BOUND. 103 



into heat" Theories like these are very easily advanced, but 

 rather difficult to prove. We would like to ask the professor 

 how long under the most favourable circumstances for accumula- 

 tion, it would take fifty ordinary church organs to heat St. 

 Paul's Cathedral 1 



The experiments which are made m every Scientific Institu- 

 tion, to illustrate the various phases of sound and vibration are 

 both numerous and beautiful, but we fail to see that sound is 

 vibration of the atoms of the atmosphere only, and that it 

 cannot exist independently of such motion. 



For instance, if we sound a bugle on a warm summer's day, 

 and again on a clear frosty day, it is heard with twice the 

 distinctness, and at twice the distance, on the latter occasion, 

 although the vibrations are theoretically the same. 



Again metal is the best conductor of sound, and a long piece 

 of iron, from its mineral character, will yield more sound when 

 struck, than a similar piece of wood, although in theory, the 

 vibration is necessarily the same. 



Suppose a bar of iron, twenty feet long, by twelve inches 

 square, lay on the ground, and we strike it with a tiny hammer, 

 sound would result, although it is impossible that the bar could 

 vibrate. Again if the bar were suspended and struck with the 

 same force, we would have more sound, and yet there would be 

 no vibration, thus showing that the position of atoms has a 

 great deal to do with sound. If the material composing a bell 

 were cast in any .>thiT shape, it would not yield nearly so much 

 sound as before the < -lia: 



While we admit that in many instances, vibration causes 

 sound, and particular vibrations cause particular notes, yet we 

 could no more say vibration of itself was sound, than that a 



