162 SYSTEMS OF TREATING STAMMERING "It has always been observed that stammering ceases as though by magic when the person afflicted sings or recites words to musical or poetic measure. But no one has sought to explain this phenomenon; though an explanation is of the highest importance for the treatment of an infirmity that occurs so often, and which one usually regards as, with few exceptions, beyond the aid of curative art. "Two causes, one the result of the other, are accountable for the stammerer's fluency in singing. The first is that, since he is compelled to accord to his utterance a musical and poetic rhythm, the movements of the organs concerned in phonation must needs occur with greater accuracy and regularity. The second is that, since the stammerer must constantly have the idea of measure, this accessory idea offsets the relative prepon- derance of the main idea giving rise to the conversation; and, further, that this accessory thought modifies the cerebral ex- citation, whence it follows that the neural irradiation pro- ceeds more slowly and in a more orderly manner, thus falling more into harmony with the contraction of the speech-muscles. Rhythm is capable of regulating not only the irregular move- ments of the speech-organs; but it exerts a salutary influence on all the other organs of the human body. The following observations, selected from a considerable number, demon- strate this fact: "M. — is the son of a prefect and a nephew of an old minis- ter of the interior; was a student at the polytechnical school, but is now in military service. With this gentleman the pecu- liarities of speech and the convulsive movements that affected him, disappeared as though by magic during the time that he was practising the various exercises of the vocal organs that we prescribed for his impediment. The same thing occurred when he played the piano or heard another person playing a musical instrument. In 1833 we treated a young woman, — Mile.