76 VISION. 



nerves in which your consciousness resides, or would 

 even know that you had such things unless those to 

 whom the interior of the body is known by dissec- 

 tion had told you. 



It is very startling, and to the unscientific very 

 confusing. I do not care at the present moment to 

 press the inquiry further. All the length which I 

 wish to lead you just yet is to appreciate that even 

 in touch, which is the simplest of our senses, there 

 is no immediate contact of the mind with external 

 objects. At most, you are only aware of the posi- 

 tions in which your various sensations are felt : you 

 are not conscious of the things which cause those 

 sensations. 



Let us turn now from common sensation to vision. 

 Vision is the most subtile and most complex of all 

 the senses. It is produced by the vibrations of 

 light, vibrations vastly more minute than those of 

 sound ; and even sonorous vibrations are for the 

 most part incapable of affecting the sense of touch ; 

 although, no doubt, if one stands near a piano with a 

 tense parchment in his hand, he will feel the notes 

 producing vibrations in his fingers. Further, we 

 not only appreciate light and darkness by vision, 

 but the exact relative position of very numerous 

 spots of light, with their various degrees of intensity 

 and their differences of colour, all at the one time. 



