_ue_, _oeu_ (French sound in coeur), _au_, _oi_. Thus, for
the above eight vowels, instead of 1, 2, 3, 4, 5, 6, 7, 8, the order 3,
1, 2, 7, 4, 6, 5, 8, so that only _i_ and _ue_ keep their place. But
other children give a varying order, and these differences in the order
of succession of vowels as well as of consonants will certainly not be
referred to the "influence of heredity." Two factors of quite another
sort are, on the contrary, to be taken into account here in the case of
every normal child without exception, apart from the unavoidable errors
in every assigned order growing out of incomplete observation. In the
earliest period and when the babbling monologues begin, the cavity of
the mouth takes on an infinitely manifold variety of forms--the lips,
tongue, lower jaw, larynx, are moved, and in a greater variety of ways
than ever afterward. At the same time there is expiration, often loud
expiration, and thus originates entirely at random sometimes one sound,
sometimes another. The child _hears_ sounds and tones new to him, hears
his own voice, takes pleasure in it, and delights in making sounds, as
he does in moving his limbs in the bath. It is natural that he should
find more pleasure in some sounds, in others less. The first are more
frequently made by him on account of the motor memories that are
associated with the acoustic memories, and an observer does not hear
the others at all if he observes the child only from time to time. In
fact, however, almost all simple sounds, even the most difficult, are
formed in purity before they are used in speaking in the first eight
months--most frequently those that give the child pleasure, that satisfy
his desires, or lessen his discomfort. It is not to be forgotten that
even the _ae_, which requires effort on account of the drawing back and
spreading out of the tongue, diminishes discomfort. The fretful babe
feels better when he cries _u-ae_ than when he keeps silent. The second
factor is determined by the surroundings of the child. Those sounds
which the child distinctly hears he will be able to imitate correctly
sooner than he will other sounds: but he will be in condition to hear
most correctly, first of all, the sounds that are most frequent, just
because these most frequently excite the auditory nerve and its tract in
the brain; secondly, among these sounds that are acoustically most
sharply defined, viz., first the vowels, then the resonants (m, n, ng);
last, the co