148 ALIMENTARY ORGANS. 



which run round the passage, and which, by drawing 

 the throat together ahove the food, as the food pro- 

 ceeds, force it along in its descent. In the horse, ox, 

 &c. which have to swallow in a direction contrary 

 to the weight of the food, there is a double set of 

 these forcing muscles, which cross one another around 

 the throat, and act with a much greater power. 



J5. I have often wondered that these animals 

 should be able to raise their drink and food with 

 such perfect ease into their long necks. The most 

 familiar circumstances, I perceive, furnish occasion 

 to admit the skill and kindness of that Creator, who 

 giveth to the beast his food, and whose tender mer- 

 cies are over all his works. 



T. But this is only a small part of the contrivance 

 necessary in furnishing us with a throat. 



A.. The lungs open into the throat. The open- 

 ing is called the glottis, and is situated in the upper 

 part of the throat, just below the palate. It is ne- 

 cessary for breathing ; but still a dangerous opening 

 we perceive, from a place where a crumb of bread 

 might be fatal, into the great channel through which 

 all our food has to descend. But the foresight was 

 equal to the peril. It is wonderful to notice how the 

 danger has been avoided. The opening is covered 

 with a small valve, or clapper, opening upwards, an- 

 atomist call it the epiglottis, which plays over the 

 entrance, and which the food closes before it in its 

 descent. Nor is this the whole of this beautiful 

 contrivance. The glottis itself is so constructed, 

 that it draws together, whenever any particle of liqui d 



