those to whom they are not already familiar by watching the players
while listening to the music.

[Sidenote: _The viola._]

The viola is next in size to the violin, and is tuned at the interval
of a fifth lower. Its highest string is A, which is the second string
of the violin, and its lowest C. Its tone, which sometimes contains a
comical suggestion of a boy's voice in mutation, is lacking in
incisiveness and brilliancy, but for this it compensates by a
wonderful richness and filling quality, and a pathetic and inimitable
mournfulness in melancholy music. It blends beautifully with the
violoncello, and is often made to double that instrument's part for
the sake of color effect--as, to cite a familiar instance, in the
principal subject of the Andante in Beethoven's Fifth Symphony.

[Sidenote: _The violoncello._]

[Sidenote: _Violoncello effects._]

The strings of the violoncello (Plate II.) are tuned like those of
the viola, but an octave lower. It is the knee-fiddle (_viola da
gamba_) of the last century, as the viola is the arm-fiddle (_viola da
braccio_), and got its old name from the position in which it is held
by the player. The 'cello's voice is a bass--it might be called the
barytone of the choir--and in the olden time of simple writing, little
else was done with it than to double the bass part one octave higher.
But modern composers, appreciating its marvellous capacity for
expression, which is next to that of the violin, have treated it with
great freedom and independence as a solo instrument. Its tone is full