286 DETAILED SYNTHESIS. 



able, apartments of a proper temperature, neither too 

 cool nor too warm, baths for the skin, brisk rubbing to 

 circulate the blood freely through it, and clothing ap- 

 propriate for all seasons and all kinds of weather ; that 

 we should walk and ride and exercise in various ways in 

 the open air, where the skin can receive agreeable influ- 

 ences and produce numerous and lively sensations. 



Remark. The skin and the care it should receive will again be a 

 proper subject for instruction when the eliminating organs are consid- 

 ered. 



The Mouth as an Organ of Sense. 



716. THE MOUTH is PRIMARILY an organ for prepar- 

 ing the food for the digestory action of the stomach, but 

 that duty is changed into a pleasure by the addition of 

 the nerves of taste. 



717. NERVES OF TOUCH EXTEND from every part of 

 the mouth to the nervous centres, in the same manner 

 as they do from the skin, generally ; they are called 

 nerves of common sensation. 



718. THE NERVES or TASTE COMMENCE in the papil- 

 lae, on the sides and tip of the tongue, in those about its 

 roots, from some of tkose in the sides of the back part 

 of the mouth, and from some of those of the soft palate. 



719. THE NERVES OF TASTE OR TOUCH MAY BE PAR- 

 ALYZED without the other being affected, or either may 

 be in either half only. 



720. SOME SUBSTANCES do not have the power of 

 affecting the nerves of taste, and are called tasteless; some 

 produce taste in some persons and not in others ; some 

 produce slight effects on some and strong taste in others. 



721. Remark. Whether substances produce the same identical 

 kind of sensation in all persons who taste them is uncertain ; it is not 

 probable they do. 



722. THAT SUBSTANCES MAY BE TASTED they must be 



716. What is ? 717. From what part of the mouth do ? 71 8. Where do ? 

 719. How may ? 720. What effect on taste of - ? 722. What necessary ? 



