The tenth month is marked by the increasing distinctness of the syllables in the monologues, which are more varied, louder, and more prolonged when the child is left to himself than when any one tries to entertain him. Of new syllables are to be noted ndäĕ, bāë-bāë, ba ell, arrö.
From the forty-second week on, especially the syllables mä and pappa, tatta, appapa, babba, tätä, pa, are frequently uttered, and the uvular rrrr, rrra, are repeated unweariedly. The attempts to make the child repeat syllables pronounced to him, even such syllables as he has before spoken of his own accord, all fail. In place of tatta he says, in the most favorable instance, tä or ata; but even here there is progress, for in the previous month even these hints at imitating or even responding to sound were almost entirely lacking.
In the eleventh month some syllables emphatically pronounced to the child were for the first time correctly repeated. I said "ada" several times, and the attentive child, after some ineffectual movements of the lips, repeated correctly ada, which he had for that matter often said of his own accord long before. But this single repetition was so decided that I was convinced that the sound-imitation was intentional. It was the first unquestionable sound-imitation. It took place on the three hundred and twenty-ninth day. The same day when I said "mamma," the response was nanna. In general, it often happens, when something is said for imitation, and the child observes attentively my lips, that evident attempts are made at imitation; but for the most part something different makes its appearance, or else a silent movement of the lips.
In the forty-fifth week everything said to the child, in case it received his attention, was responded to with movements of lips and tongue, which gave the impression of being made at random and of serving rather for diversion.
Further, at this period the child begins during his long monologues to whisper. He produces sounds in abundance, varying in force, pitch, and timbre, as if he were speaking an unknown tongue; and some single syllables may gradually be more easily distinguished, although the corresponding positions of the mouth pass into one another, sometimes quite gradually, sometimes rapidly. The following special cases I was able to establish by means of numerous observations:
In crying rrra, there is a vibration on both sides of the edges of the tongue, which is bent to a half-cylinder with the ridge upward. In this way the child produces three kinds of r-sounds—the labial, the uvular, and this bilateral-lingual.
New syllables of this period are ta-he͡e, dann-tee, a͡a-ne͡e, ngä, tai, bä, dall, at-tall, kamm, akkee, praï-jer, tra, ā-he͡e. Among them tra and pra are noteworthy as the first combination of t and p with r. The surprising combinations attall and akkee and praijer, which made their appearance singly without any occasion that could be noticed, like others, are probably the first attempts to reproduce the child's own name (Axel Preyer) from memory. Of earlier sounds, syllables, and combinations of these, the following are especially frequent: Mammam, apapa, örrö, papa, tata, tatta, na͡a, rrra, pata, mmm, nă, ā, ä, a͡u, anna, attapa, dadada, ja, ja-ja, eja, jaë. The last syllables are distinguished by the distinct e, which is now more frequent.
All the pains taken to represent a babbling monologue perfectly by letters were fruitless, because these distinct and oft-repeated syllables alternated with indistinct loud and soft ones. Still, on the whole, of the consonants the most frequent at this period are b, p, t, d, m, n, and the new r; l, g, k, not rare. Of vowels the a has a decided preponderance. Both u and o are rare; i very rare. Yet a vowel is not repeated, either by itself or in a syllable, more than five times in succession without an interval. Commonly it is twice or three times. I have also noticed that the mechanical repetition of the same syllable, e. g., papapa, occurs far more often than the alternation of a distinctly spoken syllable with, another distinctly spoken one, like pata. In the mean time it is certain that the child during his various movements of lips and tongue, along with contraction and expansion of the opening of the mouth, readily starts with surprise when he notices such a change of acoustic effect. It seems as if he were himself taking pleasure in practicing regularly all sorts of symmetrical and asymmetrical positions of the mouth, sometimes in silence, sometimes with loud voice, then again with soft voice. In the combinations of syllables, moreover, palpable accentuation somewhat like this, appápapa atátata, is by no means frequent. The surprisingly often repeated dadada has generally no accent.
With regard to the question whether in this period, especially important for the development of the apparatus of speech, any articulate utterance of sound stands in firm association with an idea, I have observed the child under the most varied circumstances possible without disturbing him; but I have ascertained only one such case with certainty. The atta, hödda, hatta, hataï, showed itself to be associated with the perception that something disappeared, for it was uttered when some one left the room, when the light was extinguished, and the like; also, to be sure, sometimes when such remarkable changes were not discoverable. Thus, the eleventh month ends without any other indubitable firm association of articulation and idea.
In the next four weeks, up to the end of the first year of life, there was no progress in this respect to record; but, from this time on, an eager desire—e. g., for a biscuit seen, but out of reach—was regularly announced by ä-na, ä-nananana, uttered loudly and with an expression of indescribable longing.