COSMIC PHILOSOPHY 



sity answering to the wave's maximum ampli- 

 tude when it has risen to its greatest height ; and, 

 thirdly, a period of minimum intensity, answer- 

 ing to the wave's minimum amplitude when it 

 has sunk nearly to the level again ; while be- 

 tween these minima and the maximum there 

 are many varying degrees of loudness. In other 

 words, every elementary sound is at first faint, 

 then gradually becomes loud, then grows fainter, 

 till it disappears. Now note what happens when 

 elementary sounds are made to succeed each 

 other. If the succession be irregular, there is 

 a mere chaos of noises — a case with which we 

 need not here deal. But if the succession be 

 regular, and steadily increase in rapidity, there 

 follows a remarkable series of results. As long 

 as the waves or pulses answering to the elemen- 

 tary sounds succeed each other slowly, the sounds 

 are distinguishable from each other as raps or 

 puffs, according to the instrument employed, 

 and each has its maximum and its two minima 

 of intensity. But when the waves begin to strike 

 the ear at the rate of about sixteen in a sec- 

 ond, the consciousness of separate raps or puffs 

 becomes evanescent, and there arises the con- 

 sciousness of a continuous tone of very low 

 pitch. That the consciousness of the separate 

 sounds has not quite ceased, and that the con- 

 tinuousness of the tone which they compose 

 is not complete, are shown by the fact that the 

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