Aitareyabrahmana 3.27

3.27

What she seized with her right foot became the morning pressing.
That the gāyatrī made her own abode;
therefore do they consider it the most thriving of all the pressings.
He becomes foremost and principal,
he attains superiority, who knows thus. Then what she seized with her left foot
became the midday pressing.
That slipped down; having slipped down, it did not equal the former pressing.
Those gods desired to find out [how to remedy it];
in it they placed the triṣṭubh among the metres and Indra among the deities.
By that, it became equal in virility to the former pressing. Through both pressings
equal in virility and equal in kinship does he prosper who knows thus. Then
what she seized with her beak became the third pressing.
Flying along, she sucked its juice; with its juice sucked out, it did not equal the former two pressings.
Those gods desired to find out [how to remedy it]; they saw it in cattle.
Therefore, in that they pour on the milk-mixture, and proceed with the animal offering and melted butter,
by that it became equal in virility to the former two pressings.
Through all the pressings equal in virility and equal in kinship does he prosper who knows thus.