The Special Senses 245 



378. Modifications of the Sense of Taste. Taste is modi- 

 fied to a great extent by habit, education, and many other 

 circumstances. Articles of food that are unpleasant in 

 early life often become agreeable in later years. The most 

 savory dishes may excite disgust, while the simplest articles 

 may have a delicious flavor to one long deprived of them. 

 The taste for certain articles is certainly acquired. This 

 is often true of raw tomatoes and olives. 



The organs of taste and smell may be regarded as neces- 

 sary accessories of the general apparatus of nutrition and are, 

 therefore, more or less essential to the maintenance of 

 animal life. While taste and smell are generally main- 

 tained until the close of life, sight and hearing are often 

 impaired by time and may be altogether destroyed in 

 extreme old age. 



Experiment no. Light helps the sense of taste. Shut the eyes, 

 and palatable foods taste insipid. Pinch the nose," close the eyes, 

 and see how palatable one-half of a teaspoonful of cod-liver oil 

 becomes. 



Experiment in. Close the nostrils, shut the eyes, and attempt to 

 distinguish by taste alone between a slice of an apple and one of a 

 potato. 



379. Effect of Tobacco and Alcohol upon Taste. Alcoholic 

 liquors and tobacco tend to impair the delicate sensibility 

 of the tender papillae of the tongue. The keen appreciation 

 of fine flavors is destroyed. The once clear and enjoyable 

 taste for plainly cooked foods is diminished. Highly spiced 

 and seasoned articles of diet are craved, indulgence in 

 which usually results in various forms of indigestion. 



380. Smell. The sense of smell is lodged in the delicate 

 membrane which lines the nasal cavities. Man, in common 

 with all air-breathing animals, has two nasal cavities. They 

 communicate with the outer air by two nostrils opening in 



