Valmiki

“ They were, perhaps, at first the morning star and evening star. They are said to be the children of the sun and the nymph As'viní, who is one of the lunar asterisms personified. In the popular mythology they are regarded as the physicians of the Gods. ”

“ O'er thee fatigue shall ne'er prevail,
Nor age or change thy limbs assail.
Thee powers of darkness ne'er shall smite
ln tranquil sleep or wild delight.
No one is there in all the land
Thine equal for the vigorous hand. ”