II, is changed thus:

[Music: (as printed)

en aucun temps n'eut choisi mieux.

(should be sung)

en aucun temps n'eut choisi mieux.]

* * * * *

INTENSITY

In musical terminology every gradation of volume in sound, from the
faintest to the loudest, enters into the category of Intensity. One of
the accepted rules of the _arte del bel canto_ was, that every
sustained tone should be coloured by some graduation of intensity.
Thus the ability to augment and diminish the volume of tone was so
highly esteemed--indeed, so essential--that singers spent much time in
acquiring the _messa di voce_, that is, the steadily graduated
emission of tone from the softest degree to the loudest and again to
the softest: _p_ [crescendo symbol] _f_ [decrescendo symbol] _p_. This
exercise invariably formed a part of each day's study, and was
practised on several vowels throughout the scale, except the extreme
tones, save in rare instances. It was, in fact, indispensable that the
singer should be able to colour every tone in three forms of graduated
intensity: Soft to loud _p_ [crescendo symbol] _f_; loud to soft _f_
[decrescendo symbol] _p_; and soft to loud and soft again _p_
[crescendo symbol] _f_ [decrescendo symbol] _p_.

This command of intensity, therefore, is invaluable. But it is even
more effective when the artist has the power to combine the various
gradations of Intensity with different shades of Colour; in other
words, when he can sing a tone _crescendo_ and _diminuendo_ in the
clear and sombre timbres.

The passage, already cited, from Alceste's great air in Gluck's opera
_Alceste_, furnishes an admirable illustration of the dramatic emotion
created by a sudden contrast of Intensity as well as Colour. In the
invocation "Ye ministers that dwell in night!" the clear timbre is
used with gradually increasing volume until at the phrase (sung
_adagio_) "Ministers of death!" the timbre changes abruptly to a
sombre quality with sinister effect, which effect is augmented by
being sung _pp_.

[Music: Gluck (Alceste: Act I)

Divinites du Styx!
Divinites du Styx!
Ministres de la mort!]

A still more striking example of the impressive effect produced by
sudden contrasts of intensity is offered in the magnificent air "Total
Eclipse," from _Samson_ (Handel). In it, a judicious use of
tone-colour, accent, and variations of tempo, all combine to elucidate
in the highest possible degree the idea of