"V: Having thoroughly assured myself, through such experiments as the one described above, that all sounds of the voice, whatever their intensity, were perceived by Vittorio, I proceeded to the attempt of making him compare these sounds. It was no longer a case of simply noting the sounds of the voice, but of perceiving the differences and of appreciating all these modifications and varieties of tone which go to make up the music of the word. Between this task and the preceding there stretched a prodigious difference, especially for a being whose development was dependent upon gradual effort, and who advanced toward civilisation only because I led thitherward so gently that he was unconscious of the progress. Facing the difficulty now presented, I had need to arm myself more strongly than ever with patience and gentleness, encouraged by the hope that once I had surmounted this obstacle all would have been done for the sense of hearing.
"We began with the comparison of the vowel sounds, and here, too, made use of the hand to assure ourselves as to the result of our experiments. Each one of the fingers was made the sign of one of the five vowels. Thus the thumb represented A and was to be raised whenever this vowel was pronounced; the index finger was the sign for E; the middle finger for I; and so on.
"VI: Not without fatigue, and not for a long time, was I able to give a distinct idea of the vowels. The first to be clearly distinguished was O, and then followed A. The three others presented much greater difficulty, and were for a long time confused. At last, however, the ear began to perceive distinctly, and, then, there returned in all their vivacity, those demonstrations of joy of which I have spoken. This continued until the pleasure taken in the lessons began to be boisterous, the sounds became confused, and the finger was raised indiscriminately. The outbursts of laughter became indeed so excessive that I lost patience! As soon as I placed the blindfold over his eyes the shouts of laughter began."
Itard, finding it impossible to continue his educational work, decided to do away with the blindfold, and, indeed, the shouts ceased, but now the child's attention was distracted by the slightest movement about him. The blindfold was necessary, but the boy had to be made to understand that he must not laugh so much and that he was having a lesson. The corrective means of Itard and their touching results are worth reporting here!