicleide in F of German make had a wider bore
and three vertical pistons, but it was only a "half instrument,"
measuring about 12 ft. A. Kalkbrenner, in his life of W. Wieprecht
(1882), states that in the Jager military bands of Prussia the corno
basso (keyed bass horn) was introduced as bass in 1829, and the
bombardon (or valve-ophicleide) in 1831; in the Guards these instruments
were superseded in 1835 by the bass tuba invented by Wieprecht and J.G.
Moritz.

The modern bombardon is made in two forms: the upright model, used in
stationary band music; and the circular model, known as the helicon,
worn round the body with the large bell resting on the left shoulder,
after the style of the Roman _cornu_ (see HORN), which is a more
convenient way of carrying this heavy instrument when marching. The
bombardon, and the euphonium, of which it is the bass, are the outcome
of the application of valves to the bugle family whereby the saxhorns
were also produced. The radical difference between the saxhorns and the
tubas (including the bombardon) is that the latter have a sufficiently
wide conical bore to allow of the production of fundamental sounds in a
rich, full quality of immense power. This difference, first recognized
in Germany and Austria, has given rise in those countries to the
classification of the brass wind as "half" and "whole" instruments
(_Halbe_ and _Ganze Instrumente_). When the brass wind instruments with
conical bore and cup-shaped mouthpiece first came into use, it was a
well-understood principle that the tube of each instrument must
theoretically be made twice as long as an organ pipe giving the same
note; for example, the French horn sounding the 8 ft. C of an 8 ft.
organ pipe, must have a tube 16 ft. long; C then becomes the second
harmonic of the series for the 16 ft. tube, the first or fundamental
being unobtainable. After the introduction of pistons, instrument-makers
experimenting with the bugle, which has a conical bore of very