stons are used simultaneously the length of the air column is
automatically adjusted to the theoretical length required to ensure
correct intonation. (5) Victor Mahillon's automatic regulating pistons
(_pistons regulateur automatique_) produced about 1886, the result of
independent efforts in the same direction as Blaikley, and equally
ingenious and effectual.[19] Finally we have (6) more recently the
_Besson enharmonic valve system_ (fig. 3) with three pistons and six
independent tuning slides which give the seven positions independently,
thus realizing in a simple effectual manner all that Sax strove to
accomplish with his six pistons. The enharmonic valves give all notes
theoretically true; there are in addition separate means for adjusting
each of the first six lengths, for although these lengths are
theoretically correct there are always certain modifying conditions
connected with brass instruments which render it essential to provide
means for adjustment. All notes being true on this Besson cornet, they
can be fingered to the greatest advantage for smoothness and rapidity.
(7) Rudall, Carte & Co.'s cornet (fig. 4), with strictly conical bore
(Klussmann's patent) throughout the open tube and additional lengths
from the mouthpiece to the bell, gives a perfect intonation and is at
the same time easy to blow. There are no crooks to this cornet when
constructed in B[flat], but it may be instantaneously transposed into
the key of A major by means of an undetachable slide guided by a piston
rod. (V. M.; K. S.)

FOOTNOTES:

[1] See Marin Mersenne, _L'Harmonie universelle_ (Paris, 1636-1637),
bk. v., pp. 273-274.

[2] See Eisel's (Anon.) _Musicus [Greek: Autodidaktos], oder der sich
selbst informirende Musicus_ (Erfurt, 1738), p. 93 and table vi.

[3] Sebastian Virdung, _Musica getutscht und auszgezogen_ (Basel,
1511).

[4] Michael Praetorius, _Syntag. Music._, vol. ii. _De Organographia_
(Wolfenbuttel, 1618), pp. 25 and 41, pls. 8 and 13.

[5] See Mersenne, _loc. cit._

[6] See Ad. MS. 30342, Brit. Museum, fol. 145. A tract in French
containing pen and ink sketches of musical instruments, which dates
from the 17th or perhaps the 18th century, and was formerly in the
possession of the Jesuit college in Paris. Here the _pedalle_ is the
bass pommer, or _hautbois_, and the sackbut is indicated as second
bass or _basse-contre_. As also in Mersenne, the cornets are c