SIR CHARLES BELL ON THE ORGANS OF THE HUMAN VOICE. 307 
When the parts are displayed, so that we may look on the outside and poste- 
rior aspect of the great bag of the pharynx, we see how well it is adapted for the 
office which I shall assign to it in the formation of the human voice. It presents 
to our view a flat expanded web, of a fleshy or muscular texture, and it extends 
from the base of the skull to the extremities of the horns of the os hyoides and 
those of the thyroid cartilage, between which it is stretched and held out. 
Behind, its connexions are loose ; and as it forms a principal boundary of the 
bag of the pharynx, the great cavity of that bag is directly in front of it. If 
we trace the pharynx upwards from the closed extremity of the oesophagus, 
we perceive the glottis opening into it below ; whilst above, it is terminated by 
the posterior nostrils, and anteriorly by the mouth. 
Considering the passage for the voice as one irregular cavity, extending 
from the glottis to the lips and nostrils, we shall find it subject to great 
changes, and powerful in its influence on the voice. For although the breath 
is vocalized by the larynx, both the musical notes in singing and the vowels 
in speech, are affected by the form and dimensions of this cavity. 
Notwithstanding the ingenuity displayed in experiments on animals, to show 
that their cries proceed from the larynx, we have no authority to disregard the 
fact, that when a person who has divided the pharynx, and exposed the top of 
the windpipe, attempts to speak, no sound issues from the larynx. By great 
effort he may produce a noise ; but anything like the common effort of speak- 
ing is attended with no audible sounds. From this we must infer that the de- 
licate vibrations, necessary to articulate language, are influenced not merely 
by the action in the glottis, but by the condition of the walls of the pharynx ; 
the cavity into which the sound is thrown. 
In this part of the air-passage, we shall find an exact correspondence with 
the flute or pipe, in as far as it is lengthened during the grave sounds, and 
shortened in the acute. Even if it were proved that the note is made to rise 
and fall by the contractions of the glottis, the great apparatus employed to 
move the pharynx cannot be useless. We are countenanced in concluding, 
that as the tube of the organ is adjusted to the reed, so is the condition of the 
pharynx made to correspond with these contractions of the glottis. It is im- 
possible to see a singer running up the notes to the highest, without admitting 
that there must be a powerful influence produced through the alternate short- 
