The Life of the Grasshopper 



From one end to the other there have been 

 cut across this bow about eighty triangular 

 teeth, which are very even and are of 

 some hard, durable material, dark-brown in 

 colour. 



The use of this mechanical gem is obvious. 

 If we take a dead Decticus and lift the flat 

 rim of the two wing-cases slightly in order 

 to place them in the position which they oc- 

 cupy when sounding, we see the bow fitting 

 its indentations to the terminal nervure 

 which I have called the friction-nervure; we 

 follow the line of teeth which, from end to 

 end of the row, never swerve from the 

 points to be set in motion; and, if the opera- 

 tion be done at all dexterously, the dead insect 

 sings, that is to say, strikes a few of its 

 clicking notes. 



The secret of the sounds produced by the 

 Decticus is out. The toothed bow of the left 

 wing-case is the motor; the friction-nervure 

 of the right wing-case is the point of con- 

 cussion; the stretched membrane of the 

 mirror is the resonator, to which vibration is 

 communicated by the shaking of the sur- 

 rounding frame. Our own music has many 

 vibrating membranes; but these are always 

 affected by direct percussion. Bolder than 



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