PROCESS OF SWALLOWING. 211 



When the morsel of food is ready to be swallowed, the 

 tongue pushes it back into the pharynx ; the soft palate is 

 raised to shut off the passage into the nasal cavity ; the larynx 

 is pulled upward and forward ; the epiglottis is pulled down' 

 over the glottis, or opening of the windpipe ; and the base of 

 the tongue extends back over the epiglottis ; thus the air pas- 

 sages, above and below, are shut off, and the food passes over 

 the epiglottis into the gullet. The muscles of the pharynx 



Eustachian Tube 



Soft Palate, Raised 

 Food 



Epiglottis, Down 

 Gullet, Open 



Glottis, Closed 



Fig. 59b. Diagram, Showing the Positions of the Organs of the Mouth and 

 Throat During Swallowing, 



also do their part in pushing the food along. As soon as the 

 food has passed over the epiglottis, the epiglottis rises to its 

 upright position, and the soft palate drops back to its place, 

 leaving the air passages again open. As we are swallowing 

 only a small part of the time, the passageway naturally stands 

 open to the air ; and when we swallow, the parts are, by mus- 

 cular effort, temporarily adjusted for this work. It is to be 



