MUSICAL SOUNDS. 411 



Q. Why is the SOUND of a bell STOPPED by 

 TOUCHING the bell with our finger ? 



A. The weight of the finger stops 

 the vibrations of the bell ; and as soon as 

 the bell ceases to vibrate, it ceases to 

 make sound-waves in the air. 



Q. Why does a SPLIT BELL make a HOARSE 

 disagreeable sound ? 



A. The split of the bell causes a 

 double vibration; and as the sound- 

 waves clash and jar, they impede each 

 other's motion, and produce discordant 

 sounds. 



Q. Why does a FIDDLE-STRING give a musical 

 sound ? 



A. The bow drawn across the string 

 causes it to vibrate, and this vibration of 

 the string sets in motion the sound-waves 

 of the air, and produces musical notes. 



Q. Why does a DRUM sound ? 



A. The parchment head of the drum 

 vibrates from the blow of the drum-stick, 

 and sets in motion the sound-waves of 

 the air. 



Q. Why do MUSICAL GLASSES give sounds ? 



A. Because the glasses vibrate as 



Na2 



