76 THE ROLLER CANARY 
Hollow Roll has the widest range of all the rolling 
tours, and, therefore, it varies considerably in pitch, as 
also in tone colour. For this reason it is regarded by 
many as the most beautiful of all the tours. These are 
matters of taste. It is very difficult to cultivate it deep, 
and there is always a danger of it going faulty, indefinite, 
nasal. Straight Hollow Roll, even when deep, is always 
sung on one note; a good falling roll sounds better, but 
the ideal is the deep, bent varicty, rising and falling in 
several keys. 
