STRINGED INSTRUMENTS 379 



given these notes, with the number of vibrations that 

 each makes. This series of tones, which is used for all 

 kinds of musical instruments the world over, is known as the 

 musical scale. Each higher tone in the next scale will 

 have twice the vibration rate of that of the corresponding 

 letter in the scale shown in the diagram, and each of the 



An instrument with many strings. Can you locate the strings which give the low tones ? 



next lower scale will have half the vibration rate of the 

 corresponding tone in the scale shown. There are on the 

 piano and organ keyboard black keys which have inter- 

 mediate rates of vibration. These are the so-called sharps 

 and flats, and without these notes modern music would 

 be impossible. 



Stringed instruments and how they make sound. - 

 We have already alluded to the fact that a note of low 

 pitch is caused by the vibration of a long string, while 



