74 THE ROLLER CANARY 
HOLLOW ROLL 
The hollow is founded on ii, 0, n, a, 6, e, a, and 
the roll is formed by the blending of the consonant r, 
therefore the syllable is rii, ro, ru, etc. The quality of 
the tour consists in the purity of the vowel, and the 
enunciation of the “r.’’ The finest ground tones are 
ui, o, u and a full round 6; these vowels, possessing of 
themselves a natural roundness, impart a wonderful 
fulness and charm to the song. 
Vowels a, e, 4 are of less value; a is somewhat weak 
and dull, e and 6 (the latter if not full and round) are 
coarse and heavy, and therefore weaken the tonality; 
a is bordering on the nasal, which is risky. 
If the “r’”’ is so evident as almost to smother the 
vowel sound, the tour becomes coarse, hard, and some- 
times scratchy; if it is moderate, combined with a deep 
“u,” or “o,” the tour runs on, gushing and purling. 
If the “‘r” is quite subdued, a soft k, h, and | being 
heard vibrating, the song becomes noble, charming, 
lulling (kullering), thus :—Klruhlruhlrohlroh. 
This kullering Hollow differs from simple Hollow 
Roll by reason of these soft, waving, hovering con- 
sonants, in deep, full tone, and the almost complete 
absence of the “r”’; it is evidently a development or 
expansion of Hollow Roll on “u” and “o.” 
Hollow Roll may, in general, be divided into four 
series, High, Middle, Deep, and Deepest. The high is 
of least merit, ground tone “i” ; the middle is fair, 
ground tone “iti”; the deep is good, ground tone “ti” 
and “6”; the deepest is the best, ground tone “o” 
ania hus"? 
When Hollow Roll is sung on one tone only, it is 
