THE SPECIAL SENSES. 127 



the papillae start up, giving the coat of the tongue a velvety 

 appearance. 



In order to taste any substance it must be in solution. 

 We cannot taste the sweetness of sugar until some part of 

 it melts on the tongue. Anything that will not dissolve is 

 tasteless. The different tastes seem to be limited to certain 

 parts of the tongue. For instance, salty and bitter sub- 

 stances are best tasted at the back part, while the tip takes 

 notice oi; sweet substances and the edges best appreciate 

 acids. We have natural tastes and we have acquired tastes. 

 In his original state, man is guided almost solely by the 

 natural sense of taste in selecting his food. Amongst civi- 

 lized people there are many acquired tastes. While the 

 sense of taste is intended to distinguish between what is 

 suitable and what is not suitable to enter the stomach, we 

 often violate this sense and take what is not good because we 

 have acquired the taste. No one will say, not even the toper, 

 that liquor is agreeable to the taste, even from the very start- 

 ing of the habit. The hot, fiery liquor is never agreeable, 

 but it is forced upon the delicate taste bulbs, and their 

 judgment is ignored, until this sense becomes depraved. It is 

 possible, also, to train the taste to tolerate, and even to like, 

 certain articles of food which at first are not palatable. 



The appearance of the tongue varies in different persons. 

 In some it has a smooth, soft, even surface. In others it is 

 mapped out in sections by deep lines, which intersect each 

 other. In a healthy state of the system it is reddish in color, 

 but is readily affected by disorders of the stomach, and covers 

 over with a whitish or brownish coating. 



In some animals the surface of the tongue is very rough. 

 The papillae are long, and stand out firm and stiff. The cat, 

 for instance, has a rough tongue, while some beasts of prey 

 can strip the flesh from the bones of their victims with the 

 tongue alone. 



