FUSED SENSATIONS. 273 



side; namely, that there may be a decided current of water 

 over the nerve endings ; for it is found that if the human nos- 

 trils be filled with rose-water no odor is perceived. 



In what is called Aristotle's experiment, the experimenter 

 crosses the first and second finger, and feels an object with 

 the fingers thus crossed and eyes shut. If a marble be rolled 

 about by the two fingers thus crossed, it seems to be two. 

 Here we use Judgment with the sensation. Ordinarily we 

 could not feel one simple solid object with the outside of the 

 first and the inside of the second finger at the same time. 

 This illustrates how we are constantly using our judgment in 

 interpreting our sensations. We see few things as they are 

 in themselves. We see nearly everything in the light of past 

 experiences. 



We have noted the lingering effects of sensations, how 

 sights and sounds linger and are fused one with the other, 

 so we get continuous light from a series of flashes if they 

 follow each other in sufficiently rapid succession, and con- 

 tinuous sound from a series of sounds that would be heard 

 separately if they are more than about a sixteenth of a second 

 apart. So with touch, if the finger be held against the teeth 

 of a revolving wheel, if the wheel revolve slowly, the touch 

 of each tooth may be felt, but when it whirls more rapidly 

 the sensation becomes that of continuous pressure. And it 

 is of vastly greater significance that the cells whose activity 

 gives consciousness that a more permanent effect still is 

 produced ; so that we may recall, in the act called Imagina- 

 tion, the sensation that was originally caused by the action of 

 some external object, through the nerve-ending and the nerve, 

 upon the nerve-cells in the brain. Experience and experiment 

 both go to show that probably nothing is wholly forgotten. 

 Whatever acts upon a cell of nervous matter makes its mark. 

 It may become dim, but it is never completely obliterated. 



