154 



THE APPLICATIONS OF PHYSICAL FORCES. [BOOK n. 



which they are tuned. They are seldom or never used in orchestras ; 

 but the guitar and mandoline are frequently used by singers in 

 southern countries. 1 



The harp, the antiquity of which is proved beyond doubt, is a 

 stringed instrument put into vibration by the fingers. Its form differs 



FIG. 105. The Loiitar. 



FIG. 10(> Theorbo, or arch-lute. 



entirely from the violin, guitar or other instruments of these types. 

 Although comparatively little used in the present day, it deserves a 

 special description. The plucked string is almost the symbol of a 

 pure and pleasing sound, owing to the great predominance given to 



1 " The origin of the guitar has never been determined. We have this instrument 

 from the Spaniards, among whom it was really introduced by the Moors. The 

 general opinion in Spain is that it is as ancient as the harp." DIDEROT ET 

 D'ALEMBERT'S Encyclopaedia.- -[Surely the Moors took it from the Egyptian "tam- 

 poura " ghitterncithera]. 



