288 IN STARRY REALMS. 



vided, then a vast volume of sound in this particular note 

 would be the result. In other words, this apparatus 

 would radiate, if I may use the expression, a note of one 

 particular wave length. But suppose that the sounding 

 boards were removed, and that the forest of strings was 

 placed between an auditor and an orchestra, all the music 

 from the orchestra would have to come through the strings 

 before the auditor could hear it ; the great majority of 

 notes would pass through and between the strings, no 

 doubt with some loss, but without any special interference. 

 All those notes, however, from whatever instrument in the 

 orchestra they might have come, which harmonized with a 

 particular note to which the strings resounded, would be 

 specially affected in their transit ; as the music breathed 

 past the wires they would commence to vibrate, because 

 certain notes were tuned with the vibration that the 

 strings were able to perform. The energy of the per- 

 formers in the orchestra, so far as it was expended on the 

 production of music of this particular note, would be em- 

 ployed in setting the forest of strings into a quiver, and 

 would thus lose its power to affect the ears of the auditors 

 at the end of the room. 



In this case the forest of strings would have really 

 acted as a sort of filter applied to the music diffused 

 from the orchestra; they would have stopped the pas- 

 sage of one particular note, while they would have per- 

 mitted notes of every other description to pass almost 

 unmolested. The forest of strings is in fact opaque to one 

 note, if I may use the expression, and transparent to every 

 other note. But now observe that when the sounding 

 boards are restored to the forest of strings, and when the 



