TASTE, SMELL, AND HEARING. 



303 



Olfactory Nerves J 



Branches of 

 Fifth Nerve 



Turbinated Bones 



The Sense of Smell. "The sense of odor gives us 

 information as to the quality of food and drink, and more 

 especially as to the quality of the air we breathe. Hence 

 we find the organ placed at the opening of the respiratory 

 passages, and in close proximity to the organs devoted to 

 taste. Taste is at the gateway of the alimentary canal, 

 just as smell is the sentinel of the respiratory tract; and 

 just as taste, when combined with smell to give the sen- 

 sation we call 

 flavor, influ- 

 ences the di- 

 gestive pro- 

 cess, and is 

 influenced by 

 it, so smell 

 influences the 

 respiratory process. The 

 presence of odors influ- 

 ences both the amplitude 

 and the number of the 

 respiratory movements. 

 Thus the smell of winter- 

 green notably increases the 



respiratory work, next comes ylang-ylang, and last rose- 

 mary. The breathing of a fine odor is therefore not only 

 a pleasure, but it increases the amplitude of the respira- 

 tory movements. Just as taste and flavor influence nutri- 

 tion by affecting the digestive process, and as the sight of 

 agreeable or beautiful objects, and the hearing of melo- 

 dious and harmonious sounds react on the body and help 

 physiological well-being, so the odors of the country, or 

 even those of the perfumer, play a beneficent role in the 

 economy of life." M'KENDRICK and SNODGRASS. 



Fig. 92. Nerves of the Outer Wall of the 

 Nasal Cavity. 



