stria[3] what is known as the cylinder action is largely
used; for the piston or pump is substituted a four-way brass cock
operated by means of a key and a series of cranks.

In order to obtain a complete chromatic scale throughout the compass,
there must be, as on the slide-trombone, seven different positions or
lengths of tubing available, each having its harmonic series. These
different lengths are obtained on the bombardon by means of a
combination of pistons: the simultaneous use of Nos. 2 and 3 lowers
the pitch two tones; of Nos. 1, 2 and 3, three tones; of Nos. 1, 2, 3,
4, five and a half tones, &c. A combination of pistons, however, fails
to give the interval with an absolutely correct intonation, since the
length of tubing thrown open is not of the theoretical length required
to produce it. Many ingenious contrivances have been invented from
time to time to remedy this inherent defect of the valve system, such
as the six-valve independent system of Adolphe Sax; the Besson
_Registre_, giving eight independent positions; the Besson
compensating system _Transpositeur_; the Boosey automatic compensating
piston invented by D.J. Blaikley, and V. Mahillon's automatic
regulating pistons. More recently the Besson enharmonic valve system,
with six independent tuning slides and three pistons, and Rudall,
Carte & Company's new (Klussmann's patent) bore, conical throughout
the open tube and additional lengths, have produced instruments which
leave nothing to be desired as to intonation. (See VALVES and TUBA.)
(K. S.)

FOOTNOTES:

[1] See Dr E. Schafhautl's article on Musical Instruments, section 4
of _Bericht der Beurtheilungscommission bei der Allg. deutschen
Industrie-Ausstellung_, 1854 (Munich, 1855), pp. 169-170; also
Friedr. Zamminer, _Die Musik und die Musikinstrumente in ihrer
Beziehung zu den Gesetzen der Akustik_ (Giessen, 1855), p. 313.

[2] V.C. Mahillon, _Elements d'acoustique musicale et instrumentale_
(Bruxelles, 1874), p. 153.

[3] The bombardon is used in the military bands of Austria, but in
those of Germany it has been superseded by a bass tuba differing
slightly in form and construction from the bombardons and bass tubas
used in England, France, Belgium and Austria.

BOMBAY CITY, the capital of Bombay Presidency, and the chief seaport of
western India, situated in 18 deg. 55' N. and 72 deg. 54' E. The ci