STRINGED INSTRUMENTS. 517 



The most ingenious mode of causing musical vibration is the 

 Bow, which is too familiar to need a detailed description. 

 Suffice it to say that it really is a modified bow, the place of 

 the string being supplied by a flat band of horsehair, which 

 is drawn over the string, and so causes it to vibrate. In order 

 to enable the bow to grip the string, it is rubbed with resin 

 almost -as often as a billiard-player chalks his cue. 



Some skill is required even in producing a sound by the 

 bow. It looks as if any one could do it, but a novice, if he 

 extorts any sound at all, never rises above a squeak. When 

 I took my first violin lessons, nearly thirty years ago, I was 

 so horrified at the discordant sounds elicited from the instru- 

 ment, that I retired to the topmost garret of the house in 

 order not to hurt any one's feelings except my own. 



JEW'S HAHP. 



ON the left hand of the illustration is seen a well-known 

 example of the imitation of Nature by Art. This is the 

 common Cricket, whose loud shrill call is more familiar than 

 agreeable. 



Some years ago, while engaged on my " Insects at Home," 

 I gave much time to the examination of the structures by 

 which such a sound can be produced. On the under side of 

 the wing-covers, or " elytra," as they are scientifically termed, 

 are notched ridges, which, when examined with a moderate 

 power of the microscope, have something of this appearance 

 _. The friction of these notches produces the musical 

 sound, which, as the reader will see, is exactly analogous to the 

 friction of the bow upon the string. 



