558 THE HUMAN BOLT. 



The end-lulls are spheroidal and about . 04 mm. (^-^ inch) 

 in diameter. Each consists of a core, with a connective- 

 tissue capsule, to which two or three nerve-fibres run; the- 

 axis cylinders penetrate the core. End-bulbs are found on 

 one or two regions of the skin, as that on the red part of 

 the lips, in the conjunctiva, and the mucous membrane 

 covering the soft palate, and the tongue. 



Touch, or the Pressure Sense. Through the skin w& 

 mvl Irindfi of fipup ^; touch proper, heat and cold, 



and pain; and we can with more or less accuracy localize 

 them on the surface ofthe i3odyT The interior of the 

 mouth possesses also these sensibilities. Through touch 

 proper we recognize pressure or traction exerted on the- 

 skin, and the force of the pressure; the softness or hard- 

 ness, roughness or smoothness, of the body producing it; 

 and the form of this, when not too large to be felt all over. 

 When to learn the form of an object we move the hand 

 -over it, muscular sensations are combined with proper 

 tactile, and such a combination of the two sensations 

 is frequent; moreover, we rarely touch anything without 

 at the same time getting temperature sensations; there- 

 fore pure tactile feelings are rare. From an evolution 

 point of view, touch is probably the first distinctly dif- 

 ferentiated sensation, and this primary position is still 

 largely holds in our mental life; we mainly think of the 

 things about us as objects which would give us certain tac- 

 tile sensations if we were in contact with them. Though 

 the eye tells us much quicker, and at a greater range, what 

 are the shapes of objects and whether they are smooth, 

 rough, and so on, our real conceptions of round and square 

 and rough bodies are derived through touch, and we trans- 

 late unconsciously the teachings of the eye into mental 

 terms of the tactile sense. A person who saw but had no 

 touch-sense would conceive solid objects very differently 

 from the rest of mankind. 



The delicacy of the tactile sense varies on different parts 

 of the skin; it is greatest on the forehead, temples, and 



