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 with 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 that part of the tongue.
"Wine is a mocker, strong drink is raging; and whosoever is deceived thereby is not wise."—Proverbs xx.
1000. Why, when we draw the tongue in, do we recognise the sweetness of the sugar?