_Their importance._--Sound, we have said, is the language of man in the
sensitive state. We call inflections the modifications which affect the
voice in rendering the emotions of the senses. The tones of the voice
must vary with the sensations, each of which should have its note. Of
what use to man would be a phonetic apparatus always rendering the same
sound? Delivery is a sort of music whose excellence consists in a
variety of tones which rise or fall according to the things they have to
express. Beautiful but uniform voices resemble fine bells whose tone is
sweet and clear, full and agreeable, but which are, after all, bells,
signifying nothing, devoid of harmony and consequently without variety.
To employ always the same action and the same tone of voice, is like
giving the same remedy for all diseases. "_Ennui_ was born one day from
monotony," says the fable.

Man has received from God the privilege of revealing the inmost
affections of his being through the thousand inflections of his voice.
Man's least impressions are conveyed by signs which reveal harmony, and
which are not the products of chance. A sovereign wisdom governs these
signs.

With the infant in its cradle the signs of sensibility are broken cries.
Their acuteness, their ascending form, indicate the weakness, and
physical sorrow of man. When the child recognizes the tender cares of
its mother, its voice becomes less shrill and broken; its tones have a
less acute range, and are more poised and even. The larynx, which is
very impressionable and the thermometer of the sensitive life, becomes
modified, and produces sounds and inflections in perfect unison with the
sentiments they convey.