uch commoner than the second,
and is indeed the one kind of _crescendo_ that is possible in piano
playing; but the second variety can be secured in the case of an organ
with swell box, the human voice, and in both string and wind
orchestral instruments. Since some of the most beautiful musical
effects may be produced by the use of this second type of crescendo,
it should be employed very much more than it is in choral and
orchestral music. The English conductor Coward takes the ground that
the swell (a combination of _crescendo_ and _diminuendo_) is the most
powerful choral effect in existence.[17]

[Footnote 17: Coward, _Choral Technique and Interpretation_, p. 112.]

When the composer wishes to build up a really tremendous climax and
sweep all before him by the intensity of the emotional excitement
generated, he frequently indicates an increase in the amount of tone,
coupled with a very gradual acceleration in tempo, all proceeding by
slow degrees, and perhaps accompanied by a rise from a low pitch
register to higher ones. If on the other hand, he wants to let down in
emotional intensity, he does the opposite of all these things. The
combination of _crescendo_ and _ritardando_ is also tremendously
effective.

In order to bring together in fairly comprehensive array the terms
that are ordinarily used by the composer to indicate various
expressional effects, a table of the most frequently encountered
dynamic expressions is here included.

_Pianississimo_ (_ppp_) }
_pianissimo possibile_ } (as softly as possible)

_pianissimo_ (_pp_) (superlative of _piano_--very softly)

_piano_ (_p_) (softly)

_piu piano_ (more softly)

_il piu piano_ (most softly)

_piano assai_ (very softly)

_mezzo-piano_ (_mp_) (moderately softly)

_forte_ (_f_) (loudly)

_fortissimo_ (_ff_) (superlative of _forte_--very loudly)

_fortississimo_ (_fff_) (as loudly as possible)

_piu forte_ (more loudly)

_il piu forte_ (most loudly)

_il piu forte possibile_ (as loudly as possible)

_mezzo forte_ (_mf_) (moderately loudly)

_forte-piano_ (_fp_) (loudly followed immediately by softly)

_forzando_ (_z_) } (These words and signs indicate that
_sforzando_ (_sf_ or _sfz_) } a single tone or chord is to be
_forzato_ (_fz_) } accented, the amount of stress
_sforzato_ (_sf_ or _sfz_) } depending upon the chara