OH. L.] NEEVE-ENDINGS. 691 



finger, the sight of an object to the eyes, &c. If the ulnar nerve 

 is stimulated by a knock on the elbow, the sensation is referred 

 to the fingers where the nerve is distributed ; if the stump of a 

 recently amputated leg be stimulated, the brain not having got 

 used to the new condition of things, refers the sensation to the 

 toes, which still seem to be present. 



Perception is a more complicated mental process ; it consists 

 in the grouping of sensations, and the imagining of the object 

 from which they arise, and which is called the percept. The 

 stnell, the taste, the colour, <fec., of an orange are all sensations ; 

 the grouping of these together constitutes the perception of an 

 orange. Each mental process leaves an impress on the mind ; 

 these impressions build up memory, or representative imagination ; 

 this may be reproductive, as in recalling a friend's face ; or 

 constructive, as in picturing the face of an historical person. 



During the whole operation, moreover, there must be attention ; 

 it is quite possible, for instance, in a dreamy person, that he may 

 look at a thing without seeing it, or be present at a lecture 

 without hearing it. 



The more complex intellectual operations consist in the forma- 

 tion of concepts, and reasoning the grouping and discrimination of 

 conceptions. Just as perception is built up of sensations, so 

 conception is built up of perceptions. Thus the orange of our 

 previous example is learnt to be one of similar substances called 

 fruits; fruits to be products of the vegetable, as distinguished 

 from the animal world, and so on. 



This is seen in the education of a child ; at first scattered 

 sensations only are perceived, and education consists in learning 

 what these sensations correspond to in the external world, and 

 how they may be classified. The other mental faculties are in 

 the same way built of simpler material ; the volitional operations 

 are at first simple responses to external conditions ; later on they 

 become more complex and representative, culminating in speech, 

 the most complicated movement of all. The emotions, too, are 

 at first simple, and merely exaggerated sensations ; the higher 

 ones are complex and representative. 



The nerve-endings that receive the impression from the external 

 world are of various kinds. They may be simply ramifying and 

 interlacing plexuses of nerve-fibrils, as in the cornea, parts of 

 the skin, and in the interior of the body ; this kind of nerve- 

 ending is chiefly associated with general sensibility, that vague 

 kind of sensation which cannot be put under any of the special 

 headings taste, sight, hearing, touch, and smell. The nerve- 

 endings of the nerves of special sense are usually end-organs of a 



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