And elsewhere, by virtue of the roar of her waters, she uttered loud sounds. Thus assuming very many different aspects, when she fell from the sky, and reached the surface of the earth, she said to Bhagiratha, ‘O great king! show me the path that I shall have to take. O lord of the earth! for thy sake have I descended to the earth.’

In plain words: Ganga roared and took many forms as she fell. When she reached the earth, she asked Bhagiratha to show her the way to go, since she had come down for his sake.