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GENERAL SCIENCE 



act as a resonant box which, by automatically changing its form and 

 size, causes different qualities of tone. 



FIG. 320. One of the largest pipe organs in the world. Why is it necessary 

 to have long and short pipes? What kind of tones do you think the long 

 pipes would produce? 



Piano Player. Piano player action depends upon the atmos- 

 pheric pressure. The hammers are made to strike the strings of the 



