able to be used on the concert platform. (Editor's
note.)]

The xylophone is a species of harmonica composed of strips or
cylinders of wood, struck with two little hammers. It produces a
clattering sound, both powerful and piercing.

To complete this catalogue of sounds mention should be made of the
strings playing _col legno_, that is with the wood or back of the bow.
The sound produced is similar to the xylophone, and gains in quality
as the number of players is increased.

A table is appended showing the range of the celesta, _glockenspiel_
and xylophone.

Percussion instruments producing indefinite sounds.

Instruments in this group, such as triangle, castanets, little bells,
tambourine, switch or rod (_Rute._ Ger.), side or military drum,
cymbals, bass drum, and Chinese gong do not take any harmonic or
melodic part in the orchestra, and can only be considered as
ornamental instruments pure and simple. They have no intrinsic
musical meaning, and are just mentioned by the way. The first three
may be considered as _high_, the four following as _medium_, and the
last _two_ as deep instruments. This may serve as a guide to their use
with percussion instruments of determinate sounds, playing in
corresponding registers.

Comparison of resonance in orchestral groups and combination of
different tone qualities.

In comparing the resonance of the respective groups of
sound-sustaining instruments we arrive at the following approximate
conclusions:

In the most resonant group, the brass, the strongest instruments are
the trumpets, trombones and tuba. In loud passages the horns are only
one-half as strong, 1 Trumpet = 1 Trombone = 1 Tuba = 2 Horns.
Wood-wind instruments, in _forte_ passages, are twice as weak as the
horns, 1 Horn = 2 Clarinets = 2 Oboes = 2 Flutes = 2 Bassoons; but, in
_piano_ passages, all wind-instruments, wood or brass are of fairly
equal balance.

It is more difficult to establish a comparison in resonance between
wood-wind and strings, as everything depends on the number of the
latter, but, in an orchestra of medium formation, it may be taken for
granted that in _piano_ passages, the whole of one department (_all_
1st Violins or _all_ 2nd Violins etc.) is equivalent in strength
to one wind instrument, (Violins I = 1 Flute etc.), and, in _forte_
passages, to two wind instruments, (Violins I = 2 Flutes = 1 Oboe + 1
Clarinet, etc.).

It is still harder to form a comparison with instruments