The prototype is a medieval folk song published in a number of collections: Gamar Katipa "National Songbook" (Tiflis, 1856), M. Miansaryants "Armenian Harp", K. Kostanyants, "New Collection" (B Volume, Tiflis, 1892) and others.
Probably, Toumanian used the "New Collection" version. He chose the first 15 of the 32 lines, turned the Medieval Armenian of the folk song into a literary language, changed one line and a few words, left out the often-repeated sound "Hay!, gave the modern meaning to the word "manuk" used in medieval songs to mean "young"*. This fundamentally changed the nature of the poem.
This folk song was also developed by the 17th century poet Yeremya Chelepi Kyomurchyan.
*In modern Armenian "manuk" means baby child.
GURGLING water down a cloudy mount
Runs by the village with a happy sound.
Out runs a little boy, his skin brown ,
Face and hands need a wash down.
Washing with the cool water he chose,
The boy turns and like this, he goes:
