ART. 9. HISTORY OF INVENTIONS HOUGH. 37 



struck, and the rubbed, according to the method in which their 

 strings are set into vibration. The most simple form of the open- 

 stringed instruments is a musical bow, which is both picked and 

 struck, and the most complex forms are the harp, the dulcimer, the 

 harpsichord, and the piano. The stopped-stringed is one whose 

 vibratory length may be shortened, thus raising the pitch and making- 

 it possible to produce on a single string one or more octaves, with all 

 the chromatic intervals. Of the stopped strings a simple form is the 

 African zeze, which has only two frets and often but one string, while 

 the most complex forms are the lutes, guitars, and violins. The few 

 examples here shown illustrate the progress of invention in perfect- 

 ing the open-stringed instruments. 



No. 1. Mahuga musical bow, from Mashonaland. Piece of cane with single 

 string of twisted cotton. Player holds it in his teeth to hear the 

 sound 167,518 



No. 2. Angola musical bow. Plain stick for bow ; string of twisted hemp cord ; 

 gourd resonator tied to grip of the bow ; open part of goura rests 

 against the stomach of the player; inclining the gourd gives two or 

 three tones (pi. 41) 167,517 



No. 3. Egyptian tambour or African lyre. Body boat-shaped, covered with raw- 

 hide ; neck a bent stick ; strings twisted fiber, reaching from median 

 line of the body to the overhanging neck ; tuning pegs transverse. 



No. 4. Finnish open-stringed psaltery (kantele) . Wire strings, of graduated 

 length stretched over wooden pegs tightened by wire keys 95,690 



No. 5. Kanoon, from Morocco. Body, a trapezoid ; gut strings of graduated 

 lengths tuned in groups of threes ; fixed bridge at oblique end ; raised 

 bridge resting on four squares of fish skin. Sound holes in sounding- 

 board. 



No. 6. Italian psalteria or dulcimer. Trapeze formed body. Series of strings 

 of graduated length, tuned in groups of four each. Fixed bridges at 

 each end of sounding board, and two diagonal rows resting on it. 



No. 7. Autoharp. Harmonics only are sounded. Inharmonic sounds dampened 

 by pressing down a series of spring bars 95,237 



SEEIES 3. — WIND INSTKTJMENTS OF MUSIC. 



Plate 42. 



Wind instruments are divided into several classes, namely, horns, 

 flutes, flageolets, flue-organ pipes, and reed instruments. Horns are 

 musical tubes in which the lips of the player set the column of air 

 within the tube into vibration. The longer the tube of a horn the 

 lower the note produced, the greater the number of harmonics that 

 can be obtained by varying the pressure and velocity of sound pass- 

 ing through the tube. There are two methods of changing the pitch 

 of the fundamental note of a horn, and consequently its harmonics; 

 first, by adding to the length of the windway, either by a sliding 

 joint, as in the trombone, or by adding fixed lengths of the windway, 

 as in cornets and other similar instruments; second, by placing lat- 



