BRAIN AND MIND 



with the organs and tissues lying without the brain. 

 These essential cells are so infinitesimal in size that 

 many millions of them lie imbedded in each cubic 

 centimeter of the brain substance. We need not here 

 attempt to surmise how they perform the work that is 

 laid out for them, but we may tell pretty definitely what 

 that work is. The fibres from the cells run out to the 

 periphery of the body, and there become a part of all 

 of the tissues that are in contact with the outer world. 

 For convenience we may think of these fibres as tele- 

 graph wires that convey messages from the outer world 

 to the brain-cell. If any part of our body comes in 

 contact with an exterior object, we at once feel that the 

 surface of that object is soft or hard, as the case may be; 

 that it is cold or warm, rough or smooth, and the like. 

 We seem to learn all this instantaneously, but in point 

 of fact we do not know it until the impressions received 

 at the finger-tip, for example, have been transmitted 

 to the brain, and there interpreted by the brain-cells. 

 In the process of this interpretation, the mind appears. 

 The same thing is true of all impressions that we 

 receive through the organs of special sense. The eye 

 does not see, the ear does not hear, the tongue does 

 not taste, the nose does not smell; but each of these 

 organs receives impressions from different kinds of 

 forces of the external world, and transmits them to 

 the brain; and it is the tiny brain-cell that develops 

 the complex sensations in question. The superficial 

 organ of sense is like the transmitter of a telephone. 

 The nerve fibril is the transmitting wire. The brain- 

 cell is the internal transmitter, back of which stands 



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