Page:Popular Science Monthly Volume 9.djvu/415

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VOICE IN MAN AND IN ANIMALS.
391

of the larynx be rent and torn; but it is destroyed by lesion of the nerves of the little muscles which alter the form of the glottis and stretch the vocal cords.

But alongside of these undisputed facts there were a number of undecided questions which stimulated to further research. Some investigators were continually meditating on methods of viewing the larynx in normal action. Toward the close of the last century mirrors were first employed for this purpose, but the earliest attempts were unsuccessful. For fifty years all efforts of this kind proved abortive, and the thought of examining the interior of a living larynx was coming to be regarded as an illusion. Suddenly, as by an inspiration, the solution of the problem occurred to the mind of Manuel Garcia. Ignorant of the labors of others who had endeavored to obtain a view of the vocal apparatus, Garcia conceived the idea of observing his own vocal organs in the act of singing. Taking a small mirror attached to the end of a long rod, he placed it beneath the uvula, and then, illuminating with a beam of sunlight another mirror which he held in his hand, he had a full view of his own larynx. Thus was discovered the true method of investigation. In 1855 Garcia communicated to the London Royal Society the result of his observations on the living larynx.[1]

When a new mode of research is discovered, the first investigators to take hold of it are those who have little or no prepossessions of their own. They perceive that, by varying the application of the process, notable results may be attained without much labor or ability. Garcia's process called forth on many sides much enthusiastic zeal. This was the case especially at Vienna, but the results fell short of the anticipations. The caprices of the sun's light and the defects of artificial light were such as to discourage the observers. In order to succeed, the means of illumination had to be improved at any cost. Garcia had used for a reflector a plane mirror; J. Czermak, Professor of Physiology at Pesth, finding his pattern in the instrument used for inspecting the eye, the ophthalmoscope, employed a concave mirror, which concentrates the light. The feasibility of studying man's vocal apparatus by means of the laryngoscope was now insured. Still, for a long time afterward, experimenters busied themselves with devising contrivances for increasing the intensity of the light by combinations of glass lenses.[2]

Czermak, who by long practice had acquired great skill in the manipulation of his own larynx, visited the principal cities of Germany, taking with him a good instrument. His demonstrations were

  1. "Observations on the Human Voice," "Proceedings of the Royal Society of London," vol. vii.
  2. The different kinds of instruments are described in Mandl's work, "Traité du Larynx;" also, in the article, "Laryngoscope," by Dr. Krishaber, in "Dictionnaire Encyclopédique des Sciences Médicales."