198 FOOD AND FEEDING 



distinct regions or tracts, each of which has to perform its 

 own special office and function. The tip of the tongue is 

 concerned mainly with pungent and acrid tastes ; the 

 middle portion is sensitive chiefly to sweets and bitters ; 

 while the back or lower portion confines itself almost 

 entirely to the flavours of roast meats, butter, oils, and 

 other rich or fatty substances. There are very good reasons 

 for this subdivision of faculties in the tongue, the object 

 being, as it were, to make each piece of food undergo three 

 separate examinations (like ' smalls,' ' mods,' and ' greats ' 

 at Oxford), which must be successively passed before it is 

 admitted into full participation in the human economy. 

 The first examination, as we shall shortly see, gets rid at 

 once of substances which would be actively and imme- 

 diately destructive to the very tissues of the mouth and 

 body ; the second discriminates between poisonous and 

 chemically harmless food-stuffs ; and the third merely 

 decides the minor question whether the particular food is 

 likely to prove then and there wholesome or indigestible to 

 the particular person. The sense of taste proceeds, in fact, 

 upon the principle of gradual selection and elimination ; it 

 refuses first what is positively destructive, next what is 

 more remotely deleterious, and finally what is only undesi- 

 rable or over-luscious. 



When we want to assure ourselves, by means of taste, 

 about any unknown object say a lump of some white 

 stuff, which may be crystal, or glass, or alum, or borax, or 

 quartz, or rocksalt we put the tip of the tongue against it 

 gingerly. If it begins to burn us, we draw it away more 

 or less rapidly with an accompaniment in language strictly 

 dependent upon our personal habits and manners. The 

 test we thus occasionally apply, even in the civilised adult 

 state, to unknown bodies is one that is being applied every 

 day and all day long by children and savages. Unsophis- 



