VOICE IN MAN AND IN ANIMALS. 387 



of its activity. 1 At present he is engaged in studying the phenomena 

 of voice in the larger animals. As for birds, it is to he hoped that 

 soon we shall understand the organic peculiarities in virtue of which 

 they are able to talk or to sing. Doubtless before long we shall dis- 

 cover the relations subsisting between life-conditions, physical powers, 

 and psychological faculties. 



In all those communities which have attained a high degree of in- 

 tellectual culture, the explanation of natural phenomena has ever more 

 or less engaged the attention of the best minds. Among the ancients 

 we observe a manful effort to discover the secret of the human organ- 

 ization. The origin of speech and of song was unquestionably a sub- 

 ject of profound inquiry for them. Galen, the last and the most famous 

 of the ancient physicians, wrote a description of the larynx, and this 

 description is the work of a master who recognizes the high impor- 

 tance of the work he is engaged in. Since the time of the Renaissance 

 anatomists have been studying the minutest details, and physiologists 

 experimenting. Thus everything was ready for new discoveries, so 

 soon as it should be possible to place before the eye the performance 

 of the instrument used by the singer. It would be difficult, without 

 some knowledge of the vocal apparatus, to understand how the sounds 

 are produced, and hence we will briefly describe those portions of the 

 respiratory organs in which the voice is formed. 



The trachea, which is the passage for air between the mouth and 

 the lungs, ascends from the chest to the middle region of the neck; 

 it is made up of cartilaginous rings. At its lower extremity it branches 

 out into two tubes, which are divided and subdivided into numerous 

 ramifications : these are the bronchi, which terminate in the lung-cells. 

 At the upper extremity of the trachea is the larynx, appearing like 

 an angular box, and crowning the trachea like the capital on a column. 

 Cartilages connected by ligaments give considerable strength to the 

 walls of the larynx. Internally these walls have a lining of mucous 

 membrane, which forms folds known as the vocal cords, or better, 

 lips. Under the action of special muscles these folds separate from 

 one another, are elongated or shortened, or become tense, and hence 

 the differences of sound. The cartilages are four in number: two on 

 the anterior surface of the box and two on the sides. In advanced 

 age these cartilaginous plates ossify ; the suppleness of the larynx is 

 then greatly diminished, and the voice loses the power of modulation 

 which it possessed in the period of youth. One of the cartilages, 

 which has the form of a ring, is much higher behind than in front. 

 This ring, being firmly fixed upon the first ring of the trachea, serves 

 to support the various parts which constitute the larynx. The largest 

 of these parts shields, as it were, the front of the vocal apparatus: it 

 consists of a plate of cartilage bent into a V-shape, with the point of 



1 " Traite du Larynx et du Pharynx," 1872 ; " Hygiene de la Voix parlee et chantee," 

 1876. 



