ipe
fashion, and its voice is peculiarly impressive and noble. It is a
favorite solo instrument in Liszt's symphonic poems.

[Sidenote: _Lips and reeds._]

[Sidenote: _The brass instruments._]

[Sidenote: _Improvements in brass instruments._]

[Sidenote: _Valves and slides._]

The fundamental principle of the instruments last described is the
production of tone by vibrating reeds. In the instruments of the brass
choir, the duty of the reeds is performed by the lips of the player.
Variety of tone in respect of quality is produced by variations in
size, shape, and modifications in parts like the bell and mouth-piece.
The _forte_ of the orchestra receives the bulk of its puissance from
the brass instruments, which, nevertheless, can give voice to an
extensive gamut of sentiments and feelings. There is nothing more
cheery and jocund than the flourishes of the horns, but also nothing
more mild and soothing than the songs which sometimes they sing. There
is nothing more solemn and religious than the harmony of the
trombones, while "the trumpet's loud clangor" is the very voice of a
war-like spirit. All of these instruments have undergone important
changes within the last few score years. The classical composers,
almost down to our own time, were restricted in the use of them
because they were merely natural tubes, and their notes were limited
to the notes which inflexible tubes can produce. Within this century,
however, they have all been transformed from imperfect diatonic
instruments to perfect chromatic instruments; that is to say, every
brass instrument which is in use now can give out all the semitones
within its compass. This has been accomplished through the agency of
valves, by means of which differing lengths of the sonorous tube are
brought within the command of the players. In the case of the
trombones an exceedingly venerable means of accomplishing the same end
is applied. The tube is in part made double, one part sliding over the
other. By moving his arm, the player lengthens or shortens the tube,
and thus changing the key of the instrument, acquires all the tones
which can be obtained from so many tubes of different lengths. The
mouth-pieces of the trumpet, trombone, and tuba are cup-shaped, and
larger than the mouth-piece of the horn, which is little else than a
flare of the slender tube, sufficiently wide to receive enough of the
player's lips to form the embouchure, or human reed, as it might here
be n