en _o_
is the first tone with _e_ as the second, the other sounds in turn
ending the group. Next _ah_ is the second sound, then _eh_, _i_, _oo_
and _ah_ might be used as the second vowel-element, making thirty-five
combinations with _o_ as the initial sound of each group. The same
number of combinations can be made with _ah_ as the first tone, and so
on with each of the seven vowel-elements.

Sixteen of these groups, changed from time to time as may be desired,
can be written upon the blackboard and sung by the class in the way set
forth, the teacher meanwhile keeping time for and directing the class.

It may be observed in this connection, that, as the voice ascends in
pitch, there is a tendency to blend the various vowel-sounds into one
sound. As the tones grow higher the sound-waves are focused at higher
points upon the hard-palate, the sounding-board of the resonance
cavities, and more difficulty is experienced in moulding these
sound-waves into the forms characteristic of the different
vowel-elements. As the parts concerned in tone-formation gain in
flexibility, the result appears in the ease with which the alterations
in shape of the resonance tube are made at higher pitches.

Fads and devices which divert attention from the subject and retard
rather than accelerate the progress of pupils are common enough in
schools, but the following simple illustrations of different vowel-forms
may be found useful:

[Illustration:
{mouth shapes}
[-e] [)i] eh
{mouth shapes}
ah aw o oo]

The base line represents the floor or base of the mouth-cavity, and the
arch, the height and width of the mouth for each sound; the depth is not
indicated. The width of the mouth from side to side is represented as
greatest in _[-e]_, _[)i]_ and _eh_, while the height is greater in
_ah_ and _aw_, _o_ is pictured as nearly round, and _oo_ the same,
only small.

It is not contended that these diagrams picture the actual form assumed
by the resonance cavities very accurately. The various positions which
the tongue and the soft-palate assume are not shown at all, nor,
perhaps, is it necessary; for if the pupil is taught to drop the lower
jaw to the right position for each sound, and to keep the tongue prone
in the mouth, a mental picture of each tone will be formed, and the
thought will regulate the action. When the pupil can think the sound
desired, the conditions for its formation will be met by the vocal
organs. The usefu