A MUSICAL KEY. 



or else we must forever remain in ignorance of their 

 Individual character. We may value a half or a quarter 

 note according to our discretion, but once having de- 

 cided upon that value we must sustain it. 



If one does not possess that interesting and simple 

 little instrument called Maelzel's Metronome, the follow- 

 ing instructions will serve in the construction of an 

 excellent substitute. Attach a small weight to the end 

 of a common tape measure with half, quarter, and 

 eighth inches marked thereon ; a penknife suspended 

 crosswise (not lengthwise) will do. The following table 

 will then show the equation of inches and metronome 

 beats ; the last are indicated by the number per minute : 



60 = 39 inches 112 = llf inches 



66 = 31f " 116 = 10j " 



72 = 26f " 120 = 9^ " 



80 = 21f " 126 = S\ " 



88 = 18i <c 132= 7| " 



92 = 16* " 138 = 7 " 



96 = 15* " 144 = 6f " 



100 = 14f " 152 =6 " 



104 = 13f " 160 = 5| " 



108 = 12f " 168 = 4| " 



