THE SENSE OF TOUCH. 



279 



papillae. In these papillae are certain important nerve 

 endings. There are several kinds of nerve endings in the 

 skin and underneath it that receive the impressions which, 

 carried to the brain, give us sensations of touch (and allied 

 sensations to be considered soon). Pressure on the skin 

 affects these nerve endings, and 

 starts impulses that pass along the 

 sensor fibers to some nerve center, 

 probably in the spinal cord, spinal 

 bulb, or brain. 



Touch Corpuscles. These 

 "touch corpuscles" are not re- 

 garded as essential for producing 

 the sensation of touch, but some 

 nerve endings in the skin do seem 

 necessary ; for if a nerve fiber be 

 touched, not at the end, but some- 

 where along its course, we get, not 



a sensation of touch, but a sensation of pain. Except in 

 the mouth and nose, we get little, if any, sense of touch 

 from any organ but the skin. The lining of the digestive 

 tube and the internal organs generally are devoid of this 

 sense. 



The Sense of Touch. Of the special senses the most 

 general is that of touch. Seeing and hearing, taste and 

 smell, belong to very limited parts of the outside of the 

 body, but we have the power of feeling all over the surface 

 of the body. 



Touch the most General of the Special Senses. 



Not only is the sense of touch the most general in being 

 distributed over the whole of the body, but it is the most 

 widely distributed sense throughout the animal kingdom 



Nerve 



Fig. 85. Papilla of Skin with 

 Touch Corpuscle. 



