e _pizzicato_ is, indeed,
oftenest heard from the double-basses, where it has a much greater
eloquence than on the violins. In music of a sombre cast, the short,
deep tones given out by the plucked strings of the contra-bass
sometimes have the awfulness of gigantic heart-throbs. The difficulty
of producing the other effects grows with the increase of difficulty
in handling the instruments, this being due to the growing thickness
of the strings and the wideness of the points at which they must be
stopped. One effect peculiar to them all--the most used of all
effects, indeed, in dramatic music--is the _tremolo_, produced by
dividing a tone into many quickly reiterated short tones by a rapid
motion of the bow. This device came into use with one of the earliest
pieces of dramatic music. It is two centuries old, and was first used
to help in the musical delineation of a combat. With scarcely an
exception, the varied means which I have described can be detected by
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