PHYSIOLOGICAL PARADOXES. 



till the sound began again, and then detected 

 its origin in the fluttering of a moth at the top 

 of the window between the blind and the glass. 



The small sound in the same room had so 

 closely imitated a greater sound at a distance 

 as thoroughly to deceive two people who were 

 listening very carefully. 



It was not their ears that had misled them 

 and that eventually discovered the truth. The 

 ears had merely given information as to the 

 quality, intensity, and duration of the sound ; 

 and from these facts the mind had drawn in- 

 ferences, at first incorrectly, as to the direction 

 from which it came and as to its origin. 



Somewhat similar in the relation between 

 cause and effect was the circumstance which 

 furnishes the next example. 



Everyone who has spent much time in an 

 arable district, in autumn and winter, is familiar 

 with the loud droning noise made by the thresh- 

 ing-machine, and knows what a definite in- 

 dividual character it has. This sound was 

 distinctly heard in the stillness of the night, 

 about as loud as if it came from a farmstead 

 half a mile away, sometimes stopping and 

 starting again, sometimes louder or quieter, as 

 if the wind were changing its direction and 

 speed. 



The difficulty was that the neighbourhood 

 was a residential suburb, and the nearest farm- 

 stead was two miles away, with intervening 



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