THE BEJLSON WHY. 241 



" Can that which is unsavoury he eaten without salt ? or is there any taste in 

 the white of an egg ?" JOB T r. 



towards them, and thereby receives the readiest intimation of tho?e 

 bodies floating in the air which may be pleasurable to the sense, or 

 offensive to the smell, and injurious to life. 



995. Why is the nose placed over and near the moutTi f 



Because, as one of the chief duties ot that organ is to exercise a 

 watchfulness over the purity of the substances we eat and drink, 

 it is placed in that position which enables it to discharge that duty 

 with the greatest readiness. 



CHAPTER L. 



990. Why do we taste ? 



Because the tongue is endowed with gustatory nerves, having the 

 function of taste as their special sense, just as the optic, the 

 auditory, and the olfactory nerves, have their special duties in the 

 eyes, ears, and nose. 



997. Why do some substances taste sweet, others sour, 

 others salt, fyc. ? 



It is believed that the impressions of taste arise from the various 

 forms of the atoms of matter presented to the nerves of the tongue. 



998. Why do we taste substances most satisfactorily after 

 they have remained a little while in the mouth ? 



Because the nerves of taste are most abundantly distributed to 

 the under surface of the tongue ; and when solid substances have 

 been in the mouth a little while, they impregnate the saliva of the 

 mouth with their particles and come in contact in a fluid solution 

 tcith the gustatory nerves. 



999. Why if we put a nub of sugar to the tip of the tongue 

 has it no taste ? 



Because the gustatory nerves are not distributed to thai part of 

 th( tongue. 



