NATURAL THEOLOGY. 189 



nice, is managed in this manner. The gullet (the 

 passage for food) opens into the mouth like the 

 cone or upper part of a funnel, the capacity of 

 which forms indeed the bottom of the mouth. 

 Into the side of this funnel, at the part which lies 

 the lowest, enters the windpipe by a chink or 

 slit, with a lid or flap, hke a little tongue, accu- 

 rately fitted to the orifice. The solids or liquids 

 which we swallow pass over this lid or flap as they 

 descend by the funnel into the gullet. Both the 

 weight of the food and the action of the muscles 

 concerned in swallowing contribute to keep the 

 lid close down upon the aperture whilst any thing 

 is passing ; whereas, by means of its natural car- 

 tilaginous spring, it raises itself a little as soon as 

 the food is passed, thereby allowing a free inlet 

 and outlet for the respiration of air by the lungs. 

 Such is its structure ; and we may here remark 

 the almost complete success of the expedient, viz., 

 how seldom it fails of its purpose compared with 

 the number of instances in which it fulfils it. Re- 

 flect hovr frequently we swallow, how constantly. 

 we breathe. In a city feast, for example, what 

 deglutition, what anhelation ! yet does this httle 

 cartilage, the epiglottis, so effectually interpose 

 its office, so securely guard the entrance of the 

 windpipe, that whilst morsel after morsel, draught 

 after draught, are coursing one another over it^ 

 an accident of a crumb or a drop slipping into 

 this passage, (which, nevertheless, must be opened 

 for the breath every second of time,) excites in the 



