“Soota said, ‘The Naagaas (snakes) after consultation arrived at the conclusion that they should do their mother’s (Kadru’s) command, for if she failed in obtaining her desire she might withdraw her affection and burn them all. If, on the other hand, she were graciously inclined, she might free them from her curse. They said, ‘We will certainly make the horse’s (Uchchaihshravas’) tail black.’ It is said that they (snakes) then went and became hairs in the horse’s (Uchchaihshravas’) tail.
“Now the two co-wives (of Maharishi Kashyapa – namely Kadru and Vinata) had laid the bet. O best of Brahmanas (Rishi Shaunaka), having laid the bet the two sisters Kadru and Vinata, the daughters of (Prajaapati) Daksha, proceeded in great delight along the sky to see the other side of the Ocean. On their way they saw the Ocean, that vessel of waters, incapable of being easily disturbed, mightily agitated all of a sudden by the wind, and roaring tremendously; abounding with fishes capable of swallowing the whale and full of makaras; containing also creatures of diverse forms counted by thousands; frightful from the presence of horrible monsters, inaccessible, deep, and terrible, the mine of all kinds of gems, the home of Varuna, the wonderful habitations of the Naagaas (snakes), the lord of rivers, the abode of the subterranean fire; the residence of the Asuras and of many dreadful creatures; the reservoir of water, not subject to decay, aromatic, and wonderful, the great source of the Amrita of Devas; immeasurable and unthinkable, containing waters that are holy, filled to the brim by many thousands of great rivers, dancing as it were in waves.
“Such was the Ocean, full of rolling waves, vast as the expanse of the sky, deep, of body lighted with the flames of subterranean fire, and roaring, which the sisters (Kadru and Vinata) quickly passed over.’”
SRIMAD MAHABHARATA – AADI PARVA – AASTIKA (UPA) PARVA – PART 22 – KADRU AND VINATA CROSS THE OCEAN