of little
sustaining power, for too great a diversity in production and emission
of sound exists. The combined force of groups of sustained resonance
easily overpowers the strings played _pizz._ or _col legno_, the piano
played softly, or the celesta. As regards the _glockenspiel_, bells,
and xylophone, their emphatic tone will easily prevail over other
groups in combination. The same may be said of the kettle-drums with
their ringing, resounding quality, and also of other subsidiary
instruments.

The influence of the timbre of one group on another is noticeable when
the groups are doubled; for instance, when the wood-wind timbre is
closely allied to the strings on the one hand, and to the brass on the
other. Re-inforcing both, the wind _thickens_ the strings and
_softens_ the brass. The strings do not blend so well with the brass,
and when the two groups are placed side by side, each is heard too
distinctly. The combination of the three different timbres in unison
produces a rich, mellow and coherent tone.

All, or several wind instruments in combination will absorb one
department of added strings:

2 Fl. + 2 Ob. + Vns I,
or: 2 Ob. + 2 Cl. + Violas,
or: 2 Cl. + 2 Fag. + 'Cellos.

One department of strings added to the wood-wind in unison produces a
sweet coherent quality, the wood-wind timbre still predominating; but
the addition of one wind instrument to all or part of the strings in
unison, only thickens the resonance of the latter, the wood-wind
timbre being lost in the process:

Vns I + Vns II + 1 Ob.,
or: Violas + 'Cellos + 1 Cl.
or: 'Cellos + D. basses + 1 Fag.

Muted strings do not combine so well with wood-wind, as the two tone
qualities remain distinct and separate. Uniting plucked strings and
percussion with instruments of sustained resonance results in the
following: wind instruments, wood and brass, strengthen and clarify
_pizzicato_ strings, harp, kettle-drums and percussion generally, the
latter lending a touch of relief to the tone of the wood-wind. Uniting
plucked strings and percussion with bowed instruments does not produce
such a satisfactory blend, both qualities being heard independently.
The combination of plucked strings with percussion alone, is
excellent; the two blend perfectly, and the consequent increase in
resonance yields an admirable effect.

The relationship which exists between string harmonics and the flute
or piccolo constitu