196 



SCIENTIFIC RECREATIONS. 



musical note is thus produced in the same way as the air causes a note in 

 an organ pipe. Faraday attributed the sound to rapid vibration caused by 

 successive explosions of the burning gas. The Gas Harmonicon has been 

 made on this principle. The air, being heated in the glass tube, ascends, 

 and the flame is thus permitted to come up more forcibly in the tube ; so 

 violent agitation results when the air tries to get into the opening above. 

 The size of the flame and its position in the tube will give a certain note 

 which will be the same note as the air would emit if in a pipe, for the 

 vibrations give the sound. 



Sir Charles Wheatstone has shown by experiment how sound can be 

 transmitted by placing a rod on a musical-box, and carrying the r.od through 

 the ceiling. When a guitar or violin was placed upon the rod, the sounds 

 of the musical-box were distinctly heard in the upper room. A Phantom 

 Band can be made by connecting certain instruments with others being 

 played on under the stage. Every one will then appear to play by itselil 



