g2 THE ROLLER CANARY 
separated by a tiny interval, so that one detects a 
succession of rolling syllables separated in a scarcely 
perceptible manner by a series of beats. As we have 
here the consonant “ g,” the beats are plainly discernible. 
Like all other tours, the quality (tonality) depends 
upon the purity and fullness of the ground tones, the 
softness of the consonants, and the knitting together of 
the syllables; in other words, the perfection of the run. 
Impure, faulty vowels sound nasal, loud consonants 
sound hard and pointed; a slack run leaves the tours 
loose, clattering, watery, which is also bad. To perform 
the tour well so that the bird produces a full tone, in 
spite of the numerous swift beats, he needs strong lung 
force. The finest form of this tour is Hollow Gluck Roll. 
Gluck Rolls are plentiful; when deep, they are fine 
passages, and therefore enrich the song. Already the 
deep position of this tour is commanding higher 
appreciation, for all deep tours should—nay, must—be 
fostered. 
